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Caswell AM, Tripp TR, Kontro H, Edgett BA, Wiley JP, Lun V, MacInnis MJ. The influence of sex, hemoglobin mass, and skeletal muscle characteristics on cycling critical power. J Appl Physiol (1985) 2024; 137:10-22. [PMID: 38779761 DOI: 10.1152/japplphysiol.00120.2024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2024] [Revised: 04/29/2024] [Accepted: 05/15/2024] [Indexed: 05/25/2024] Open
Abstract
Critical power (CP) represents an important threshold for exercise performance and fatiguability. We sought to determine the extent to which sex, hemoglobin mass (Hbmass), and skeletal muscle characteristics influence CP. Before CP determination (i.e., 3-5 constant work rate trials to task failure), Hbmass and skeletal muscle oxidative capacity (τ) were measured and vastus lateralis (VL) muscle biopsy samples were collected from 12 females and 12 males matched for aerobic fitness relative to fat-free mass (FFM) [means (SD); V̇o2max: 59.2 (7.7) vs. 59.5 (7.1) mL·kg·FFM-1·min-1, respectively]. Males had a significantly greater CP than females in absolute units [225 (28) vs. 170 (43) W; P = 0.001] but not relative to body mass [3.0 (0.6) vs. 2.7 (0.6) W·kg·BM-1; P = 0.267] or FFM [3.6 (0.7) vs. 3.7 (0.8) W·kg·FFM-1; P = 0.622]. Males had significantly greater W' (P ≤ 0.030) and greater Hbmass (P ≤ 0.016) than females, regardless of the normalization approach; however, there were no differences in mitochondrial protein content (P = 0.375), τ (P = 0.603), or MHC I proportionality (P = 0.574) between males and females. Whether it was expressed in absolute or relative units, CP was positively correlated with Hbmass (0.444 ≤ r ≤ 0.695; P < 0.05), mitochondrial protein content (0.413 ≤ r ≤ 0.708; P < 0.05), and MHC I proportionality (0.506 ≤ r ≤ 0.585; P < 0.05), and negatively correlated with τ when expressed in relative units only (-0.588 ≤ r ≤ -0.527; P < 0.05). Overall, CP was independent of sex, but variability in CP was related to Hbmass and skeletal muscle characteristics. The extent to which manipulations in these physiological parameters influence CP warrants further investigation to better understand the factors underpinning CP.NEW & NOTEWORTHY In males and females matched for aerobic fitness [maximal oxygen uptake normalized to fat-free mass (FFM)], absolute critical power (CP) was greater in males, but relative CP (per kilogram body mass or FFM) was similar between sexes. CP correlated with hemoglobin mass, mitochondrial protein content, myosin heavy chain type I proportion, and skeletal muscle oxidative capacity. These findings demonstrate the importance of matching sexes for aerobic fitness, but further experiments are needed to determine causality.
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Affiliation(s)
- Allison M Caswell
- Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
| | - Thomas R Tripp
- Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
| | - Hilkka Kontro
- Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
| | - Brittany A Edgett
- Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
| | - J Preston Wiley
- Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
- Sport Medicine Centre, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
| | - Victor Lun
- Sport Medicine Centre, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
| | - Martin J MacInnis
- Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
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Peden DL, Rogers R, Mitchell EA, Taylor SM, Bailey SJ, Ferguson RA. Skeletal muscle mitochondrial correlates of critical power and W' in healthy active individuals. Exp Physiol 2024. [PMID: 38593224 DOI: 10.1113/ep091835] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2024] [Accepted: 03/25/2024] [Indexed: 04/11/2024]
Abstract
The asymptote (critical power; CP) and curvature constant (W') of the hyperbolic power-duration relationship can predict performance within the severe-intensity exercise domain. However, the extent to which these parameters relate to skeletal muscle mitochondrial content and respiratory function is not known. Fifteen males (peak O2 uptake, 52.2 ± 8.7 mL kg-1 min-1; peak work rate, 366 ± 40 W; and gas exchange threshold, 162 ± 41 W) performed three to five constant-load tests to task failure for the determination of CP (246 ± 44 W) and W' (18.6 ± 4.1 kJ). Skeletal muscle biopsies were obtained from the vastus lateralis to determine citrate synthase (CS) activity, as a marker of mitochondrial content, and the ADP-stimulated respiration (P) and maximal electron transfer (E) through mitochondrial complexes (C) I-IV. The CP was positively correlated with CS activity (absolute CP, r = 0.881, P < 0.001; relative CP, r = 0.751, P = 0.001). The W' was not correlated with CS activity (P > 0.05). Relative CP was positively correlated with mass-corrected CI + IIE (r = 0.659, P = 0.038), with absolute CP being inversely correlated with CS activity-corrected CIVE (r = -0.701, P = 0.024). Relative W' was positively correlated with CS activity-corrected CI + IIP (r = 0.713, P = 0.021) and the phosphorylation control ratio (r = 0.661, P = 0.038). There were no further correlations between CP or W' and mitochondrial respiratory variables. These findings support the assertion that skeletal muscle mitochondrial oxidative capacity is positively associated with CP and that this relationship is strongly determined by mitochondrial content.
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Affiliation(s)
- Donald L Peden
- School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, UK
| | - Robert Rogers
- School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, UK
| | - Emma A Mitchell
- School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, UK
| | - Suzanne M Taylor
- School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, UK
| | - Stephen J Bailey
- School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, UK
| | - Richard A Ferguson
- School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, UK
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D'Alleva M, Giovanelli N, Graniero F, Billat VL, Fiori F, Marinoni M, Parpinel M, Lazzer S. Effects of 24-week Polarized Training vs. Threshold Training in Obese Male Adults. Int J Sports Med 2024; 45:282-291. [PMID: 37402392 DOI: 10.1055/a-2123-0851] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/06/2023]
Abstract
The combination of high volume of moderate-intensity continuous training with a low volume of high-intensity interval training improved body composition and physical capacities in individuals with obesity. However, polarized training (POL) has never been used in adult men with obesity. Thus, the purpose of this study was to investigate changes in body composition and physical capacities induced by a 24-week POL or threshold (THR) program in obese male adults. Twenty male patients (mean age 39.8±6.3 yrs; mean body mass index [BMI] 31.6±2.7 kg∙m-2) participated in this study (n: 10 POL, n: 10 THR). After 24-week, body mass (BM) and fat mass (FM) decreased by -3.20±3.10 kg (P<0.05) and -3.80±2.80 kg (P<0.05), respectively, similarly in both groups. Maximal oxygen uptake ( ̇VO2max) and ̇VO2 at respiratory compensation point (RCP) increased in the POL group (+8.5±12.2 and+9.0±17.0%, P<0.05) and in the THR group (+4.24±8.64 and+4.0±6.70%, P<0.05), as well ̇VO2 at gas exchange threshold (GET) increased similarly in both groups (+12.8±12.0%, P<0.05). POL and THR were equally effective in improving body composition and physical capacities in obese subjects. Future studies are needed to determine whether adherence to the training program can be improved by adding a running competition compared with a group without competition at the end of the training program.
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Affiliation(s)
- Mattia D'Alleva
- Deparment of Medicine, University of Udine, Udine, Italy
- School of Sport Sciences, University of Udine, Udine, Italy
| | - Nicola Giovanelli
- Deparment of Medicine, University of Udine, Udine, Italy
- School of Sport Sciences, University of Udine, Udine, Italy
| | - Francesco Graniero
- Physical Exercise Prescription Center, Azienda sanitaria universitaria Friuli Centrale, Gemona del Friuli, Italy
| | | | - Federica Fiori
- Deparment of Medicine, University of Udine, Udine, Italy
| | | | - Maria Parpinel
- Deparment of Medicine, University of Udine, Udine, Italy
| | - Stefano Lazzer
- Deparment of Medicine, University of Udine, Udine, Italy
- School of Sport Sciences, University of Udine, Udine, Italy
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Dos Santos DFC, Wanner SP, de Paula RF, Zanetti GO, de Oliveira DCX, Orsatti FL, Teixeira-Coelho F. Acute alcohol ingestion decreases the work done above the end-test power during a 3-min all-out cycling exercise. Alcohol Alcohol 2024; 59:agae017. [PMID: 38529709 DOI: 10.1093/alcalc/agae017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Revised: 02/19/2024] [Accepted: 03/10/2024] [Indexed: 03/27/2024] Open
Abstract
INTRODUCTION Alcohol ingestion influences metabolism during a subsequent exercise session, as evidenced by increased blood lactate concentration during fixed-intensity exercise. Therefore, augmented blood concentrations of alcohol may interfere with the anaerobic metabolism during high-intensity, short-duration exercise bout, thereby leading to impaired athletic performance. OBJECTIVE This study investigated whether the acute ingestion of alcohol as ethanol modulates performance parameters derived from the power-duration relationship in a 3-min all-out cycling test that allows for identifying the power output related to heavy and severe exercise intensities. METHODS Twenty-four recreationally active cyclists (16 men and 8 women) ingested a beverage containing either 0.4 g ethanol.kg-1 body mass (EtOH) or a placebo (PLA) solution. Thirty minutes following ingestion, they completed a 3-min all-out test to measure power output and determine the end-test power (EP) and the work done above EP (WEP). RESULTS Alcohol ingestion decreased WEP by 16% (EtOH: 5.6 ± 2.5 kJ vs. PLA: 6.7 ± 2.4 kJ; P = .003) but did not change EP (EtOH: 211 ± 44 W vs. PLA: 212 ± 44 W; P = .671). The alcohol-mediated effect in WEP was not influenced when controlling for participants' sex or accuracy in identifying the beverage ingested. CONCLUSION Our data indicate that alcohol ingestion impaired the anaerobic work capacity, as evidenced by the reduction in WEP during the 3-min all-out test. Moreover, the ability to exercise at an intensity above the heavy domain may be decreased after ingestion of a moderate alcohol dose.
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Affiliation(s)
| | - Samuel Penna Wanner
- Exercise Physiology Laboratory, Department of Physical Education, School of Physical Education, Physiotherapy and Occupational Therapy, Universidade Federal de Minas Gerais, Belo Horizonte, 31270-901, MG, Brazil
| | - Rodolfo Ferreira de Paula
- Department of Sport Sciences, Health Science Institute, Universidade Federal do Triângulo Mineiro, Uberaba, 38025-440, MG, Brazil
| | - Gustavo Oliveira Zanetti
- Exercise Physiology Laboratory, Department of Physical Education, School of Physical Education, Physiotherapy and Occupational Therapy, Universidade Federal de Minas Gerais, Belo Horizonte, 31270-901, MG, Brazil
| | | | - Fabio Lera Orsatti
- Department of Sport Sciences, Health Science Institute, Universidade Federal do Triângulo Mineiro, Uberaba, 38025-440, MG, Brazil
| | - Francisco Teixeira-Coelho
- Department of Sport Sciences, Health Science Institute, Universidade Federal do Triângulo Mineiro, Uberaba, 38025-440, MG, Brazil
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McIntosh MC, Anglin DA, Robinson AT, Beck DT, Roberts MD. Making the case for resistance training in improving vascular function and skeletal muscle capillarization. Front Physiol 2024; 15:1338507. [PMID: 38405119 PMCID: PMC10884331 DOI: 10.3389/fphys.2024.1338507] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2023] [Accepted: 01/26/2024] [Indexed: 02/27/2024] Open
Abstract
Through decades of empirical data, it has become evident that resistance training (RT) can improve strength/power and skeletal muscle hypertrophy. Yet, until recently, vascular outcomes have historically been underemphasized in RT studies, which is underscored by several exercise-related reviews supporting the benefits of endurance training on vascular measures. Several lines of evidence suggest large artery diameter and blood flow velocity increase after a single bout of resistance exercise, and these events are mediated by vasoactive substances released from endothelial cells and myofibers (e.g., nitric oxide). Weeks to months of RT can also improve basal limb blood flow and arterial diameter while lowering blood pressure. Although several older investigations suggested RT reduces skeletal muscle capillary density, this is likely due to most of these studies being cross-sectional in nature. Critically, newer evidence from longitudinal studies contradicts these findings, and a growing body of mechanistic rodent and human data suggest skeletal muscle capillarity is related to mechanical overload-induced skeletal muscle hypertrophy. In this review, we will discuss methods used by our laboratories and others to assess large artery size/function and skeletal muscle capillary characteristics. Next, we will discuss data by our groups and others examining large artery and capillary responses to a single bout of resistance exercise and chronic RT paradigms. Finally, we will discuss RT-induced mechanisms associated with acute and chronic vascular outcomes.
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Affiliation(s)
| | - Derick A. Anglin
- School of Kinesiology, Auburn University, Auburn, AL, United States
| | | | - Darren T. Beck
- School of Kinesiology, Auburn University, Auburn, AL, United States
- Edward Via College of Osteopathic Medicine–Auburn Campus, Auburn, AL, United States
| | - Michael D. Roberts
- School of Kinesiology, Auburn University, Auburn, AL, United States
- Edward Via College of Osteopathic Medicine–Auburn Campus, Auburn, AL, United States
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Drake J, Finke A, Ferguson R. All models are wrong, but some are more wrong than others. Eur J Appl Physiol 2024; 124:671-673. [PMID: 37987922 DOI: 10.1007/s00421-023-05363-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2023] [Accepted: 10/28/2023] [Indexed: 11/22/2023]
Affiliation(s)
- Jonah Drake
- Department of Mathematical Sciences, School of Science, Loughborough University, Loughborough, UK.
| | - Axel Finke
- Department of Mathematical Sciences, School of Science, Loughborough University, Loughborough, UK
| | - Richard Ferguson
- School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, UK
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Tripp TR, McDougall RM, Frankish BP, Wiley JP, Lun V, MacInnis MJ. Contraction intensity affects NIRS-derived skeletal muscle oxidative capacity but not its relationships to mitochondrial protein content or aerobic fitness. J Appl Physiol (1985) 2024; 136:298-312. [PMID: 38059287 DOI: 10.1152/japplphysiol.00342.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Revised: 11/16/2023] [Accepted: 12/02/2023] [Indexed: 12/08/2023] Open
Abstract
To further refine the near-infrared spectroscopy (NIRS)-derived measure of skeletal muscle oxidative capacity in humans, we sought to determine whether the exercise stimulus intensity affected the τ value and/or influenced the magnitude of correlations with in vitro measures of mitochondrial content and in vivo indices of exercise performance. Males (n = 12) and females (n = 12), matched for maximal aerobic fitness per fat-free mass, completed NIRS-derived skeletal muscle oxidative capacity tests for the vastus lateralis following repeated contractions at 40% (τ40) and 100% (τ100) of maximum voluntary contraction, underwent a skeletal muscle biopsy of the same muscle, and performed multiple intermittent isometric knee extension tests to task failure to establish critical torque (CT). The value of τ100 (34.4 ± 7.0 s) was greater than τ40 (24.2 ± 6.9 s, P < 0.001), but the values were correlated (r = 0.688; P < 0.001). The values of τ40 (r = -0.692, P < 0.001) and τ100 (r = -0.488, P = 0.016) correlated with myosin heavy chain I percentage and several markers of mitochondrial content, including COX II protein content in whole muscle (τ40: r = -0.547, P = 0.006; τ100: r = -0.466, P = 0.022), type I pooled fibers (τ40: r = -0.547, P = 0.006; τ100: r = -0.547, P = 0.006), and type II pooled fibers (τ40: r = -0.516, P = 0.009; τ100: r = -0.635, P = 0.001). The value of τ40 (r = -0.702, P < 0.001), but not τ100 (r = -0.378, P = 0.083) correlated with critical torque (CT); however, neither value correlated with W' (τ40: r = 0.071, P = 0.753; τ100: r = 0.054, P = 0.812). Overall, the NIRS method of assessing skeletal muscle oxidative capacity is sensitive to the intensity of skeletal muscle contraction but maintains relationships to whole body fitness, isolated limb critical intensity, and mitochondrial content regardless of intensity.NEW & NOTEWORTHY Skeletal muscle oxidative capacity measured using near-infrared spectroscopy (NIRS) was lower following high-intensity compared with low-intensity isometric knee extension contractions. At both intensities, skeletal muscle oxidative capacity was correlated with protein markers of mitochondrial content (in whole muscle and pooled type I and type II muscle fibers) and critical torque. These findings highlight the importance of standardizing contraction intensity while using the NIRS method with isometric contractions and further demonstrate its validity.
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Affiliation(s)
- Thomas R Tripp
- Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
| | | | | | - J Preston Wiley
- Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
- Faculty of Kinesiology, University of Calgary Sport Medicine Centre, Calgary, Alberta, Canada
| | - Victor Lun
- Faculty of Kinesiology, University of Calgary Sport Medicine Centre, Calgary, Alberta, Canada
| | - Martin J MacInnis
- Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
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Hellsten Y, Gliemann L. Peripheral limitations for performance: Muscle capillarization. Scand J Med Sci Sports 2024; 34:e14442. [PMID: 37770233 DOI: 10.1111/sms.14442] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2023] [Revised: 06/20/2023] [Accepted: 06/22/2023] [Indexed: 10/03/2023]
Abstract
Sufficient delivery of oxygen and metabolic substrates, together with removal of waste products, are key elements of muscle performance. Capillaries are the primary site for this exchange in skeletal muscle and the degree of muscle capillarization affects diffusion conditions by influencing mean transit time, capillary surface area and diffusion distance. Muscle capillarization may thus represent a limiting factor for performance. Exercise training increases the number of capillaries per muscle fiber by about 10%-20% within a few weeks in untrained subjects, whereas capillary growth progresses more slowly in well-trained endurance athletes. Studies show that capillaries are tortuous, situated along and across the length of the fibers with an arrangement related to muscle fascicles. Although direct data is lacking, it is possible that years of training not only enhances capillary density but also optimizes the positioning of capillaries, to further improve the diffusion conditions. Muscle capillarization has been shown to increase oxygen extraction during exercise in humans, but direct evidence for a causal link between increased muscle capillarization and performance is scarce. This review covers current knowledge on the implications of muscle capillarization for oxygen and glucose uptake as well as performance. A brief overview of the process of capillary growth and of physical factors, inherent to exercise, which promote angiogenesis, provides the foundation for a discussion on how different training modalities may influence muscle capillary growth. Finally, we identify three areas for future research on the role of capillarization for exercise performance.
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Affiliation(s)
- Ylva Hellsten
- The August Krogh Section for Human Physiology, Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark
| | - Lasse Gliemann
- The August Krogh Section for Human Physiology, Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark
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McDougall RM, Tripp TR, Frankish BP, Doyle-Baker PK, Lun V, Wiley JP, Aboodarda SJ, MacInnis MJ. The influence of skeletal muscle mitochondria and sex on critical torque and performance fatiguability in humans. J Physiol 2023; 601:5295-5316. [PMID: 37902588 DOI: 10.1113/jp284958] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Accepted: 10/04/2023] [Indexed: 10/31/2023] Open
Abstract
Critical torque (CT) represents the highest oxidative steady state for intermittent knee extensor exercise, but the extent to which it is influenced by skeletal muscle mitochondria and sex is unclear. Vastus lateralis muscle biopsy samples were collected from 12 females and 12 males -matched for relative maximal oxygen uptake normalized to fat-free mass (FFM) (F: 57.3 (7.5) ml (kg FFM)-1 min-1 ; M: 56.8 (7.6) ml (kg FFM)-1 min-1 ; P = 0.856) - prior to CT determination and performance fatiguability trials. Males had a lower proportion of myosin heavy chain (MHC) I isoform (40.6 (18.4)%) compared to females (59.5 (18.9)%; P = 0.021), but MHC IIa and IIx isoform distributions and protein markers of mitochondrial content were not different between sexes (P > 0.05). When normalized to maximum voluntary contraction (MVC), the relative CT (F: 42.9 (8.3)%; M: 37.9 (9.0)%; P = 0.172) and curvature constant, W' (F: 26.6 (11.0) N m s (N m)-1 ; M: 26.4 (6.5) N m s (N m)-1 ; P = 0.962) were not significantly different between sexes. All protein biomarkers of skeletal muscle mitochondrial content, as well as the proportion of MHC I isoform, positively correlated with relative CT (0.48 < r < 0.70; P < 0.05), and the proportion of MHC IIx isoform correlated positively with relative W' (r = 0.57; P = 0.007). Indices of performance fatiguability were not different between males and females for MVC- and CT-controlled trials (P > 0.05). Greater mitochondrial protein abundance was associated with attenuated declines in potentiated twitch torque for exercise at 60% MVC (P < 0.05); however, the influence of mitochondrial protein abundance on performance fatiguability was reduced when exercise was prescribed relative to CT. Whether these findings translate to whole-body exercise requires additional research. KEY POINTS: The quadriceps critical torque represents the highest intensity of intermittent knee extensor exercise for which an oxidative steady state is attainable, but its relationship with skeletal muscle mitochondrial protein abundance is unknown. Matching males and females for maximal oxygen uptake relative to fat-free mass facilitates investigations of sex differences in exercise physiology, but studies that have compared critical torque and performance fatiguability during intermittent knee extensor exercise have not ensured equal aerobic fitness between sexes. Skeletal muscle mitochondrial protein abundance was correlated with critical torque and fatigue resistance for exercise prescribed relative to maximum voluntary contraction but not for exercise performed relative to the critical torque. Differences between sexes in critical torque, skeletal muscle mitochondrial protein abundance and performance fatiguability were not statistically significant. Our results suggest that skeletal muscle mitochondrial protein abundance may contribute to fatigue resistance by influencing the critical intensity of exercise.
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Affiliation(s)
| | - Thomas R Tripp
- Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
| | | | | | - Victor Lun
- Faculty of Kinesiology, University of Calgary Sport Medicine Centre, University of Calgary, Calgary, Alberta, Canada
| | - J Preston Wiley
- Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
- Faculty of Kinesiology, University of Calgary Sport Medicine Centre, University of Calgary, Calgary, Alberta, Canada
| | - S Jalal Aboodarda
- Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
| | - Martin J MacInnis
- Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
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10
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Jones AM. The fourth dimension: physiological resilience as an independent determinant of endurance exercise performance. J Physiol 2023. [PMID: 37606604 DOI: 10.1113/jp284205] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2023] [Accepted: 07/28/2023] [Indexed: 08/23/2023] Open
Abstract
Endurance exercise performance is known to be closely associated with the three physiological pillars of maximal O2 uptake (V ̇ O 2 max $\dot{V}_{{\rm O}_{2}{\rm max}}$ ), economy or efficiency during submaximal exercise, and the fractional utilisation ofV ̇ O 2 max $\dot{V}_{{\rm O}_{2}{\rm max}}$ (linked to metabolic/lactate threshold phenomena). However, while 'start line' values of these variables are collectively useful in predicting performance in endurance events such as the marathon, it is not widely appreciated that these variables are not static but are prone to significant deterioration as fatiguing endurance exercise proceeds. For example, the 'critical power' (CP), which is a composite of the highest achievable steady-state oxidative metabolic rate and efficiency (O2 cost per watt), may fall by an average of 10% following 2 h of heavy intensity cycle exercise. Even more striking is that the extent of this deterioration displays appreciable inter-individual variability, with changes in CP ranging from <1% to ∼32%. The mechanistic basis for such differences in fatigue resistance or 'physiological resilience' are not resolved. However, resilience may be important in explaining superlative endurance performance and it has implications for the physiological evaluation of athletes and the design of interventions to enhance performance. This article presents new information concerning the dynamic plasticity of the three 'traditional' physiological variables and argues that physiological resilience should be considered as an additional component, or fourth dimension, in models of endurance exercise performance.
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Affiliation(s)
- Andrew M Jones
- Department of Public Health and Sport Sciences, University of Exeter Medical School, St Luke's Campus, Exeter, UK
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Ducrocq GP, Al Assad SH, Kouzkouz N, Hureau TJ. The Role of Contraction Mode in Determining Exercise Tolerance, Torque-Duration Relationship, and Neuromuscular Fatigue. Med Sci Sports Exerc 2023; 55:1218-1231. [PMID: 36878018 DOI: 10.1249/mss.0000000000003145] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/08/2023]
Abstract
PURPOSE Critical torque (CT) and work done above it ( W ') are key predictors of exercise performance associated with neuromuscular fatigue. The aim of the present study was to understand the role of the metabolic cost of exercise in determining exercise tolerance, CT and W ', and the mechanisms of neuromuscular fatigue. METHODS Twelve subjects performed four knee extension time trials (6, 8, 10, and 12 min) using eccentric, isometric, or concentric contractions (3-s on/2-s off at 90°·s -1 or 30°·s -1 ) to modulate the metabolic cost of exercise. Exercise performance was quantified by total impulse and mean torque. Critical torque and W ' were determined using the linear relationship between total impulse and contraction time. Cardiometabolic, neuromuscular, and ventilatory responses were quantified. Neuromuscular function was evaluated by maximal voluntary contraction, resting potentiated single/doublet electrical stimulations, and superimposed single electrical stimulation to quantify neuromuscular, peripheral, and central fatigue, respectively. RESULTS Compared with isometric exercise, total impulse (+36% ± 21%; P < 0.001), CT (+27% ± 30%; P < 0.001), and W ' (+67% ± 99%; P < 0.001) were increased during eccentric exercise, whereas total impulse (-25% ± 7%; P < 0.001), critical torque (-26% ± 15%; P < 0.001), and W ' (-18% ± 19%; P < 0.001) were reduced in concentric exercise. Conversely, the metabolic response and the degree of peripheral fatigue were reduced during eccentric exercise, whereas they were increased during concentric exercise. Critical torque was negatively associated with oxygen consumption gain ( R2 = 0.636; P < 0.001), and W ' was negatively associated with rates of neuromuscular and peripheral fatigue indices ( R2 = 0.252-0.880; P < 0.001). CONCLUSIONS The contraction mode influenced both CT and W ', and consequently exercise tolerance, indicating that the metabolic cost of contraction played a key role.
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Affiliation(s)
- Guillaume P Ducrocq
- Mitochondria, Oxidative Stress and Muscular Protection Laboratory (UR 3072), Faculty of Medicine, University of Strasbourg, Strasbourg, FRANCE; European Centre for Education, Research and Innovation in Exercise Physiology (CEERIPE), Faculty of Sport Sciences, University of Strasbourg, Strasbourg, FRANCE
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Poffé C, Robberechts R, Van Thienen R, Hespel P. Exogenous ketosis elevates circulating erythropoietin and stimulates muscular angiogenesis during endurance training overload. J Physiol 2023; 601:2345-2358. [PMID: 37062892 DOI: 10.1113/jp284346] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2023] [Accepted: 04/12/2023] [Indexed: 04/18/2023] Open
Abstract
De novo capillarization is a primary muscular adaptation to endurance exercise training and is crucial to improving performance. Excess training load, however, impedes such beneficial adaptations, yet we recently demonstrated that such downregulation may be counteracted by ketone ester ingestion (KE) post-exercise. Therefore, we investigated whether KE could increase pro-angiogenic factors and thereby stimulate muscular angiogenesis during a 3-week endurance training-overload period involving 10 training sessions/week in healthy, male volunteers. Subjects received either 25 g of a ketone ester (KE, n = 9) or a control drink (CON, n = 9) immediately after each training session and before sleep. In KE, but not in CON, the training intervention increased the number of capillary contacts and the capillary-to-fibre perimeter exchange index by 44% and 42%, respectively. Furthermore, KE also substantially increased vascular endothelial growth factor (VEGF) and endothelial nitric oxide synthase (eNOS) expression both at the protein and at the mRNA level. Serum erythropoietin concentration was concomitantly increased by 26%. Conversely, in CON the training intervention increased only the protein content of eNOS. These data indicate that intermittent exogenous ketosis during endurance overload training stimulates muscular angiogenesis. This likely resulted from a direct stimulation of muscle angiogenesis, which may be at least partly due to stimulation of erythropoietin secretion and elevated VEGF activity, and/or an inhibition of the suppressive effect of overload training on the normal angiogenic response to training. This study provides novel evidence to support the potential of exogenous ketosis to benefit endurance training-induced muscular adaptation. KEY POINTS: Increased capillarization is a primary muscular adaptation to endurance exercise training. However, excess training load may impede such response. We previously observed that intermittent exogenous ketosis by post-exercise and pre-sleep ketone ester ingestion (KE) counteracted physiological dysregulations induced by endurance overload training. Therefore, we investigated whether KE could increase pro-angiogenic factors thereby stimulating muscular angiogenesis during a 3-week endurance training overload period. We show that the overload training period in the presence, but not in the absence, of KE markedly increased muscle capillarization (+40%). This increase was accompanied by higher circulating erythropoietin concentration and stimulation of the pro-angiogenic factors vascular endothelial growth factor and endothelial nitric oxide synthase in skeletal muscle. Collectively, our data indicate that intermittent exogenous ketosis may evolve as a potent nutritional strategy to facilitate recovery from strenuous endurance exercise, thereby stimulating beneficial muscular adaptations.
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Affiliation(s)
- Chiel Poffé
- Exercise Physiology Research Group, Department of Movement Sciences, KU Leuven, Leuven, Belgium
| | - Ruben Robberechts
- Exercise Physiology Research Group, Department of Movement Sciences, KU Leuven, Leuven, Belgium
| | - Ruud Van Thienen
- Exercise Physiology Research Group, Department of Movement Sciences, KU Leuven, Leuven, Belgium
| | - Peter Hespel
- Department of Movement Sciences, KU Leuven, Leuven, Belgium
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Fulton TJ, Sundberg CW, Arney BE, Hunter SK. Sex Differences in the Speed-Duration Relationship of Elite Runners across the Lifespan. Med Sci Sports Exerc 2023; 55:911-919. [PMID: 36728809 PMCID: PMC10106388 DOI: 10.1249/mss.0000000000003112] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
PURPOSE To determine if the speed-duration relationship is altered with age and sex of elite Master's runners. METHODS The world's top 10 performances for men and women in three events (800, 1500, and 5000 m) across six age groups (18-34 yr, 40-49 yr, 50-59 yr, 60-69 yr, 70-79 yr, and 80-89 yr) were analyzed from public data to establish theoretical models of the speed-duration relationship. Critical speed (CS) and the curvature constant ( D ') were estimated by fitting the average speeds and performance times with a two-parameter hyperbolic model. RESULTS Critical speed expressed relative to the 18- to 34-yr-olds, declined with age (92.2% [40-49] to 55.2% [80-89]; P < 0.001), and absolute CS was higher in men than women within each age group ( P < 0.001). The percent difference in CS between the men and women progressively increased across age groups (10.8% [18-34] to 15.5% [80-89]). D ' was lower in women than men in the 60-69 yr, 70-79 yr, and 80-89 yr age groups ( P < 0.001), but did not differ in the 18-34 yr, 40-49 yr, or 50-59 yr age groups. CONCLUSIONS Critical speed progressively decreased with age, likely due to age-related decrements in several physiological systems that cause reduced aerobic capacity. The mechanism for the larger sex difference in CS in the older age groups is unknown but may indicate physiological differences that occur with aging and/or historical sociological factors that have reduced participation opportunities of older female runners resulting in a more limited talent pool.
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Affiliation(s)
- Timothy J. Fulton
- Exercise Science Program, Department of Physical Therapy, Marquette University, Milwaukee, WI
| | - Christopher W. Sundberg
- Exercise Science Program, Department of Physical Therapy, Marquette University, Milwaukee, WI
- Athletic and Human Performance Research Center, Marquette University, Milwaukee, WI
| | - Blaine E. Arney
- Exercise Science Program, Department of Physical Therapy, Marquette University, Milwaukee, WI
| | - Sandra K. Hunter
- Exercise Science Program, Department of Physical Therapy, Marquette University, Milwaukee, WI
- Athletic and Human Performance Research Center, Marquette University, Milwaukee, WI
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14
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Burnley M. Invited review: The speed-duration relationship across the animal kingdom. Comp Biochem Physiol A Mol Integr Physiol 2023; 279:111387. [PMID: 36740171 DOI: 10.1016/j.cbpa.2023.111387] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Revised: 01/25/2023] [Accepted: 02/01/2023] [Indexed: 02/05/2023]
Abstract
The parameters of the hyperbolic speed-duration relationship (the asymptote critical speed, CS, and the curvature constant, D') provide estimates of the maximal steady state speed (CS) and the distance an animal can run, swim, or fly at speeds above CS before it is forced to slow down or stop (D'). The speed-duration relationship has been directly studied in humans, horses, mice and rats. The technical difficulties with treadmill running in dogs and the relatively short greyhound race durations means that, perhaps surprisingly, it has not been assessed in dogs. The endurance capabilities of lizards, crabs and salamanders has also been measured, and the speed-duration relationship can be calculated from these data. These analyses show that 1) raising environmental temperature from 25 °C to 40 °C in lizards can double the CS with no change in D'; 2) that lungless salamanders have an extremely low critical speed due, most likely, to O2 diffusion limitations associated with cutaneous respiration; and 3) the painted ghost crab possesses the highest endurance parameter ratio (D'/CS) yet recorded (470 s), allowing it to maintain high speeds for extended periods. Although the speed-duration relationship has not been measured in fish, the sustainable swimming speed has been quantified in a range of species and is conceptually similar to the maximal steady state in humans. The high aerobic power of birds and low metabolic cost of transport during flight permits the extreme feats of endurance observed in bird migrations. However, the parameters of the avian speed-duration relationship have not been quantified.
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Affiliation(s)
- Mark Burnley
- School of Sport, Exercise and Health Sciences, Loughborough University, Leicestershire, UK.
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15
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Vinetti G, Pollastri L, Lanfranconi F, Bruseghini P, Taboni A, Ferretti G. Modeling the Power-Duration Relationship in Professional Cyclists During the Giro d'Italia. J Strength Cond Res 2023; 37:866-871. [PMID: 36026464 DOI: 10.1519/jsc.0000000000004350] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2021] [Accepted: 06/12/2022] [Indexed: 11/08/2022]
Abstract
ABSTRACT Vinetti, G, Pollastri, L, Lanfranconi, F, Bruseghini, P, Taboni, A, and Ferretti, G. Modeling the power-duration relationship in professional cyclists during the Giro d'Italia. J Strength Cond Res 37(4): 866-871, 2023-Multistage road bicycle races allow the assessment of maximal mean power output (MMP) over a wide spectrum of durations. By modeling the resulting power-duration relationship, the critical power ( CP ) and the curvature constant ( W' ) can be calculated and, in the 3-parameter (3-p) model, also the maximal instantaneous power ( P0 ). Our aim is to test the 3-p model for the first time in this context and to compare it with the 2-parameter (2-p) model. A team of 9 male professional cyclists participated in the 2014 Giro d'Italia with a crank-based power meter. The maximal mean power output between 10 seconds and 10 minutes were fitted with 3-p, whereas those between 1 and 10 minutes with the 2- model. The level of significance was set at p < 0.05. 3-p yielded CP 357 ± 29 W, W' 13.3 ± 4.2 kJ, and P0 1,330 ± 251 W with a SEE of 10 ± 5 W, 3.0 ± 1.7 kJ, and 507 ± 528 W, respectively. 2-p yielded a CP and W' slightly higher (+4 ± 2 W) and lower (-2.3 ± 1.1 kJ), respectively ( p < 0.001 for both). Model predictions were within ±10 W of the 20-minute MMP of time-trial stages. In conclusion, during a single multistage racing event, the 3-p model accurately described the power-duration relationship over a wider MMP range without physiologically relevant differences in CP with respect to 2-p, potentially offering a noninvasive tool to evaluate competitive cyclists at the peak of training.
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Affiliation(s)
- Giovanni Vinetti
- Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy
- Institute of Mountain Emergency Medicine, Eurac Research, Bolzano, Italy
| | - Luca Pollastri
- Pentavis, Laboratory of Sport Sciences, Lecco, Italy
- School of Medicine and Surgery, University of Milano-Bicocca, Monza, Italy; and
| | | | - Paolo Bruseghini
- Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy
| | - Anna Taboni
- Department of Anesthesiology, Pharmacology, Intensive Care and Emergencies, University of Geneva, Geneva, Switzerland
| | - Guido Ferretti
- Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy
- Department of Anesthesiology, Pharmacology, Intensive Care and Emergencies, University of Geneva, Geneva, Switzerland
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16
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Interaction of Factors Determining Critical Power. Sports Med 2023; 53:595-613. [PMID: 36622556 PMCID: PMC9935749 DOI: 10.1007/s40279-022-01805-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/16/2022] [Indexed: 01/10/2023]
Abstract
The physiological determinants of high-intensity exercise tolerance are important for both elite human performance and morbidity, mortality and disease in clinical settings. The asymptote of the hyperbolic relation between external power and time to task failure, critical power, represents the threshold intensity above which systemic and intramuscular metabolic homeostasis can no longer be maintained. After ~ 60 years of research into the phenomenon of critical power, a clear understanding of its physiological determinants has emerged. The purpose of the present review is to critically examine this contemporary evidence in order to explain the physiological underpinnings of critical power. Evidence demonstrating that alterations in convective and diffusive oxygen delivery can impact upon critical power is first addressed. Subsequently, evidence is considered that shows that rates of muscle oxygen utilisation, inferred via the kinetics of pulmonary oxygen consumption, can influence critical power. The data reveal a clear picture that alterations in the rates of flux along every step of the oxygen transport and utilisation pathways influence critical power. It is also clear that critical power is influenced by motor unit recruitment patterns. On this basis, it is proposed that convective and diffusive oxygen delivery act in concert with muscle oxygen utilisation rates to determine the intracellular metabolic milieu and state of fatigue within the myocytes. This interacts with exercising muscle mass and motor unit recruitment patterns to ultimately determine critical power.
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17
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Green ES, Williams ER, Feito Y, Jenkins NT. Physiological and Anthropometric Differences Among Endurance, Strength, and High-Intensity Functional Training Participants: A Cross-Sectional Study. RESEARCH QUARTERLY FOR EXERCISE AND SPORT 2023; 94:131-142. [PMID: 35302436 DOI: 10.1080/02701367.2021.1947468] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Accepted: 06/10/2021] [Indexed: 06/14/2023]
Abstract
Purpose: We compared aerobic capacity (V˙O2max), mitochondrial capacity (mV˙O2), anaerobic power, strength, and muscle endurance in healthy, active men from strength (STR), endurance (END) and high-intensity functional training (HIFT) backgrounds. Methods: Twenty-four men (n = 8/group) completed a cycle ergometer test to determine V˙O2max, followed by a 3-min all-out test to determine peak (PP) and end power (EP), and to estimate anaerobic [work done above EP (WEP)] and aerobic work capacity. Strength was determined by knee extensor maximal voluntary contraction at various flexion angles. The endurance index (EI) of the vastus lateralis (VL) was assessed by measuring muscle contraction acceleration during electrical twitch mechanomyography. mV˙O2max of the VL was assessed using near-infrared spectroscopy to estimate muscle oxygen consumption during transient femoral artery occlusions. Results: V˙O2max was significantly different among groups (p < .05). PP was significantly higher in HIFT and STR versus END (p < .05). EP was significantly higher in HIFT and END compared to STR (p < .05). WEP was significantly higher in STR compared to END (p < .05), whereas total work done was significantly higher in HIFT and END compared to STR (p < .05). mV˙O2max and EI were comparable between HIFT and END but significantly lower in STR versus END (p < .05). Torque production was significantly lower in END compared to STR and HIFT at all flexion angles (p < .05), with no difference between STR and HIFT. Conclusion: HIFT participants can exert similar power outputs and absolute strength compared to strength focused participants but exhibit fatigue resistance and mitochondrial capacity comparable to those who train for endurance.
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18
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Ross M, Kargl CK, Ferguson R, Gavin TP, Hellsten Y. Exercise-induced skeletal muscle angiogenesis: impact of age, sex, angiocrines and cellular mediators. Eur J Appl Physiol 2023:10.1007/s00421-022-05128-6. [PMID: 36715739 DOI: 10.1007/s00421-022-05128-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2022] [Accepted: 12/25/2022] [Indexed: 01/31/2023]
Abstract
Exercise-induced skeletal muscle angiogenesis is a well-known physiological adaptation that occurs in humans in response to exercise training and can lead to endurance performance benefits, as well as improvements in cardiovascular and skeletal tissue health. An increase in capillary density in skeletal muscle improves diffusive oxygen exchange and waste extraction, and thus greater fatigue resistance, which has application to athletes but also to the general population. Exercise-induced angiogenesis can significantly contribute to improvements in cardiovascular and metabolic health, such as the increase in muscle glucose uptake, important for the prevention of diabetes. Recently, our understanding of the mechanisms by which angiogenesis occurs with exercise has grown substantially. This review will detail the biochemical, cellular and biomechanical signals for exercise-induced skeletal muscle angiogenesis, including recent work on extracellular vesicles and circulating angiogenic cells. In addition, the influence of age, sex, exercise intensity/duration, as well as recent observations with the use of blood flow restricted exercise, will also be discussed in detail. This review will provide academics and practitioners with mechanistic and applied evidence for optimising training interventions to promote physical performance through manipulating capillarisation in skeletal muscle.
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Affiliation(s)
- Mark Ross
- School of Energy, Geoscience, Infrastructure and Society, Heriot-Watt University, Edinburgh, Scotland, UK.
| | - Christopher K Kargl
- Department of Sports Medicine and Nutrition, University of Pittsburgh, Pittsburgh, USA.,Department of Health and Kinesiology, Max E. Wastl Human Performance Laboratory, Purdue University, West Lafayette, USA
| | - Richard Ferguson
- School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, UK
| | - Timothy P Gavin
- Department of Health and Kinesiology, Max E. Wastl Human Performance Laboratory, Purdue University, West Lafayette, USA
| | - Ylva Hellsten
- Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark
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19
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Fenuta AM, Drouin PJ, Kohoko ZIN, Lynn MJT, Tschakovsky ME. Does a single bout maximal effort forearm exercise test for determining critical impulse result in maximal oxygen delivery and consumption in men? A randomized crossover trial. Appl Physiol Nutr Metab 2023; 48:293-306. [PMID: 36645882 DOI: 10.1139/apnm-2022-0317] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
In a single bout maximal effort isometric forearm handgrip exercise test (maximal effort exercise test, MXT), contraction impulse exhibits exponential decay to an asymptote equivalent to critical impulse (CI). It is unknown whether oxygen delivery (O2del) and consumption (V˙O2) achieved at CI are maximal. Healthy men participated in a randomized crossover trial at Queen's University (Kingston, ON) between October 2017-May 2018. Participants completed an MXT and forearm incremental exercise test to limit of tolerance (IET-LOT) (7 completed MXT followed by IET-LOT vs. 4 completed IET-LOT followed by MXT) within a 2 week period. Data are presented as mean ± standard deviation. Maximal forearm blood flow (FBF) and O2del were not different in 11 men (21 ± 2.5 years) between MXT and IET-LOT (FBF = 473.8 ± 132.2 mL/min vs. 502.3 ± 152.3 mL/min; P = 0.482, ηp2 = 0.015; O2del = 85.2 ± 23.5 mL/min vs. 92.2 ± 37.0 mL/min; P = 0.456, ηp2 = 0.012). However, MXT resulted in greater maximal V˙O2 than IET-LOT (44.5 ± 15.2 mL/min > 36.8 ± 11.4 mL/min; P = 0.007, ηp2 = 0.09), due to greater oxygen extraction (54.0 ± 10.0% > 44.4 ± 8.6%; P = 0.021, ηp2 = 0.185). As CI was 88.6 ± 8.2% of IET-LOT contraction impulse, maximal O2 cost of contractions in MXT was greater than IET-LOT (0.45 ± 0.14 mL/min/Ns > 0.33 ± 0.09 mL/min/Ns; P < 0.001, ηp2 = 0.166). In healthy men, MXT identifying CI results in similar peak oxygen delivery but greater peak V˙O2 via increased extraction compared to an IET-LOT, indicating increased oxygen cost. MXT-CI may better estimate maximal V˙O2 than traditional IET-LOT for this exercise modality.
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Affiliation(s)
- Alyssa M Fenuta
- School of Kinesiology and Health Studies, Queen's University, Kingston, Ontario, K7L 3N6, Canada
| | - Patrick J Drouin
- School of Kinesiology and Health Studies, Queen's University, Kingston, Ontario, K7L 3N6, Canada
| | - Zach I N Kohoko
- School of Kinesiology and Health Studies, Queen's University, Kingston, Ontario, K7L 3N6, Canada
| | - Mytchel J T Lynn
- School of Kinesiology and Health Studies, Queen's University, Kingston, Ontario, K7L 3N6, Canada
| | - Michael E Tschakovsky
- School of Kinesiology and Health Studies, Queen's University, Kingston, Ontario, K7L 3N6, Canada
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20
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Smith NDW, Scott BR, Girard O, Peiffer JJ. Aerobic Training With Blood Flow Restriction for Endurance Athletes: Potential Benefits and Considerations of Implementation. J Strength Cond Res 2022; 36:3541-3550. [PMID: 34175880 DOI: 10.1519/jsc.0000000000004079] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
ABSTRACT Smith, NDW, Scott, BR, Girard, O, and Peiffer, JJ. Aerobic training with blood flow restriction for endurance athletes: potential benefits and considerations of implementation. J Strength Cond Res 36(12): 3541-3550, 2022-Low-intensity aerobic training with blood flow restriction (BFR) can improve maximal oxygen uptake, delay the onset of blood lactate accumulation, and may provide marginal benefits to economy of motion in untrained individuals. Such a training modality could also improve these physiological attributes in well-trained athletes. Indeed, aerobic BFR training could be beneficial for those recovering from injury, those who have limited time for training a specific physiological capacity, or as an adjunct training stimulus to provide variation in a program. However, similarly to endurance training without BFR, using aerobic BFR training to elicit physiological adaptations in endurance athletes will require additional considerations compared with nonendurance athletes. The objective of this narrative review is to discuss the acute and chronic aspects of aerobic BFR exercise for well-trained endurance athletes and highlight considerations for its effective implementation. This review first highlights key physiological capacities of endurance performance. The acute and chronic responses to aerobic BFR exercise and their impact on performance are then discussed. Finally, considerations for prescribing and monitoring aerobic BFR exercise in trained endurance populations are addressed to challenge current views on how BFR exercise is implemented.
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Affiliation(s)
- Nathan D W Smith
- Exercise Science, Murdoch University, Perth, Western Australia.,Murdoch Applied Sports Science Laboratory, Murdoch University, Perth, Western Australia
| | - Brendan R Scott
- Murdoch Applied Sports Science Laboratory, Murdoch University, Perth, Western Australia.,Center for Healthy Ageing, Murdoch University, Perth, Western Australia ; and
| | - Olivier Girard
- School of Human Sciences (Exercise and Sport Science), The University of Western Australia, Perth, Western Australia
| | - Jeremiah J Peiffer
- Murdoch Applied Sports Science Laboratory, Murdoch University, Perth, Western Australia.,Center for Healthy Ageing, Murdoch University, Perth, Western Australia ; and
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21
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Richard NA, Koehle MS. Influence and Mechanisms of Action of Environmental Stimuli on Work Near and Above the Severe Domain Boundary (Critical Power). SPORTS MEDICINE - OPEN 2022; 8:42. [PMID: 35347469 PMCID: PMC8960528 DOI: 10.1186/s40798-022-00430-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/24/2021] [Accepted: 02/26/2022] [Indexed: 11/10/2022]
Abstract
Abstract
The critical power (CP) concept represents the uppermost rate of steady state aerobic metabolism during work. Work above CP is limited by a fixed capacity (W′) with exercise intensity being an accelerant of its depletion rate. Exercise at CP is a considerable insult to homeostasis and any work done above it will rapidly become intolerable. Humans live and exercise in situations of hypoxia, heat, cold and air pollution all of which impose a new environmental stress in addition to that of exercise. Hypoxia disrupts the oxygen cascade and consequently aerobic energy production, whereas heat impacts the circulatory system’s ability to solely support exercise performance. Cold lowers efficiency and increases the metabolic cost of exercise, whereas air pollution negatively impacts the respiratory system. This review will examine the effects imposed by environmental conditions on CP and W′ and describe the key physiological mechanisms which are affected by the environment.
Graphical Abstract
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22
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Liu Y, Christensen PM, Hellsten Y, Gliemann L. Effects of Exercise Training Intensity and Duration on Skeletal Muscle Capillarization in Healthy Subjects: A Meta-analysis. Med Sci Sports Exerc 2022; 54:1714-1728. [PMID: 35522254 DOI: 10.1249/mss.0000000000002955] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
PURPOSE This study aimed to investigate the effect of intensity and duration of continuous and interval exercise training on capillarization in skeletal muscle of healthy adults. METHODS PubMed and Web of Science were searched from inception to June 2021. Eligibility criteria for studies were endurance exercise training >2 wk in healthy adults, and the capillary to fiber ratio (C:F) and/or capillary density (CD) reported. Meta-analyses were performed, and subsequent subgroup analyses were conducted by the characteristics of participants and training scheme. RESULTS Fifty-seven trials from 38 studies were included (10%/90%, athletic/sedentary). C:F was measured in 391 subjects from 47 trials, whereas CD was measured in 428 subjects from 50 trials. Exercise training increased C:F (mean difference, 0.33 (95% confidence interval, 0.30-0.37)) with low heterogeneity ( I2 = 45.08%) and CD (mean difference, 49.8 (36.9-62.6) capillaries per millimeter squared) with moderate heterogeneity ( I2 = 68.82%). Compared with low-intensity training (<50% of maximal oxygen consumption (V̇O 2max )), 21% higher relative change in C:F was observed after continuous moderate-intensity training (50%-80% of V̇O 2max ) and 54% higher change after interval training with high intensity (80%-100% of V̇O 2max ) in sedentary subjects. The magnitude of capillary growth was not dependent on training intervention duration. In already trained subjects, no additional increase in capillarization was observed with various types of training. CONCLUSIONS In sedentary subjects, continuous moderate-intensity training and interval training with high intensity lead to increases in capillarization, whereas low-intensity training has less effect. Within the time frame studied, no effect on capillarization was established regarding training duration in sedentary subjects. The meta-analysis highlights the need for further studies in athlete groups to discern if increased capillarization can be obtained, and if so, which combination is optimal (time vs intensity).
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Affiliation(s)
| | | | - Ylva Hellsten
- The August Krogh Section for Human Physiology, Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, DENMARK
| | - Lasse Gliemann
- The August Krogh Section for Human Physiology, Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, DENMARK
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23
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Critical Power, Work Capacity, and Recovery Characteristics of Team-Pursuit Cyclists. Int J Sports Physiol Perform 2022; 17:1606-1613. [PMID: 36068071 DOI: 10.1123/ijspp.2021-0478] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Revised: 06/30/2022] [Accepted: 07/06/2022] [Indexed: 11/18/2022]
Abstract
PURPOSE Leading a 4-km team pursuit (TP) requires high-intensity efforts above critical power (CP) that deplete riders' finite work capacity (W'), whereas riders following in the aerodynamic draft may experience some recovery due to reduced power demands. This study aimed to determine how rider ability and CP and W' measures impact TP performance and the extent to which W' can reconstitute during recovery positions in a TP race. METHODS Three TP teams, each consisting of 4 males, completed individual performance tests to determine their CP and W'. Teams were classified based on their performance level as international (INT), national (NAT), or regional (REG). Each team performed a TP on an indoor velodrome (INT: 3:49.9; NAT: 3:56.7; and REG: 4:05.4; min:s). Ergometer-based TP simulations with an open-ended interval to exhaustion were performed to measure individual ability to reconstitute W' at 25 to 100 W below CP. RESULTS The INT team possessed higher CP (407 [4] W) than both NAT (381 [13] W) and REG (376 [15] W) (P < .05), whereas W' was similar between teams (INT: 27.2 [2.8] kJ; NAT: 29.3 [2.4] kJ; and REG: 28.8 [1.6] kJ; P > .05). The INT team expended 104% (5%) of their initial W' during the TP and possessed faster rates of recovery than NAT and REG at 25 and 50 W below CP (P < .05). CONCLUSIONS The CP and rate of W' reconstitution have a greater impact on TP performance than W' magnitude and can differentiate TP performance level.
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24
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Kontro H, Bertagnolli C, Murias JM, MacInnis MJ. Impairment in maximal lactate steady state after carbon monoxide inhalation is related to training status. Exp Physiol 2022; 107:1265-1282. [PMID: 36029041 DOI: 10.1113/ep090642] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Accepted: 08/17/2022] [Indexed: 11/08/2022]
Abstract
NEW FINDINGS What is the central question of this study? What is the effect of an elevated COHb concentration following carbon monoxide inhalation on the maximal lactate steady state (MLSS) in humans and is this effect dependent on aerobic fitness? What is the main finding and its importance? An elevated COHb concentration intensified physiological responses to exercise at the MLSS- including heart rate, ventilation, and peripheral fatigue-in all participants and reduced the MLSS (i.e., destabilized the blood lactate concentration) in trained but not untrained males and females. ABSTRACT This study investigated whether a lower effective [Hb], induced by carbon monoxide (CO) inhalation, reduces the peak oxygen uptake (V̇O2 peak) and the maximal lactate steady state (MLSS) and whether training status explains individual variation in these impairments. Healthy young participants completed two ramp incremental tests (n = 20 [10 female]) and two trials at MLSS (n = 16 [8 female]) following CO rebreathe tests and sham procedures (SHAM) in random orders. All fitness variables were normalized to fat-free mass (FFM) to account for sex-related differences in body composition, and males and females were matched for aerobic fitness. The V̇O2 peak (mean [SD]: -4.2 [3.7]%), peak power output (-3.3 [2.2]%), and respiratory compensation point (-6.3 [4.5]%) were reduced in CO compared with SHAM (P < 0.001 for all), but the gas exchange threshold (-3.3 [7.1]%) was not (P = 0.077). Decreases in V̇O2 peak (r = -0.45; P = 0.047) and peak power output (r = -0.49; P = 0.029) in CO were correlated with baseline aerobic fitness. Compared to SHAM, physiological and perceptual indicators of exercise-related stress were exacerbated by CO while cycling at MLSS. Notably, the mean blood lactate concentration ([La]) increased (i.e., Δ[La] > 1.0 mM) between 10 min (5.5 [1.4] mM) and 30 min (6.8 [1.3] mM; P = 0.026) in CO, with 9/16 participants classified as unstable. These unstable participants had a higher V̇O2 peak (66.2 [8.5] vs. 56.4 [8.8] mL·kg FFM-1 ·min-1 , P = 0.042) and V̇O2 at MLSS (55.8 vs. 44.3 mL·kg FFM-1 ·min-1 , P = 0.006) compared to the stable group. In conclusion, a reduced O2 -carrying capacity decreased maximal and submaximal exercise performance, with higher aerobic fitness associated with greater impairments in both. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Hilkka Kontro
- Faculty of Kinesiology, Human Performance Lab, University of Calgary, Canada
| | - Craig Bertagnolli
- Faculty of Kinesiology, Human Performance Lab, University of Calgary, Canada
| | - Juan M Murias
- Faculty of Kinesiology, Human Performance Lab, University of Calgary, Canada
| | - Martin J MacInnis
- Faculty of Kinesiology, Human Performance Lab, University of Calgary, Canada
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25
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Performance prediction, pacing profile and running pattern of elite 1-h track running events. SPORT SCIENCES FOR HEALTH 2022. [DOI: 10.1007/s11332-022-00945-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/15/2022]
Abstract
Abstract
Purpose
This study aimed at comparing the predictive accuracy of the power law (PL), 2-parameter hyperbolic (HYP) and linear (LIN) models on elite 1-h track running performance, and evaluating pacing profile and running pattern of the men’s best two 1-h track running performances of all times.
Methods
The individual running speed–distance profile was obtained for nine male elite runners using the three models. Different combinations of personal bests times (3000 m-marathon) were used to predict performance. The level of absolute agreement between predicted and actual performance was evaluated using intraclass correlation coefficient (ICC), paired t test and Bland–Altman analysis. A video analysis was performed to assess pacing profile and running pattern.
Results
Regardless of the predictors used, no significant differences (p > 0.05) between predicted and actual performances were observed for the PL model. A good agreement was found for the HYP and LIN models only when the half-marathon was the longest event predictor used (ICC = 0.718–0.737, p < 0.05). Critical speed (CS) was highly dependent on the predictors used. Unlike CS, PLV20 (i.e., the running speed corresponding to a 20-min performance estimated using the PL model) was associated with 1-h track running performances (r = 0.722–0.807, p < 0.05). An even pacing profile with minimal changes of step length and frequency was observed.
Conclusions
The PL model may offer the more realistic 1-h track running performance prediction among the models investigated. An even pacing might be the best strategy for succeeding in such running events.
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26
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Valenzuela PL, Mateo-March M, Muriel X, Zabala M, Lucia A, Barranco-Gil D, Millet GP, Brocherie F, Burtscher J, Burtscher M, Ryan BJ, Gioscia-Ryan RA, Perrey S, Rodrigo-Carranza V, González-Mohíno F, González-Ravé JM, Santos-Concejero J, Denadai BS, Greco CC, Casado A, Foster C, Mazzolari R, Baldrighi GN, Pastorio E, Malatesta D, Patoz A, Borrani F, Ives SJ, DeBlauw JA, Dantas de Lucas R, Borszcz FK, Fernandes Nascimento EM, Antonacci Guglielmo LG, Turnes T, Jaspers RT, van der Zwaard S, Lepers R, Louis J, Meireles A, de Souza HLR, de Oliveira GT, dos Santos MP, Arriel RA, Marocolo M, Hunter B, Meyler S, Muniz-Pumares D, Ferreira RM, Sogard AS, Carter SJ, Mickleborough TD, Saborosa GP, de Oliveira Freitas RD, Alves dos Santos PS, de Souza Ferreira JP, de Assis Manoel F, da Silva SF, Triska C, Karsten B, Sanders D, Lipksi ES, Spindler DJ, Hesselink MKC, Zacca R, Goethel MF, Pyne DB, Wood BM, Allen PE, Gabelhausen JL, Keller AM, Lige MT, Oumsang AS, Smart GL, Paris HL, Dewolf AH, Toffoli G, Martinez-Gonzalez B, Marcora SM, Terson de Paleville D, Fernandes RJ, Soares SM, Abraldes JA, Matta G, Bossi AH, McCarthy DG, Bostad W, Gibala J, Vagula M. Commentaries on Viewpoint: Using V̇o 2max as a marker of training status in athletes - can we do better? J Appl Physiol (1985) 2022; 133:148-164. [PMID: 35819399 DOI: 10.1152/japplphysiol.00224.2022] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Affiliation(s)
- Pedro L Valenzuela
- Grupo de Investigación en Actividad física y Salud (PaHerg), Instituto de Investigación Hospital 12 de Octubre (imas12), Madrid, Spain
| | - Manuel Mateo-March
- Faculty of Sport Sciences, Universidad Europea de Madrid, Madrid, Spain,Sport Science Department. Universidad Miguel Hernández, Elche, Spain
| | - Xabier Muriel
- Human Performance and Sports Science Laboratory, Faculty of Sport Sciences, University of Murcia, Murcia, Spain
| | - Mikel Zabala
- Department of Physical Education & Sport, Faculty of Sport Sciences, University of Granada, Granada, Spain
| | - Alejandro Lucia
- Grupo de Investigación en Actividad física y Salud (PaHerg), Instituto de Investigación Hospital 12 de Octubre (imas12), Madrid, Spain,Faculty of Sport Sciences, Universidad Europea de Madrid, Madrid, Spain
| | | | - Grégoire P Millet
- Institute of Sport Sciences, University of Lausanne, Lausanne, Switzerland
| | - Franck Brocherie
- Laboratory Sport, Expertise and Performance (EA 7370), French Institute of Sport (INSEP), Paris, France
| | - Johannes Burtscher
- Institute of Sport Sciences, University of Lausanne, Lausanne, Switzerland
| | - Martin Burtscher
- Department of Sport Science, University of Innsbruck, Innsbruck, Austria
| | - Benjamin J Ryan
- Thermal and Mountain Medicine Division, US Army Research Institute of Environmental Medicine, Natick, Massachusetts
| | | | - Stephane Perrey
- EuroMov Digital Health in Motion, University of Montpellier, Montpellier, France
| | | | - Fernando González-Mohíno
- Sport Training Lab, University of Castilla-La Mancha, Toledo, Spain,Facultad de Ciencias de la Vida y de la Naturaleza, Universidad Nebrija, Madrid, Spain
| | | | - Jordan Santos-Concejero
- Department of Physical Education and Sport, University of the Basque Country UPV/EHU, Vitoria-Gasteiz, Spain
| | - Benedito S Denadai
- Human Performance Laboratory, São Paulo State University, Rio Claro, Brazil
| | - Camila C Greco
- Human Performance Laboratory, São Paulo State University, Rio Claro, Brazil
| | - Arturo Casado
- Center for Sport Studies, Rey Juan Carlos University, Madrid, Spain
| | - Carl Foster
- University of Wisconsin-La Crosse, La Crosse, Wisconsin
| | - Raffaele Mazzolari
- Department of Physical Education and Sport, University of the Basque Country (UPV/EHU), Vitoria-Gasteiz, Spain,Department of Molecular Medicine, University of Pavia, Pavia, Italy
| | - Giulia Nicole Baldrighi
- Department of Brain and Behavioural Sciences − Medical and Genomic Statistics Unit, University of Pavia, Pavia, Italy
| | - Elisa Pastorio
- Department of Molecular Medicine, University of Pavia, Pavia, Italy,Department of Biomedical Sciences for Health, University of Milan, Milan, Italy
| | - Davide Malatesta
- Institute of Sport Sciences of University of Lausanne (ISSUL), University of Lausanne, Lausanne, Switzerland
| | - Aurélien Patoz
- Institute of Sport Sciences of University of Lausanne (ISSUL), University of Lausanne, Lausanne, Switzerland
| | - Fabio Borrani
- Institute of Sport Sciences of University of Lausanne (ISSUL), University of Lausanne, Lausanne, Switzerland
| | - Stephen J Ives
- Health and Human Physiological Sciences, Skidmore College, Saratoga Springs, New York
| | - Justin A DeBlauw
- Health and Human Physiological Sciences, Skidmore College, Saratoga Springs, New York
| | | | | | | | | | - Tiago Turnes
- Physical Effort Laboratory, Federal University of Santa Catarina, Florianopolis, Brazil
| | - Richard T Jaspers
- Department of Human Movement Sciences, Amsterdam Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands,Laboratory for Myology, Department of Human Movement Sciences, Amsterdam Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
| | - Stephan van der Zwaard
- Department of Human Movement Sciences, Amsterdam Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands,Laboratory for Myology, Department of Human Movement Sciences, Amsterdam Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands,Leiden Institute of Advanced Computer Science, Leiden University, Leiden, The Netherlands
| | - Romuald Lepers
- INSERM UMR1093 CAPS, Faculty of Sport Sciences, University of Bourgogne Franche-Comté, Dijon, France
| | - Julien Louis
- Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, United Kingdom
| | - Anderson Meireles
- Physiology and Human Performance Research Group, Department of Physiology, Federal University of Juiz de Fora, Juiz de Fora, Brazil
| | - Hiago L. R. de Souza
- Physiology and Human Performance Research Group, Department of Physiology, Federal University of Juiz de Fora, Juiz de Fora, Brazil
| | - Géssyca T de Oliveira
- Physiology and Human Performance Research Group, Department of Physiology, Federal University of Juiz de Fora, Juiz de Fora, Brazil
| | - Marcelo P dos Santos
- Physiology and Human Performance Research Group, Department of Physiology, Federal University of Juiz de Fora, Juiz de Fora, Brazil
| | - Rhaí A Arriel
- Physiology and Human Performance Research Group, Department of Physiology, Federal University of Juiz de Fora, Juiz de Fora, Brazil
| | - Moacir Marocolo
- Physiology and Human Performance Research Group, Department of Physiology, Federal University of Juiz de Fora, Juiz de Fora, Brazil
| | - B Hunter
- Department of Psychology, Sport, and Geography, School of Life and Medical Sciences, University of Hertfordshire, Hatfield, United Kingdom
| | - S Meyler
- Department of Psychology, Sport, and Geography, School of Life and Medical Sciences, University of Hertfordshire, Hatfield, United Kingdom
| | - D Muniz-Pumares
- Department of Psychology, Sport, and Geography, School of Life and Medical Sciences, University of Hertfordshire, Hatfield, United Kingdom
| | - Renato M Ferreira
- Aquatic Activities Research Group, Department of Physical Education, Federal University of Ouro Preto, Ouro Preto, Brazil
| | - Abigail S Sogard
- Department of Kinesiology, School of Public Health-Bloomington, Indiana University, Bloomington, Indiana
| | - Stephen J Carter
- Department of Kinesiology, School of Public Health-Bloomington, Indiana University, Bloomington, Indiana,Indiana University Melvin and Bren Simon Comprehensive Cancer Center, Indianapolis, Indiana
| | - Timothy D Mickleborough
- Department of Kinesiology, School of Public Health-Bloomington, Indiana University, Bloomington, Indiana
| | - Guilherme Pereira Saborosa
- Study Group and Research in Neuromuscular Responses, University of Lavras, Lavras, Brazil,Postgraduate Program in Nutrition and Health, University of Lavras, Lavras, Brazil
| | - Raphael Dinalli de Oliveira Freitas
- Study Group and Research in Neuromuscular Responses, University of Lavras, Lavras, Brazil,Postgraduate Program in Nutrition and Health, University of Lavras, Lavras, Brazil
| | - Paula Souza Alves dos Santos
- Study Group and Research in Neuromuscular Responses, University of Lavras, Lavras, Brazil,Postgraduate Program in Nutrition and Health, University of Lavras, Lavras, Brazil
| | - João Pedro de Souza Ferreira
- Study Group and Research in Neuromuscular Responses, University of Lavras, Lavras, Brazil,Postgraduate Program in Nutrition and Health, University of Lavras, Lavras, Brazil
| | | | - Sandro Fernandes da Silva
- Study Group and Research in Neuromuscular Responses, University of Lavras, Lavras, Brazil,Postgraduate Program in Nutrition and Health, University of Lavras, Lavras, Brazil
| | - Christoph Triska
- Institute of Sport Science, Centre for Sport Science and University Sports, University of Vienna, Vienna, Austria,Leistungssport Austria, Brunn am Gebirge, Austria
| | - Bettina Karsten
- European University of Applied Sciences (EUFH), Berlin, Germany
| | - Dajo Sanders
- Department of Nutrition and Movement Sciences, NUTRIM School for Nutrition and Translational Research in Metabolism, Maastricht University Medical Center+, Maastricht, The Netherlands
| | - Elliot S Lipksi
- Department of Nutrition and Movement Sciences, NUTRIM School for Nutrition and Translational Research in Metabolism, Maastricht University Medical Center+, Maastricht, The Netherlands
| | - David J Spindler
- Department of Nutrition and Movement Sciences, NUTRIM School for Nutrition and Translational Research in Metabolism, Maastricht University Medical Center+, Maastricht, The Netherlands
| | - Matthijs K. C. Hesselink
- Department of Nutrition and Movement Sciences, NUTRIM School for Nutrition and Translational Research in Metabolism, Maastricht University Medical Center+, Maastricht, The Netherlands
| | - Rodrigo Zacca
- Research Center in Physical Activity, Health and Leisure (CIAFEL), Faculty of Sports, University of Porto (FADEUP), Porto, Portugal,Laboratory for Integrative and Translational Research in Population Health (ITR), Porto, Portugal
| | - Márcio Fagundes Goethel
- Porto Biomechanics Laboratory (LABIOMEP-UP), University of Porto, Porto, Portugal,Centre of Research, Education, Innovation, and Intervention in Sport (CIFI2D), Faculty of Sports, University of Porto, Porto, Portugal
| | - David Bruce Pyne
- University of Canberra Research Institute for Sport and Exercise (UCRISE), University of Canberra, Canberra, Australia
| | - Brayden M Wood
- Exercise Physiology Laboratory, Department of Sports Medicine, Pepperdine University, Malibu, California
| | - Peyton E Allen
- Exercise Physiology Laboratory, Department of Sports Medicine, Pepperdine University, Malibu, California
| | - Jaden L Gabelhausen
- Exercise Physiology Laboratory, Department of Sports Medicine, Pepperdine University, Malibu, California
| | - Alexandra M Keller
- Exercise Physiology Laboratory, Department of Sports Medicine, Pepperdine University, Malibu, California
| | - Mast T Lige
- Exercise Physiology Laboratory, Department of Sports Medicine, Pepperdine University, Malibu, California
| | - Alicia S Oumsang
- Exercise Physiology Laboratory, Department of Sports Medicine, Pepperdine University, Malibu, California
| | - Greg L Smart
- Exercise Physiology Laboratory, Department of Sports Medicine, Pepperdine University, Malibu, California
| | - Hunter L Paris
- Exercise Physiology Laboratory, Department of Sports Medicine, Pepperdine University, Malibu, California
| | - Arthur H Dewolf
- Laboratory of Physiology and Biomechanics of Human Locomotion, Institute of Neuroscience, Université catholique de Louvain-la-Neuve, Louvain-la-Neuve, Belgium
| | - Guillaume Toffoli
- Department for Life Quality Studies, University of Bologna, Bologna, Italy
| | | | - Samuele M Marcora
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | | | - Ricardo J Fernandes
- Research Center in Physical Activity, Health and Leisure (CIAFEL), Faculty of Sports, University of Porto (FADEUP), Porto, Portugal,Porto Biomechanics Laboratory (LABIOMEP-UP), University of Porto, Porto, Portugal
| | - Susana M Soares
- Research Center in Physical Activity, Health and Leisure (CIAFEL), Faculty of Sports, University of Porto (FADEUP), Porto, Portugal,Porto Biomechanics Laboratory (LABIOMEP-UP), University of Porto, Porto, Portugal
| | - J. Arturo Abraldes
- Research Group MS&SPORT, Faculty of Sports Sciences, University of Murcia, Murcia, Spain
| | - Guilherme Matta
- Faculty of Science, Engineering and Social Sciences, School of Psychology and Life Sciences, Canterbury Christ Church University, Canterbury, United Kingdom
| | - Arthur Henrique Bossi
- MeFit Prehabilitation Service, Medway NHS Foundation Trust, Gillingham, United Kingdom
| | - D G McCarthy
- Department of Kinesiology, McMaster University, Hamilton, Ontario, Canada
| | - W Bostad
- Department of Kinesiology, McMaster University, Hamilton, Ontario, Canada
| | - J Gibala
- Department of Kinesiology, McMaster University, Hamilton, Ontario, Canada
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Takahashi K, Kitaoka Y, Hatta H. Effects of endurance training on metabolic enzyme activity and transporter protein levels in the skeletal muscles of orchiectomized mice. J Physiol Sci 2022; 72:14. [PMID: 35768774 PMCID: PMC10717707 DOI: 10.1186/s12576-022-00839-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2022] [Accepted: 06/18/2022] [Indexed: 12/20/2022]
Abstract
This study investigated whether endurance training attenuates orchiectomy (ORX)-induced metabolic alterations. At 7 days of recovery after sham operation or ORX surgery, the mice were randomized to remain sedentary or undergo 5 weeks of treadmill running training (15-20 m/min, 60 min, 5 days/week). ORX decreased glycogen concentration in the gastrocnemius muscle, enhanced phosphofructokinase activity in the plantaris muscle, and decreased lactate dehydrogenase activity in the plantaris and soleus muscles. Mitochondrial enzyme activities and protein content in the plantaris and soleus muscles were also decreased after ORX, but preserved, in part, by endurance training. In the treadmill running test (15 m/min, 60 min) after 4 weeks of training, orchiectomized sedentary mice showed impaired exercise performance, which was restored by endurance training. Thus, endurance training could be a potential therapeutic strategy to prevent the hypoandrogenism-induced decline in muscle mitochondrial content and physical performance.
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Affiliation(s)
- Kenya Takahashi
- Department of Sports Sciences, Graduate School of Arts and Sciences, The University of Tokyo, 3-8-1, Komaba, Meguro-ku, Tokyo, 153-8902, Japan.
| | - Yu Kitaoka
- Department of Human Sciences, Kanagawa University, 3-27-1, Rokkakubashi, Kanagawa-ku, Yokohama, Kanagawa, 221-8686, Japan
| | - Hideo Hatta
- Department of Sports Sciences, Graduate School of Arts and Sciences, The University of Tokyo, 3-8-1, Komaba, Meguro-ku, Tokyo, 153-8902, Japan
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28
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The Performance, Physiology and Morphology of Female and Male Olympic-Distance Triathletes. Healthcare (Basel) 2022; 10:healthcare10050797. [PMID: 35627934 PMCID: PMC9140916 DOI: 10.3390/healthcare10050797] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Revised: 04/12/2022] [Accepted: 04/21/2022] [Indexed: 11/25/2022] Open
Abstract
Sex differences in triathlon performance have been decreasing in recent decades and little information is available to explain it. Thirty-nine male and eighteen female amateur triathletes were evaluated for fat mass, lean mass, maximal oxygen uptake (VO2 max), ventilatory threshold (VT), respiratory compensation point (RCP), and performance in a national Olympic triathlon race. Female athletes presented higher fat mass (p = 0.02, d = 0.84, power = 0.78) and lower lean mass (p < 0.01, d = 3.11, power = 0.99). VO2 max (p < 0.01, d = 1.46, power = 0.99), maximal aerobic velocity (MAV) (p < 0.01, d = 2.05, power = 0.99), velocities in VT (p < 0.01, d = 1.26, power = 0.97), and RCP (p < 0.01, d = 1.53, power = 0.99) were significantly worse in the female group. VT (%VO2 max) (p = 0.012, d = 0.73, power = 0.58) and RCP (%VO2 max) (p = 0.005, d = 0.85, power = 0.89) were higher in the female group. Female athletes presented lower VO2 max value, lower lean mass, and higher fat mass. However, females presented higher values of aerobic endurance (%VO2 max), which can attenuate sex differences in triathlon performance. Coaches and athletes should consider that female athletes can maintain a higher percentage of MAV values than males during the running split to prescribe individual training.
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Szanto S, Mody T, Gyurcsik Z, Babjak LB, Somogyi V, Barath B, Varga A, Matrai AA, Nemeth N. Alterations of Selected Hemorheological and Metabolic Parameters Induced by Physical Activity in Untrained Men and Sportsmen. Metabolites 2021; 11:metabo11120870. [PMID: 34940627 PMCID: PMC8706578 DOI: 10.3390/metabo11120870] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2021] [Revised: 12/06/2021] [Accepted: 12/13/2021] [Indexed: 02/06/2023] Open
Abstract
Optimal tissue oxygen supply is essential for proper athletic performance and endurance. It also depends on perfusion, so on hemorheological properties and microcirculation. Regular exercise is beneficial to the rheological status, depending on its type, intensity, and duration. We aimed to investigate macro and microrheological changes due to short, high-intensity exercise in professional athletes (soccer and ice hockey players) and untrained individuals. The exercise was performed on a treadmill ergometer during a spiroergometry examination. Blood samples were taken before and after exercise to analyze lactate concentration, hematological parameters, blood and plasma viscosity, and red blood cell (RBC) deformability and aggregation. Leukocyte, RBC and platelet counts, and blood viscosity increased with exercise, by the largest magnitude in the untrained group. RBC deformability slightly impaired after exercise, but showed better values in ice hockey versus soccer players. RBC aggregation increased with exercise, dominantly in ice hockey players. Lactate increased mostly in soccer players, and the respiratory exchange rate was the lowest in ice hockey players. Overall, short, high-intensity exercise altered macro and microrheological parameters, mostly in the untrained group. Significant differences were found between the two sports. The data can be useful in training status monitoring, selection, and in revealing the causes of physical loading symptoms.
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Affiliation(s)
- Sandor Szanto
- Department of Sports Medicine, Faculty of Medicine, University of Debrecen, Nagyerdei Park 12, H-4032 Debrecen, Hungary; (S.S.); (T.M.); (Z.G.)
| | - Tobias Mody
- Department of Sports Medicine, Faculty of Medicine, University of Debrecen, Nagyerdei Park 12, H-4032 Debrecen, Hungary; (S.S.); (T.M.); (Z.G.)
- Doctoral School of Clinical Medicine, University of Debrecen, Nagyerdei krt. 98, H-4032 Debrecen, Hungary
| | - Zsuzsanna Gyurcsik
- Department of Sports Medicine, Faculty of Medicine, University of Debrecen, Nagyerdei Park 12, H-4032 Debrecen, Hungary; (S.S.); (T.M.); (Z.G.)
| | - Laszlo Balint Babjak
- Department of Operative Techniques and Surgical Research, Faculty of Medicine, University of Debrecen, Moricz Zsigmond u. 22, H-4002 Debrecen, Hungary; (L.B.B.); (V.S.); (B.B.); (A.V.); (A.A.M.)
| | - Viktoria Somogyi
- Department of Operative Techniques and Surgical Research, Faculty of Medicine, University of Debrecen, Moricz Zsigmond u. 22, H-4002 Debrecen, Hungary; (L.B.B.); (V.S.); (B.B.); (A.V.); (A.A.M.)
| | - Barbara Barath
- Department of Operative Techniques and Surgical Research, Faculty of Medicine, University of Debrecen, Moricz Zsigmond u. 22, H-4002 Debrecen, Hungary; (L.B.B.); (V.S.); (B.B.); (A.V.); (A.A.M.)
| | - Adam Varga
- Department of Operative Techniques and Surgical Research, Faculty of Medicine, University of Debrecen, Moricz Zsigmond u. 22, H-4002 Debrecen, Hungary; (L.B.B.); (V.S.); (B.B.); (A.V.); (A.A.M.)
| | - Adam Attila Matrai
- Department of Operative Techniques and Surgical Research, Faculty of Medicine, University of Debrecen, Moricz Zsigmond u. 22, H-4002 Debrecen, Hungary; (L.B.B.); (V.S.); (B.B.); (A.V.); (A.A.M.)
| | - Norbert Nemeth
- Department of Operative Techniques and Surgical Research, Faculty of Medicine, University of Debrecen, Moricz Zsigmond u. 22, H-4002 Debrecen, Hungary; (L.B.B.); (V.S.); (B.B.); (A.V.); (A.A.M.)
- Correspondence: ; Tel./Fax: +36-52-416-915
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30
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Leo P, Spragg J, Podlogar T, Lawley JS, Mujika I. Power profiling and the power-duration relationship in cycling: a narrative review. Eur J Appl Physiol 2021; 122:301-316. [PMID: 34708276 PMCID: PMC8783871 DOI: 10.1007/s00421-021-04833-y] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Accepted: 10/14/2021] [Indexed: 12/03/2022]
Abstract
Emerging trends in technological innovations, data analysis and practical applications have facilitated the measurement of cycling power output in the field, leading to improvements in training prescription, performance testing and race analysis. This review aimed to critically reflect on power profiling strategies in association with the power-duration relationship in cycling, to provide an updated view for applied researchers and practitioners. The authors elaborate on measuring power output followed by an outline of the methodological approaches to power profiling. Moreover, the deriving a power-duration relationship section presents existing concepts of power-duration models alongside exercise intensity domains. Combining laboratory and field testing discusses how traditional laboratory and field testing can be combined to inform and individualize the power profiling approach. Deriving the parameters of power-duration modelling suggests how these measures can be obtained from laboratory and field testing, including criteria for ensuring a high ecological validity (e.g. rider specialization, race demands). It is recommended that field testing should always be conducted in accordance with pre-established guidelines from the existing literature (e.g. set number of prediction trials, inter-trial recovery, road gradient and data analysis). It is also recommended to avoid single effort prediction trials, such as functional threshold power. Power-duration parameter estimates can be derived from the 2 parameter linear or non-linear critical power model: P(t) = W′/t + CP (W′—work capacity above CP; t—time). Structured field testing should be included to obtain an accurate fingerprint of a cyclist’s power profile.
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Affiliation(s)
- Peter Leo
- Division of Performance Physiology & Prevention, Department of Sport Science, University Innsbruck, Innsbruck, Austria.
| | - James Spragg
- Health Physical Activity Lifestyle Sport Research Centre (HPALS), University of Cape Town, Cape Town, South Africa
| | - Tim Podlogar
- Faculty of Health Sciences, University of Primorska, Izola, Slovenia
- Department of Automatics, Biocybernetics and Robotics, Jožef Stefan Institute, Ljubljana, Slovenia
| | - Justin S Lawley
- Division of Performance Physiology & Prevention, Department of Sport Science, University Innsbruck, Innsbruck, Austria
| | - Iñigo Mujika
- Department of Physiology, Faculty of Medicine and Nursing, University of the Basque Country, Leioa, Basque Country, Spain
- Exercise Science Laboratory, School of Kinesiology, Faculty of Medicine, Universidad Finis Terrae, Santiago, Chile
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The W' Balance Model: Mathematical and Methodological Considerations. Int J Sports Physiol Perform 2021; 16:1561-1572. [PMID: 34686611 DOI: 10.1123/ijspp.2021-0205] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Revised: 07/15/2021] [Accepted: 07/21/2021] [Indexed: 11/18/2022]
Abstract
Since its publication in 2012, the W' balance model has become an important tool in the scientific armamentarium for understanding and predicting human physiology and performance during high-intensity intermittent exercise. Indeed, publications featuring the model are accumulating, and it has been adapted for popular use both in desktop computer software and on wrist-worn devices. Despite the model's intuitive appeal, it has achieved mixed results thus far, in part due to a lack of clarity in its basis and calculation. Purpose: This review examines the theoretical basis, assumptions, calculation methods, and the strengths and limitations of the integral and differential forms of the W' balance model. In particular, the authors emphasize that the formulations are based on distinct assumptions about the depletion and reconstitution of W' during intermittent exercise; understanding the distinctions between the 2 forms will enable practitioners to correctly implement the models and interpret their results. The authors then discuss foundational issues affecting the validity and utility of the model, followed by evaluating potential modifications and suggesting avenues for further research. Conclusions: The W' balance model has served as a valuable conceptual and computational tool. Improved versions may better predict performance and further advance the physiology of high-intensity intermittent exercise.
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Caen K, Bourgois G, Dauwe C, Blancquaert L, Vermeire K, Lievens E, VAN Dorpe JO, Derave W, Bourgois JG, Pringels L, Boone J. W' Recovery Kinetics after Exhaustion: A Two-Phase Exponential Process Influenced by Aerobic Fitness. Med Sci Sports Exerc 2021; 53:1911-1921. [PMID: 33787532 DOI: 10.1249/mss.0000000000002673] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
PURPOSE The aims of this study were 1) to model the temporal profile of W' recovery after exhaustion, 2) to estimate the contribution of changing V˙O2 kinetics to this recovery, and 3) to examine associations with aerobic fitness and muscle fiber type (MFT) distribution. METHODS Twenty-one men (age = 25 ± 2 yr, V˙O2peak = 54.4 ± 5.3 mL·min-1·kg-1) performed several constant load tests to determine critical power and W' followed by eight trials to quantify W' recovery. Each test consisted of two identical exhaustive work bouts (WB1 and WB2), separated by a variable recovery interval of 30, 60, 120, 180, 240, 300, 600, or 900 s. Gas exchange was measured and muscle biopsies were collected to determine MFT distribution. W' recovery was quantified as observed W' recovery (W'OBS), model-predicted W' recovery (W'BAL), and W' recovery corrected for changing V˙O2 kinetics (W'ADJ). W'OBS and W'ADJ were modeled using mono- and biexponential fitting. Root-mean-square error (RMSE) and Akaike information criterion (∆AICC) were used to evaluate the models' accuracy. RESULTS The W'BAL model (τ = 524 ± 41 s) was associated with an RMSE of 18.6% in fitting W'OBS and underestimated W' recovery for all durations below 5 min (P < 0.002). Monoexponential modeling of W'OBS resulted in τ = 104 s with RMSE = 6.4%. Biexponential modeling of W'OBS resulted in τ1 = 11 s and τ2 = 256 s with RMSE = 1.7%. W'ADJ was 11% ± 1.5% lower than W'OBS (P < 0.001). ∆AICC scores favored the biexponential model for W'OBS, but not for W'ADJ. V˙O2peak (P = 0.009) but not MFT distribution (P = 0.303) was associated with W'OBS. CONCLUSION We showed that W' recovery from exhaustion follows a two-phase exponential time course that is dependent on aerobic fitness. The appearance of a fast initial recovery phase was attributed to an enhanced aerobic energy provision resulting from changes in V˙O2 kinetics.
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Affiliation(s)
| | - Gil Bourgois
- Department of Movement and Sports Sciences, Ghent University, Ghent, BELGIUM
| | - Charles Dauwe
- Department of Subatomic and Radiation Physics, Ghent University, Ghent, BELGIUM
| | - Laura Blancquaert
- Department of Movement and Sports Sciences, Ghent University, Ghent, BELGIUM
| | - Kobe Vermeire
- Department of Movement and Sports Sciences, Ghent University, Ghent, BELGIUM
| | - Eline Lievens
- Department of Movement and Sports Sciences, Ghent University, Ghent, BELGIUM
| | - J O VAN Dorpe
- Department of Pathology, Ghent University Hospital, Ghent, BELGIUM
| | - Wim Derave
- Department of Movement and Sports Sciences, Ghent University, Ghent, BELGIUM
| | | | - Lauren Pringels
- Department of Movement and Sports Sciences, Ghent University, Ghent, BELGIUM
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van der Zwaard S, Brocherie F, Jaspers RT. Under the Hood: Skeletal Muscle Determinants of Endurance Performance. Front Sports Act Living 2021; 3:719434. [PMID: 34423293 PMCID: PMC8371266 DOI: 10.3389/fspor.2021.719434] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Accepted: 07/05/2021] [Indexed: 11/21/2022] Open
Abstract
In the past decades, researchers have extensively studied (elite) athletes' physiological responses to understand how to maximize their endurance performance. In endurance sports, whole-body measurements such as the maximal oxygen consumption, lactate threshold, and efficiency/economy play a key role in performance. Although these determinants are known to interact, it has also been demonstrated that athletes rarely excel in all three. The leading question is how athletes reach exceptional values in one or all of these determinants to optimize their endurance performance, and how such performance can be explained by (combinations of) underlying physiological determinants. In this review, we advance on Joyner and Coyle's conceptual framework of endurance performance, by integrating a meta-analysis of the interrelationships, and corresponding effect sizes between endurance performance and its key physiological determinants at the macroscopic (whole-body) and the microscopic level (muscle tissue, i.e., muscle fiber oxidative capacity, oxygen supply, muscle fiber size, and fiber type). Moreover, we discuss how these physiological determinants can be improved by training and what potential physiological challenges endurance athletes may face when trying to maximize their performance. This review highlights that integrative assessment of skeletal muscle determinants points toward efficient type-I fibers with a high mitochondrial oxidative capacity and strongly encourages well-adjusted capillarization and myoglobin concentrations to accommodate the required oxygen flux during endurance performance, especially in large muscle fibers. Optimisation of endurance performance requires careful design of training interventions that fine tune modulation of exercise intensity, frequency and duration, and particularly periodisation with respect to the skeletal muscle determinants.
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Affiliation(s)
- Stephan van der Zwaard
- Department of Human Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, Amsterdam, Netherlands
- Laboratory for Myology, Department of Human Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, Amsterdam, Netherlands
- Leiden Institute of Advanced Computer Science, Leiden University, Leiden, Netherlands
| | - Franck Brocherie
- Laboratory Sport, Expertise and Performance (EA 7370), French Institute of Sport (INSEP), Paris, France
| | - Richard T. Jaspers
- Department of Human Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, Amsterdam, Netherlands
- Laboratory for Myology, Department of Human Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, Amsterdam, Netherlands
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Jacques M, Landen S, Alvarez Romero J, Yan X, Garnham A, Hiam D, Siegwald M, Mercier E, Hecksteden A, Eynon N, Voisin S. Individual physiological and mitochondrial responses during 12 weeks of intensified exercise. Physiol Rep 2021; 9:e14962. [PMID: 34327858 PMCID: PMC8322753 DOI: 10.14814/phy2.14962] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Accepted: 06/17/2021] [Indexed: 12/02/2022] Open
Abstract
AIM Observed effects of exercise are highly variable between individuals, and subject-by-training interaction (i.e., individual response variability) is often not estimated. Here, we measured mitochondrial (citrate synthetase, cytochrome-c oxidase, succinate dehydrogenase, and mitochondrial copy-number), performance markers (Wpeak , lactate threshold [LT], and VO2peak ), and fiber type proportions/expression (type I, type IIa, and type IIx) in multiple time points during 12-week of high-intensity interval training (HIIT) to investigate effects of exercise at the individual level. METHODS Sixteen young (age: 33.1 ± 9.0 years), healthy men (VO2peak 35-60 ml/min/kg and BMI: 26.4 ± 4.2) from the Gene SMART study completed 12-week of progressive HIIT. Performance markers and muscle biopsies were collected every 4 weeks. We used mixed-models and bivariate growth models to quantify individual response and to estimate correlations between variables. RESULTS All performance markers exhibited significant (Wpeak 0.56 ± 0.33 p = 0.003, LT 0.37 ± 0.35 p = 0.007, VO2peak 3.81 ± 6.13 p = 0.02) increases overtime, with subject-by-training interaction being present (95% CI: Wpeak 0.09-0.24, LT 0.06-0.18, VO2peak 0.27-2.32). All other measurements did not exhibit significant changes. Fiber type IIa proportions at baseline was significantly associated with all physiological variables (p < 0.05), and citrate synthetase and cytochrome-c oxidase levels at baseline and overtime (i.e., intercept and slope) presented significant covariance (p < 0.05). Finally, low correlations between performance and mitochondrial markers were observed. CONCLUSION We identified a significant subject-by-training interaction for the performance markers. While for all other measures within-subject variability was too large and interindividual differences in training efficacy could not be verified. Changes in measurements in response to exercise were not correlated, and such disconnection should be further investigated by future studies.
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Affiliation(s)
- Macsue Jacques
- Institute for Health and Sport (iHeS)Victoria UniversityMelbourneAustralia
| | - Shanie Landen
- Institute for Health and Sport (iHeS)Victoria UniversityMelbourneAustralia
| | | | - Xu Yan
- Institute for Health and Sport (iHeS)Victoria UniversityMelbourneAustralia
- Australian Institute for Musculoskeletal Science (AIMSS)MelbourneAustralia
| | - Andrew Garnham
- Institute for Health and Sport (iHeS)Victoria UniversityMelbourneAustralia
| | - Danielle Hiam
- Institute for Health and Sport (iHeS)Victoria UniversityMelbourneAustralia
| | | | | | - Anne Hecksteden
- Institute of Sports and Preventive MedicineSaarland UniversitySaarbrückenGermany
| | - Nir Eynon
- Institute for Health and Sport (iHeS)Victoria UniversityMelbourneAustralia
- Murdoch Children’s Research InstituteMelbourneAustralia
| | - Sarah Voisin
- Institute for Health and Sport (iHeS)Victoria UniversityMelbourneAustralia
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Smyth B, Muniz-Pumares D. Calculation of Critical Speed from Raw Training Data in Recreational Marathon Runners. Med Sci Sports Exerc 2021; 52:2637-2645. [PMID: 32472926 PMCID: PMC7664951 DOI: 10.1249/mss.0000000000002412] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
INTRODUCTION Critical speed (CS) represents the highest intensity at which a physiological steady state may be reached. The aim of this study was to evaluate whether estimations of CS obtained from raw training data can predict performance and pacing in marathons. METHODS We investigated running activities logged into an online fitness platform by >25,000 recreational athletes before big-city marathons. Each activity contained time, distance, and elevation every 100 m. We computed grade-adjusted pacing and the fastest pace recorded for a set of target distances (400, 800, 1000, 1500, 3000, and 5000 m). CS was determined as the slope of the distance-time relationship using all combinations of, at least, three target distances. RESULTS The relationship between distance and time was linear, irrespective of the target distances used (pooled mean ± SD: R = 0.9999 ± 0.0001). The estimated values of CS from all models were not different (3.74 ± 0.08 m·s), and all models correlated with marathon performance (R = 0.672 ± 0.036, error = 8.01% ± 0.51%). CS from the model including 400, 800, and 5000 m best predicted performance (R = 0.695, error = 7.67%) and was used in further analysis. Runners completed the marathon at 84.8% ± 13.6% CS, with faster runners competing at speeds closer to CS (93.0% CS for 150 min marathon times vs 78.9% CS for 360 min marathon times). Runners who completed the first half of the marathon at >94% of their CS, and particularly faster than CS, were more likely to slowdown by more than 25% in the second half of race. CONCLUSION This study suggests that estimations of CS from raw training data can successfully predict marathon performance and provide useful pacing information.
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Affiliation(s)
- Barry Smyth
- Insight Centre for Data Analytics, School of Computer Science, University College Dublin, Dublin, IRELAND
| | - Daniel Muniz-Pumares
- School of Life and Medical Sciences, University of Hertfordshire, Hatfield, UNITED KINGDOM
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Pethick J, Winter SL, Burnley M. Physiological Evidence That the Critical Torque Is a Phase Transition, Not a Threshold. Med Sci Sports Exerc 2021; 52:2390-2401. [PMID: 32366801 PMCID: PMC7556242 DOI: 10.1249/mss.0000000000002389] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Introduction Distinct physiological responses to exercise occur in the heavy- and severe-intensity domains, which are separated by the critical power or critical torque (CT). However, how the transition between these intensity domains actually occurs is not known. We tested the hypothesis that CT is a sudden threshold, with no gradual transition from heavy- to severe-intensity behavior within the confidence limits associated with the CT. Methods Twelve healthy participants performed four exhaustive severe-intensity trials for the determination of CT, and four 30-min trials in close proximity to CT (one or two SE above or below each participant’s CT estimate; CT − 2, CT − 1, CT + 1, CT + 2). Muscle O2 uptake, rectified electromyogram, and torque variability and complexity were monitored throughout each trial, and maximal voluntary contractions (MVC) with femoral nerve stimulation were performed before and after each trial to determine central and peripheral fatigue responses. Results The rates of change in fatigue-related variables, muscle O2 uptake, electromyogram amplitude, and torque complexity were significantly faster in the severe trials compared with CT − 2. For example, the fall in MVC torque was −1.5 ± 0.8 N·m·min−1 in CT − 2 versus –7.9 ± 2.5 N·m·min−1 in the lowest severe-intensity trial (P < 0.05). Individual analyses showed a low frequency of severe responses even in the circa-CT trials ostensibly above the CT, but also the rare appearance of severe-intensity responses in all circa-CT trials. Conclusions These data demonstrate that the transition between heavy- and severe-intensity exercise occurs gradually rather than suddenly.
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Affiliation(s)
- Jamie Pethick
- Endurance Research Group, School of Sport and Exercise Sciences, University of Kent, Kent, UNITED KINGDOM
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The Relationship Between Neuromuscular Function and the W' in Elite Cyclists. Int J Sports Physiol Perform 2021; 16:1656-1662. [PMID: 33873151 DOI: 10.1123/ijspp.2020-0861] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Revised: 12/18/2020] [Accepted: 01/11/2021] [Indexed: 11/18/2022]
Abstract
PURPOSE To assess the association between the W' and measures of neuromuscular function relating to the capacity of skeletal muscle to produce force in a group of elite cyclists. METHODS Twenty-two athletes specializing in a range of disciplines and competing internationally volunteered to participate. Athletes completed assessments of maximum voluntary torque (MVT), voluntary activation, and isometric maximum voluntary contraction to measure rate of torque development (RTD). This was followed by assessment of peak power output (PPO) and 3-, 5-, and 12-minute time trials to determine critical power. Pearson correlation was used to examine associations with critical power and W'. Goodness of fit was calculated, and significant relationships were included in a linear stepwise regression model. RESULTS Significant positive relationships were evident between W' and MVT (r = .82), PPO (r = .70), and RTD at 200 milliseconds (r = .59) but not with RTD at 50 milliseconds and voluntary activation. Correlations were also observed between critical power and RTD at 200 milliseconds and MVT (r = .54 and r = .51, respectively) but not with PPO, voluntary activation, or RTD at 50 milliseconds. The regression analysis found that 87% of the variability in W' (F1,18 = 68.75; P < .001) was explained by 2 variables: MVT (81%) and PPO (6%). CONCLUSIONS It is likely that muscle size and strength, as opposed to neural factors, contribute meaningfully to W'. These data can be used to establish training methods to enhance W' to improve cycling performance in well-trained athletes.
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Ferguson RA, Mitchell EA, Taylor CW, Bishop DJ, Christiansen D. Blood-flow-restricted exercise: Strategies for enhancing muscle adaptation and performance in the endurance-trained athlete. Exp Physiol 2021; 106:837-860. [PMID: 33486814 DOI: 10.1113/ep089280] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2020] [Accepted: 01/19/2021] [Indexed: 12/15/2022]
Abstract
NEW FINDINGS What is the topic of this review? Blood-flow-restricted (BFR) exercise represents a potential approach to augment the adaptive response to training and improve performance in endurance-trained individuals. What advances does it highlight? When combined with low-load resistance exercise, low- and moderate-intensity endurance exercise and sprint interval exercise, BFR can provide an augmented acute stimulus for angiogenesis and mitochondrial biogenesis. These augmented acute responses can translate into enhanced capillary supply and mitochondrial function, and subsequent endurance-type performance, although this might depend on the nature of the exercise stimulus. There is a requirement to clarify whether BFR training interventions can be used by high-performance endurance athletes within their structured training programme. ABSTRACT A key objective of the training programme for an endurance athlete is to optimize the underlying physiological determinants of performance. Training-induced adaptations are governed by physiological and metabolic stressors, which initiate transcriptional and translational signalling cascades to increase the abundance and/or function of proteins to improve physiological function. One important consideration is that training adaptations are reduced as training status increases, which is reflected at the molecular level as a blunting of the acute signalling response to exercise. This review examines blood-flow-restricted (BFR) exercise as a strategy for augmenting exercise-induced stressors and subsequent molecular signalling responses to enhance the physiological characteristics of the endurance athlete. Focus is placed on the processes of capillary growth and mitochondrial biogenesis. Recent evidence supports that BFR exercise presents an intensified training stimulus beyond that of performing the same exercise alone. We suggest that this has the potential to induce enhanced physiological adaptations, including increases in capillary supply and mitochondrial function, which can contribute to an improvement in performance of endurance exercise. There is, however, a lack of consensus regarding the potency of BFR training, which is invariably attributable to the different modes, intensities and durations of exercise and BFR methods. Further studies are needed to confirm its potential in the endurance-trained athlete.
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Affiliation(s)
- Richard A Ferguson
- School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, UK
| | - Emma A Mitchell
- School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, UK
| | - Conor W Taylor
- Ineos Grenadiers Cycling Team, Bollin House, Wilmslow, UK
| | - David J Bishop
- Institute for Health and Sport (iHeS), Victoria University, Melbourne, Victoria, Australia
| | - Danny Christiansen
- Department of Internal Medicine, University of Utah, Salt Lake City, Utah, USA
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Goulding RP, Roche DM, Marwood S. Effect of Hyperoxia on Critical Power and V˙O2 Kinetics during Upright Cycling. Med Sci Sports Exerc 2020; 52:1041-1049. [PMID: 31815830 DOI: 10.1249/mss.0000000000002234] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
INTRODUCTION/PURPOSE Critical power (CP) is a fundamental parameter defining high-intensity exercise tolerance; however, its physiological determinants are incompletely understood. The present study determined the impact of hyperoxia on CP, the time constant of phase II pulmonary oxygen uptake kinetics (τV˙O2), and muscle oxygenation (assessed by near-infrared spectroscopy) in nine healthy men performing upright cycle ergometry. METHODS Critical power was determined in normoxia and hyperoxia (fraction of inspired O2 = 0.5) via four severe-intensity constant load exercise tests to exhaustion on a cycle ergometer, repeated once in each condition. During each test, τV˙O2 and the time constant of muscle deoxyhemoglobin kinetics (τ[HHb]), alongside absolute concentrations of muscle oxyhemoglobin ([HbO2]), were determined. RESULTS Critical power was greater (hyperoxia, 216 ± 30 W vs normoxia, 197 ± 29 W; P < 0.001), whereas W' was reduced (hyperoxia, 15.4 ± 5.2 kJ; normoxia, 17.5 ± 4.3 W; P = 0.037) in hyperoxia compared with normoxia. τV˙O2 (hyperoxia, 35 ± 12 s vs normoxia, 33 ± 10 s; P = 0.33) and τ[HHb] (hyperoxia, 11 ± 5 s vs normoxia, 14 ± 5 s; P = 0.65) were unchanged between conditions, whereas [HbO2] during exercise was greater in hyperoxia compared with normoxia (hyperoxia, 73 ± 20 vs normoxia, 66 ± 15 μM; P < 0.001). CONCLUSIONS This study provides novel insights into the physiological determinants of CP and by extension, exercise tolerance. Microvascular oxygenation and CP were improved during exercise in hyperoxia compared with normoxia. Importantly, the improved microvascular oxygenation afforded by hyperoxia did not alter τV˙O2, suggesting that microvascular O2 availability is an independent determinant of the upper limit for steady-state exercise, that is, CP.
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Affiliation(s)
- Richie P Goulding
- School of Health Sciences, Liverpool Hope University, Liverpool, UNITED KINGDOM
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Jones AM, Kirby BS, Clark IE, Rice HM, Fulkerson E, Wylie LJ, Wilkerson DP, Vanhatalo A, Wilkins BW. Physiological demands of running at 2-hour marathon race pace. J Appl Physiol (1985) 2020; 130:369-379. [PMID: 33151776 DOI: 10.1152/japplphysiol.00647.2020] [Citation(s) in RCA: 80] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The requirements of running a 2-h marathon have been extensively debated but the actual physiological demands of running at ∼21.1 km/h have never been reported. We therefore conducted laboratory-based physiological evaluations and measured running economy (O2 cost) while running outdoors at ∼21.1 km/h, in world-class distance runners as part of Nike's "Breaking 2" marathon project. On separate days, 16 world-class male distance runners (age, 29 ± 4 yr; height, 1.72 ± 0.04 m; mass, 58.9 ± 3.3 kg) completed an incremental treadmill test for the assessment of V̇O2peak, O2 cost of submaximal running, lactate threshold and lactate turn-point, and a track test during which they ran continuously at 21.1 km/h. The laboratory-determined V̇O2peak was 71.0 ± 5.7 mL/kg/min with lactate threshold and lactate turn-point occurring at 18.9 ± 0.4 and 20.2 ± 0.6 km/h, corresponding to 83 ± 5% and 92 ± 3% V̇O2peak, respectively. Seven athletes were able to attain a steady-state V̇O2 when running outdoors at 21.1 km/h. The mean O2 cost for these athletes was 191 ± 19 mL/kg/km such that running at 21.1 km/h required an absolute V̇O2 of ∼4.0 L/min and represented 94 ± 3% V̇O2peak. We report novel data on the O2 cost of running outdoors at 21.1 km/h, which enables better modeling of possible marathon performances by elite athletes. Using the value for O2 cost measured in this study, a sub 2-h marathon would require a 59 kg runner to sustain a V̇O2 of approximately 4.0 L/min or 67 mL/kg/min.NEW & NOTEWORTHY We report the physiological characteristics and O2 cost of running overground at ∼21.1 km/h in a cohort of the world's best male distance runners. We provide new information on the absolute and relative O2 uptake required to run at 2-h marathon pace.
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Affiliation(s)
- Andrew M Jones
- Sport and Health Sciences, College of Life and Environmental Sciences, St. Luke's Campus, University of Exeter, Exeter, United Kingdom
| | | | - Ida E Clark
- Sport and Health Sciences, College of Life and Environmental Sciences, St. Luke's Campus, University of Exeter, Exeter, United Kingdom
| | - Hannah M Rice
- Sport and Health Sciences, College of Life and Environmental Sciences, St. Luke's Campus, University of Exeter, Exeter, United Kingdom
| | | | - Lee J Wylie
- Sport and Health Sciences, College of Life and Environmental Sciences, St. Luke's Campus, University of Exeter, Exeter, United Kingdom
| | - Daryl P Wilkerson
- Sport and Health Sciences, College of Life and Environmental Sciences, St. Luke's Campus, University of Exeter, Exeter, United Kingdom
| | - Anni Vanhatalo
- Sport and Health Sciences, College of Life and Environmental Sciences, St. Luke's Campus, University of Exeter, Exeter, United Kingdom
| | - Brad W Wilkins
- Nike Sport Research Lab, Beaverton, Oregon.,Department of Human Physiology, Gonzaga University, Spokane, Washington
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Ansdell P, Thomas K, Hicks KM, Hunter SK, Howatson G, Goodall S. Physiological sex differences affect the integrative response to exercise: acute and chronic implications. Exp Physiol 2020; 105:2007-2021. [PMID: 33002256 DOI: 10.1113/ep088548] [Citation(s) in RCA: 143] [Impact Index Per Article: 35.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 09/24/2020] [Accepted: 09/28/2020] [Indexed: 12/13/2022]
Abstract
NEW FINDINGS What is the topic of this review? We review sex differences within physiological systems implicated in exercise performance; specifically, how they integrate to determine metabolic thresholds and fatigability. Thereafter, we discuss the implications that these sex differences might have for long-term adaptation to exercise. What advances does it highlight? The review collates evidence from recent physiological studies that have investigated sex as a biological variable, demonstrating that the physiological response to equivalent 'dosages' of exercise is not the same in males and females; thus, highlighting the need to research diversity in physiological responses to interventions. ABSTRACT The anatomical and physiological differences between males and females are thought to determine differences in the limits of human performance. The notion of studying sex as a biological variable has recently been emphasized in the biosciences as a vital step in enhancing human health. In this review, we contend that the effects of biological sex on acute and chronic responses must be studied and accounted for when prescribing aerobic exercise, much like any intervention targeting the optimization of physiological function. Emerging evidence suggests that the response of physiological systems to exercise differs between males and females, potentially mediating the beneficial effects in healthy and clinical populations. We highlight evidence that integrative metabolic thresholds during exercise are influenced by phenotypical sex differences throughout many physiological systems. Furthermore, we discuss evidence that female skeletal muscle is more resistant to fatigue elicited by equivalent dosages of high-intensity exercise. How the different acute responses affect the long-term trainability of males and females is considered, with discussion about tailoring exercise to the characteristics of the individual presented within the context of biological sex. Finally, we highlight the influence of endogenous and exogenous sex hormones on physiological responses to exercise in females. Sex is one of many mediating influences on the outcomes of exercise, and with careful experimental designs, physiologists can advance the collective understanding of diversity in physiology and optimize outcomes for both sexes.
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Affiliation(s)
- Paul Ansdell
- Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne, UK
| | - Kevin Thomas
- Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne, UK
| | - Kirsty M Hicks
- Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne, UK
| | - Sandra K Hunter
- Department of Physical Therapy, Marquette University, Milwaukee, WI, USA
| | - Glyn Howatson
- Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne, UK.,Water Research Group, School of Environmental Sciences and Development, North-West University, Potchefstroom, South Africa
| | - Stuart Goodall
- Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne, UK
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Ansdell P, Škarabot J, Atkinson E, Corden S, Tygart A, Hicks KM, Thomas K, Hunter SK, Howatson G, Goodall S. Sex differences in fatigability following exercise normalised to the power-duration relationship. J Physiol 2020; 598:5717-5737. [PMID: 32964441 DOI: 10.1113/jp280031] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Accepted: 09/07/2020] [Indexed: 01/24/2023] Open
Abstract
KEY POINTS Knee-extensors demonstrate greater fatigue resistance in females compared to males during single-limb and whole-body exercise. For single-limb exercise, the intensity-duration relationship is different between sexes, with females sustaining a greater relative intensity of exercise. This study established the power-duration relationship during cycling, then assessed fatigability during critical power-matched exercise within the heavy and severe intensity domains. When critical power and the curvature constant were expressed relative to maximal ramp test power, no sex difference was observed. No sex difference in time to task failure was observed in either trial. During heavy and severe intensity cycling, females experienced lesser muscle de-oxygenation. Following both trials, females experienced lesser reductions in knee-extensor contractile function, and following heavy intensity exercise, females experienced less reduction in voluntary activation. These data demonstrate that whilst the relative power-duration relationship is not different between males and females, the mechanisms of fatigability during critical power-matched exercise are mediated by sex. ABSTRACT Due to morphological differences, females demonstrate greater fatigue resistance of locomotor muscle during single-limb and whole-body exercise modalities. Whilst females sustain a greater relative intensity of single-limb, isometric exercise than males, limited investigation has been performed during whole-body exercise. Accordingly, this study established the power-duration relationship during cycling in 18 trained participants (eight females). Subsequently, constant-load exercise was performed at critical power (CP)-matched intensities within the heavy and severe domains, with the mechanisms of fatigability assessed via non-invasive neurostimulation, near-infrared spectroscopy and pulmonary gas exchange during and following exercise. Relative CP (72 ± 5 vs. 74 ± 2% Pmax , P = 0.210) and curvature constant (51 ± 11 vs. 52 ± 10 J Pmax -1 , P = 0.733) of the power-duration relationship were similar between males and females. Subsequent heavy (P = 0.758) and severe intensity (P = 0.645) exercise time to task failures were not different between sexes. However, females experienced lesser reductions in contractile function at task failure (P ≤ 0.020), and greater vastus lateralis oxygenation (P ≤ 0.039) during both trials. Reductions in voluntary activation occurred following both trials (P < 0.001), but were less in females following the heavy trial (P = 0.036). Furthermore, during the heavy intensity trial only, corticospinal excitability was reduced at the cortical (P = 0.020) and spinal (P = 0.036) levels, but these reductions were not sex-dependent. Other than a lower respiratory exchange ratio in the heavy trial for females (P = 0.039), no gas exchange variables differed between sexes (P ≥ 0.052). Collectively, these data demonstrate that whilst the relative power-duration relationship is not different between males and females, the mechanisms of fatigability during CP-matched exercise above and below CP are mediated by sex.
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Affiliation(s)
- Paul Ansdell
- Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne, UK
| | - Jakob Škarabot
- Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne, UK.,School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, UK
| | - Elliott Atkinson
- Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne, UK
| | - Sarah Corden
- Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne, UK
| | - Amber Tygart
- Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne, UK
| | - Kirsty M Hicks
- Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne, UK
| | - Kevin Thomas
- Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne, UK
| | - Sandra K Hunter
- Department of Physical Therapy, Marquette University, Milwaukee, WI, USA
| | - Glyn Howatson
- Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne, UK.,Water Research Group, School of Environmental Sciences and Development, North-West University, Potchefstroom, South Africa
| | - Stuart Goodall
- Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne, UK
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The Application of Critical Power, the Work Capacity above Critical Power (W'), and its Reconstitution: A Narrative Review of Current Evidence and Implications for Cycling Training Prescription. Sports (Basel) 2020; 8:sports8090123. [PMID: 32899777 PMCID: PMC7552657 DOI: 10.3390/sports8090123] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 08/28/2020] [Accepted: 09/02/2020] [Indexed: 12/17/2022] Open
Abstract
The two-parameter critical power (CP) model is a robust mathematical interpretation of the power–duration relationship, with CP being the rate associated with the maximal aerobic steady state, and W′ the fixed amount of tolerable work above CP available without any recovery. The aim of this narrative review is to describe the CP concept and the methodologies used to assess it, and to summarize the research applying it to intermittent cycle training techniques. CP and W′ are traditionally assessed using a number of constant work rate cycling tests spread over several days. Alternatively, both the 3-min all-out and ramp all-out protocols provide valid measurements of CP and W′ from a single test, thereby enhancing their suitability to athletes and likely reducing errors associated with the assumptions of the CP model. As CP represents the physiological landmark that is the boundary between heavy and severe intensity domains, it presents several advantages over the de facto arbitrarily defined functional threshold power as the basis for cycle training prescription at intensities up to CP. For intensities above CP, precise prescription is not possible based solely on aerobic measures; however, the addition of the W′ parameter does facilitate the prescription of individualized training intensities and durations within the severe intensity domain. Modelling of W′ reconstitution extends this application, although more research is needed to identify the individual parameters that govern W′ reconstitution rates and their kinetics.
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44
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Chorley A, Bott RP, Marwood S, Lamb KL. Physiological and anthropometric determinants of critical power, W' and the reconstitution of W' in trained and untrained male cyclists. Eur J Appl Physiol 2020; 120:2349-2359. [PMID: 32776219 PMCID: PMC7560916 DOI: 10.1007/s00421-020-04459-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2020] [Accepted: 07/31/2020] [Indexed: 11/26/2022]
Abstract
Purpose This study examined the relationship of physiological and anthropometric characteristics with parameters of the critical power (CP) model, and in particular the reconstitution of W′ following successive bouts of maximal exercise, amongst trained and untrained cyclists. Methods Twenty male adults (trained nine; untrained 11; age 39 ± 15 year; mass 74.7 ± 8.7 kg; V̇O2max 58.0 ± 8.7 mL kg−1 min−1) completed three incremental ramps (20 W min−1) to exhaustion interspersed with 2-min recoveries. Pearson’s correlation coefficients were used to assess relationships for W′ reconstitution after the first recovery (W′rec1), the delta in W′ reconstituted between recoveries (∆W′rec), CP and W′. Results CP was strongly related to V̇O2max for both trained (r = 0.82) and untrained participants (r = 0.71), whereas W′ was related to V̇O2max when both groups were considered together (r = 0.54). W′rec1 was strongly related to V̇O2max for the trained (r = 0.81) but not untrained (r = 0.18); similarly, ∆W′rec was strongly related to V̇O2max (r = − 0.85) and CP (r = − 0.71) in the trained group only. Conclusions Notable physiological relationships between parameters of aerobic fitness and the measurements of W′ reconstitution were observed, which differed among groups. The amount of W′ reconstitution and the maintenance of W′ reconstitution that occurred with repeated bouts of maximal exercise were found to be related to key measures of aerobic fitness such as CP and V̇O2max. This data demonstrates that trained cyclists wishing to improve their rate of W′ reconstitution following repeated efforts should focus training on improving key aspects of aerobic fitness such as V̇O2max and CP.
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Affiliation(s)
- Alan Chorley
- Department of Sport and Exercise Sciences, University of Chester, Chester, CH1 4BJ, UK.
| | - Richard P Bott
- Department of Sport and Exercise Sciences, University of Chester, Chester, CH1 4BJ, UK
| | - Simon Marwood
- School of Health Sciences, Liverpool Hope University, Liverpool, L16 9JD, UK
| | - Kevin L Lamb
- Department of Sport and Exercise Sciences, University of Chester, Chester, CH1 4BJ, UK
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45
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Zubac D, Ivančev V, Valić Z, Šimunič B. Long-lasting exercise involvement protects against decline in V̇O 2max and V̇O 2 kinetics in moderately active women. Appl Physiol Nutr Metab 2020; 46:108-116. [PMID: 32640173 DOI: 10.1139/apnm-2020-0307] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
We studied the effects of age on different physiological parameters, including those derived from (i) maximal cardiopulmonary exercise testing (CPET), (ii) moderate-intensity step transitions, and (iii) tensiomyography (TMG)-derived variables in moderately active women. Twenty-eight women (age, 19 to 53 years), completed 3 laboratory visits, including baseline data collection, TMG assessment, maximal oxygen uptake test via CPET, and a step-transition test from 20 W to a moderate-intensity cycling power output (PO), corresponding to oxygen uptake at 90% gas exchange threshold. During the step transitions, breath-by-breath pulmonary oxygen uptake, near infrared spectroscopy derived muscle deoxygenation (ΔHHb), and beat-by-beat cardiovascular response were continuously monitored. There were no differences observed between the young and middle-aged women in their maximal oxygen uptake and peak PO, while the maximal heart rate (HR) was 12 bpm lower in middle-aged compared with young (p = 0.016) women. Also, no differences were observed between the age groups in τ pulmonary oxygen uptake, ΔHHb, and τHR during on-transients. The first regression model showed that age did not attenuate the maximal CPET capacity in the studied population (p = 0.638), while in the second model a faster τ pulmonary oxygen uptake, combined with shorter TMG-derived contraction time (Tc) of the vastus lateralis (VL), were associated with a higher maximal oxygen uptake (∼30% of explained variance, p = 0.039). In conclusion, long lasting exercise involvement protects against a maximal oxygen uptake and τpulmonary oxygen uptake deterioration in moderately active women. Novelty: Faster τ pulmonary oxygen uptake and shorter Tc of the VL explain 33% of the variance in superior maximal oxygen uptake attainment. No differences between age groups were found in τ pulmonary oxygen uptake, τΔHHb, and τHR during on-transients.
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Affiliation(s)
- Damir Zubac
- Institute for Kinesiology Research, Science and Research Center of Koper, Koper, Slovenia.,Faculty of Kinesiology, University of Split, Split, Croatia
| | | | - Zoran Valić
- Department of Integrative Physiology, University of Split, School of Medicine, Split, Croatia
| | - Boštjan Šimunič
- Institute for Kinesiology Research, Science and Research Center of Koper, Koper, Slovenia
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46
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Ansdell P, Brownstein CG, Škarabot J, Hicks KM, Howatson G, Thomas K, Hunter SK, Goodall S. Sex differences in fatigability and recovery relative to the intensity-duration relationship. J Physiol 2019; 597:5577-5595. [PMID: 31529693 DOI: 10.1113/jp278699] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Accepted: 09/12/2019] [Indexed: 12/15/2022] Open
Abstract
KEY POINTS Females demonstrate greater fatigue resistance than males during contractions at intensities relative to maximum force. However, previous studies have not accounted for the influence of metabolic thresholds on fatigability. This study is the first to test whether sex differences in fatigability exist when exercise intensity is normalised relative to a metabolic threshold: the critical intensity derived from assessment of the intensity-duration relationship during intermittent, isometric knee extensor contractions. We show that critical intensity in females occurred at a higher percentage of maximum force compared to males. Furthermore, females demonstrated greater fatigue resistance at exercise intensities above and below this metabolic threshold. Our data suggest that the sex difference was mediated by lesser deoxygenation of the knee extensors during exercise. These data highlight the importance of accounting for metabolic thresholds when comparing fatigability between sexes, whilst emphasising the notion that male data are not generalisable to female populations. ABSTRACT Females are less fatigable than males during isometric exercise at intensities relative to maximal voluntary contraction (MVC); however, whether a sex difference in fatigability exists when exercise is prescribed relative to a critical intensity is unknown. This study established the intensity-duration relationship, and compared fatigability and recovery between sexes following intermittent isometric contractions normalised to critical intensity. Twenty participants (10 females) completed four intermittent isometric knee extension trials to task failure to determine critical intensity and the curvature constant (W'), followed by fatiguing tasks at +10% and -10% relative to critical intensity. Neuromuscular assessments were completed at baseline and for 45 min post-exercise. Non-invasive neurostimulation, near-infrared spectroscopy, and non-invasive haemodynamic monitoring were used to elucidate the physiological mechanisms responsible for sex differences. Females demonstrated a greater critical intensity relative to MVC than males (25 ± 3 vs. 21 ± 2% MVC, P = 0.003), with no sex difference for W' (18,206 ± 6331 vs. 18,756 ± 5762 N s, P = 0.850). Time to task failure was greater for females (62.37 ± 17.25 vs. 30.43 ± 12.75 min, P < 0.001) during the +10% trial, and contractile function recovered faster post-exercise (P = 0.034). During the -10% trial females experienced less contractile dysfunction (P = 0.011). Throughout the +10% trial, females demonstrated lesser decreases in deoxyhaemoglobin (P = 0.007) and an attenuated exercise pressor reflex. These data show that a sex difference in fatigability exists even when exercise is matched for critical intensity. We propose that greater oxygen availability during exercise permits females to sustain a higher relative intensity than males, and is an explanatory factor for the sex difference in fatigability during intermittent, isometric contractions.
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Affiliation(s)
- Paul Ansdell
- Faculty of Health and Life Sciences, Northumbria University, Newcastle Upon Tyne, UK
| | - Callum G Brownstein
- Faculty of Health and Life Sciences, Northumbria University, Newcastle Upon Tyne, UK.,Université Lyon, UJM-Saint-Etienne, Inter-university Laboratory of Human Movement Biology, Saint-Etienne, France
| | - Jakob Škarabot
- Faculty of Health and Life Sciences, Northumbria University, Newcastle Upon Tyne, UK
| | - Kirsty M Hicks
- Faculty of Health and Life Sciences, Northumbria University, Newcastle Upon Tyne, UK
| | - Glyn Howatson
- Faculty of Health and Life Sciences, Northumbria University, Newcastle Upon Tyne, UK.,Water Research Group, School of Environmental Sciences and Development, Northwest University, Potchefstroom, South Africa
| | - Kevin Thomas
- Faculty of Health and Life Sciences, Northumbria University, Newcastle Upon Tyne, UK
| | - Sandra K Hunter
- Department of Physical Therapy, Marquette University, Milwaukee, WI, USA
| | - Stuart Goodall
- Faculty of Health and Life Sciences, Northumbria University, Newcastle Upon Tyne, UK
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47
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Iannetta D, Passfield L, Qahtani A, MacInnis MJ, Murias JM. Interlimb differences in parameters of aerobic function and local profiles of deoxygenation during double-leg and counterweighted single-leg cycling. Am J Physiol Regul Integr Comp Physiol 2019; 317:R840-R851. [PMID: 31617749 DOI: 10.1152/ajpregu.00164.2019] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
It is typically assumed that in the context of double-leg cycling, dominant (DOMLEG) and nondominant legs (NDOMLEG) have similar aerobic capacity and both contribute equally to the whole body physiological responses. However, there is a paucity of studies that have systematically investigated maximal and submaximal aerobic performance and characterized the profiles of local muscle deoxygenation in relation to leg dominance. Using counterweighted single-leg cycling, this study explored whether peak O2 consumption (V̇o2peak), maximal lactate steady-state (MLSSp), and profiles of local deoxygenation [HHb] would be different in the DOMLEG compared with the NDOMLEG. Twelve participants performed a series of double-leg and counterweighted single-leg DOMLEG and NDOMLEG ramp-exercise tests and 30-min constant-load trials. V̇o2peak was greater in the DOMLEG than in the NDOMLEG (2.87 ± 0.42 vs. 2.70 ± 0.39 L/min, P < 0.05). The difference in V̇o2peak persisted even after accounting for lean mass (P < 0.05). Similarly, MLSSp was greater in the DOMLEG than in the NDOMLEG (118 ± 31 vs. 109 ± 31 W; P < 0.05). Furthermore, the amplitude of the [HHb] signal during ramp exercise was larger in the DOMLEG than in the NDOMLEG during both double-leg (26.0 ± 8.4 vs. 20.2 ± 8.8 µM, P < 0.05) and counterweighted single-leg cycling (18.5 ± 7.9 vs. 14.9 ± 7.5 µM, P < 0.05). Additionally, the amplitudes of the [HHb] signal were highly to moderately correlated with the mode-specific V̇o2peak values (ranging from 0.91 to 0.54). These findings showed in a group of young men that maximal and submaximal aerobic capacities were greater in the DOMLEG than in the NDOMLEG and that superior peripheral adaptations of the DOMLEG may underpin these differences.NEW & NOTEWORTHY It is typically assumed that the dominant and nondominant legs contribute equally to the whole physiological responses. In this study, we found that the dominant leg achieved greater peak O2 uptake values, sustained greater power output while preserving whole body metabolic stability, and showed larger amplitudes of deoxygenation responses. These findings highlight heterogeneous aerobic capacities of the lower limbs, which have important implications when whole body physiological responses are examined.
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Affiliation(s)
- Danilo Iannetta
- Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
| | - Louis Passfield
- Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada.,School of Sport and Exercise Sciences, University of Kent, Canterbury, United Kingdom
| | - Ahmad Qahtani
- Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
| | - Martin J MacInnis
- Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
| | - Juan M Murias
- Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
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48
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Waldron M, Patterson SD, Jeffries O. Oral taurine improves critical power and severe-intensity exercise tolerance. Amino Acids 2019; 51:1433-1441. [PMID: 31482309 DOI: 10.1007/s00726-019-02775-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2019] [Accepted: 08/18/2019] [Indexed: 11/26/2022]
Abstract
This study investigated the effects of acute oral taurine ingestion on: (1) the power-time relationship using the 3-min all-out test (3MAOT); (2) time to exhaustion (TTE) 5% > critical power (CP) and (3) the estimated time to complete (Tlim) a range of fixed target intensities. Twelve males completed a baseline 3MAOT test on a cycle ergometer. Following this, a double-blind, randomised cross-over design was followed, where participants were allocated to one of four conditions, separated by 72 h: TTE + taurine; TTE + placebo; 3MAOT + taurine; 3MAOT + placebo. Taurine was provided at 50 mg kg-1, whilst the placebo was 3 mg kg-1 maltodextrin. CP was higher (P < 0.05) in taurine (212 ± 36 W) than baseline (197 ± 40 W) and placebo (193 ± 35 W). Work end power was not affected by supplement (P > 0.05), yet TTE 5% > CP increased (P < 0.05) by 1.7 min after taurine (17.7 min) compared to placebo (16.0 min) and there were higher (P < 0.001) estimated Tlim across all work targets. Acute supplementation of 50 mg kg-1 of taurine improved CP and estimated performance at a range of severe work intensities. Oral taurine can be taken prior to exercise to enhance endurance performance.
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Affiliation(s)
- Mark Waldron
- College of Engineering, Swansea University, Swansea, SA1 8EN, UK.
- School of Science and Technology, University of New England, Armidale, NSW, Australia.
| | | | - Owen Jeffries
- School of Biomedical Sciences, Newcastle University, Newcastle upon Tyne, UK
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49
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Clark IE, Vanhatalo A, Thompson C, Joseph C, Black MI, Blackwell JR, Wylie LJ, Tan R, Bailey SJ, Wilkins BW, Kirby BS, Jones AM. Dynamics of the power-duration relationship during prolonged endurance exercise and influence of carbohydrate ingestion. J Appl Physiol (1985) 2019; 127:726-736. [PMID: 31295069 DOI: 10.1152/japplphysiol.00207.2019] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
We tested the hypotheses that the parameters of the power-duration relationship, estimated as the end-test power (EP) and work done above EP (WEP) during a 3-min all-out exercise test (3MT), would be reduced progressively after 40 min, 80 min, and 2 h of heavy-intensity cycling and that carbohydrate (CHO) ingestion would attenuate the reduction in EP and WEP. Sixteen participants completed a 3MT without prior exercise (control), immediately after 40 min, 80 min, and 2 h of heavy-intensity exercise while consuming a placebo beverage, and also after 2 h of heavy-intensity exercise while consuming a CHO supplement (60 g/h CHO). There was no difference in EP measured without prior exercise (260 ± 37 W) compared with EP after 40 min (268 ± 39 W) or 80 min (260 ± 40 W) of heavy-intensity exercise; however, after 2 h EP was 9% lower compared with control (236 ± 47 W; P < 0.05). There was no difference in WEP measured without prior exercise (17.9 ± 3.3 kJ) compared with after 40 min of heavy-intensity exercise (16.1 ± 3.3 kJ), but WEP was lower (P < 0.05) than control after 80 min (14.7 ± 2.9 kJ) and 2 h (13.8 ± 2.7 kJ). Compared with placebo, CHO ingestion negated the reduction of EP following 2 h of heavy-intensity exercise (254 ± 49 W) but had no effect on WEP (13.5 ± 3.4 kJ). These results reveal a different time course for the deterioration of EP and WEP during prolonged endurance exercise and indicate that EP is sensitive to CHO availability.NEW & NOTEWORTHY The parameters of the power-duration relationship [critical power (CP) and the curvature constant (W')] have typically been considered to be static. Here we report the time course for reductions in CP and W', as estimated with the 3-min all-out cycle test, during 2 h of heavy-intensity exercise. We also show that carbohydrate ingestion during exercise preserves CP, but not W', without altering muscle glycogen depletion. These results provide new mechanistic and practical insight into the power-duration curve and its relationship to exercise-related fatigue development.
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Affiliation(s)
- Ida E Clark
- Sport and Health Sciences, College of Life and Environmental Sciences, St. Luke's Campus, University of Exeter, Exeter, United Kingdom
| | - Anni Vanhatalo
- Sport and Health Sciences, College of Life and Environmental Sciences, St. Luke's Campus, University of Exeter, Exeter, United Kingdom
| | - Christopher Thompson
- Sport and Health Sciences, College of Life and Environmental Sciences, St. Luke's Campus, University of Exeter, Exeter, United Kingdom
| | - Charlotte Joseph
- Sport and Health Sciences, College of Life and Environmental Sciences, St. Luke's Campus, University of Exeter, Exeter, United Kingdom
| | - Matthew I Black
- Sport and Health Sciences, College of Life and Environmental Sciences, St. Luke's Campus, University of Exeter, Exeter, United Kingdom
| | - Jamie R Blackwell
- Sport and Health Sciences, College of Life and Environmental Sciences, St. Luke's Campus, University of Exeter, Exeter, United Kingdom
| | - Lee J Wylie
- Sport and Health Sciences, College of Life and Environmental Sciences, St. Luke's Campus, University of Exeter, Exeter, United Kingdom
| | - Rachel Tan
- Sport and Health Sciences, College of Life and Environmental Sciences, St. Luke's Campus, University of Exeter, Exeter, United Kingdom
| | - Stephen J Bailey
- Sport and Health Sciences, College of Life and Environmental Sciences, St. Luke's Campus, University of Exeter, Exeter, United Kingdom
| | | | | | - Andrew M Jones
- Sport and Health Sciences, College of Life and Environmental Sciences, St. Luke's Campus, University of Exeter, Exeter, United Kingdom
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50
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Jones AM, Burnley M, Black MI, Poole DC, Vanhatalo A. The maximal metabolic steady state: redefining the 'gold standard'. Physiol Rep 2019; 7:e14098. [PMID: 31124324 PMCID: PMC6533178 DOI: 10.14814/phy2.14098] [Citation(s) in RCA: 148] [Impact Index Per Article: 29.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Revised: 04/25/2019] [Accepted: 04/27/2019] [Indexed: 02/06/2023] Open
Abstract
The maximal lactate steady state (MLSS) and the critical power (CP) are two widely used indices of the highest oxidative metabolic rate that can be sustained during continuous exercise and are often considered to be synonymous. However, while perhaps having similarities in principle, methodological differences in the assessment of these parameters typically result in MLSS occurring at a somewhat lower power output or running speed and exercise at CP being sustainable for no more than approximately 20-30 min. This has led to the view that CP overestimates the 'actual' maximal metabolic steady state and that MLSS should be considered the 'gold standard' metric for the evaluation of endurance exercise capacity. In this article we will present evidence consistent with the contrary conclusion: i.e., that (1) as presently defined, MLSS naturally underestimates the actual maximal metabolic steady state; and (2) CP alone represents the boundary between discrete exercise intensity domains within which the dynamic cardiorespiratory and muscle metabolic responses to exercise differ profoundly. While both MLSS and CP may have relevance for athletic training and performance, we urge that the distinction between the two concepts/metrics be better appreciated and that comparisons between MLSS and CP, undertaken in the mistaken belief that they are theoretically synonymous, is discontinued. CP represents the genuine boundary separating exercise in which physiological homeostasis can be maintained from exercise in which it cannot, and should be considered the gold standard when the goal is to determine the maximal metabolic steady state.
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Affiliation(s)
- Andrew M. Jones
- Sport and Health SciencesUniversity of ExeterSt. Luke's CampusExeterUnited Kingdom
| | - Mark Burnley
- School of Sport and Exercise SciencesUniversity of KentMedwayUnited Kingdom
| | - Matthew I. Black
- Sport and Health SciencesUniversity of ExeterSt. Luke's CampusExeterUnited Kingdom
| | - David C. Poole
- Department of KinesiologyKansas State UniversityManhattanKansas
| | - Anni Vanhatalo
- Sport and Health SciencesUniversity of ExeterSt. Luke's CampusExeterUnited Kingdom
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