101
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Gorostiaga EM, Garcia-Tabar I, Sánchez-Medina L. Response to commentaries on: "Over 55 years of critical power: fact or artifact?". Scand J Med Sci Sports 2022; 32:935-936. [PMID: 35403304 DOI: 10.1111/sms.14152] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Accepted: 02/03/2022] [Indexed: 01/21/2023]
Affiliation(s)
- Esteban M Gorostiaga
- Studies, Research and Sports Medicine Centre (CEIMD), Government of Navarre, Pamplona, Spain
| | - Ibai Garcia-Tabar
- Society, Sports and Physical Exercise Research Group (GIKAFIT), Department of Physical Education and Sport, Faculty of Education and Sport, University of the Basque Country (UPV/EHU), Vitoria-Gasteiz, Spain.,Biobara, GIKAFIT, Vitoria-Gasteiz, Spain
| | - Luis Sánchez-Medina
- Studies, Research and Sports Medicine Centre (CEIMD), Government of Navarre, Pamplona, Spain
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102
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Broxterman RM, Craig JC, Kirby BS. Critical Power: Over 95 years of evidence and evolution. Scand J Med Sci Sports 2022; 32:933-934. [PMID: 35403303 DOI: 10.1111/sms.14154] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Accepted: 01/18/2022] [Indexed: 01/21/2023]
Affiliation(s)
- Ryan M Broxterman
- Geriatric Research, Education, and Clinical Center, Salt Lake City VAMC, Salt Lake City, Utah, USA.,Department of Internal Medicine, University of Utah, Salt Lake City, Utah, USA.,Center on Aging, University of Utah, Salt Lake City, Utah, USA
| | - Jesse C Craig
- Department of Internal Medicine, University of Utah, Salt Lake City, Utah, USA
| | - Brett S Kirby
- Nike Sport Research Lab, Nike, Inc., Beaverton, Oregon, USA
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103
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Drobnic F, Lizarraga MA, Caballero-García A, Cordova A. Coenzyme Q 10 Supplementation and Its Impact on Exercise and Sport Performance in Humans: A Recovery or a Performance-Enhancing Molecule? Nutrients 2022; 14:1811. [PMID: 35565783 PMCID: PMC9104583 DOI: 10.3390/nu14091811] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Revised: 04/22/2022] [Accepted: 04/22/2022] [Indexed: 02/06/2023] Open
Abstract
Evidence exists to suggest that ROS induce muscular injury with a subsequent decrease in physical performance. Supplementation with certain antioxidants is important for physically active individuals to hasten recovery from fatigue and to prevent exercise damage. The use of nutritional supplements associated with exercise, with the aim of improving health, optimizing training or improving sports performance, is a scientific concern that not only drives many research projects but also generates great expectations in the field of their application in pathology. Since its discovery in the 1970s, coenzyme Q10 (CoQ10) has been one of the most controversial molecules. The interest in determining its true value as a bioenergetic supplement in muscle contraction, antioxidant or in the inflammatory process as a muscle protector in relation to exercise has been studied at different population levels of age, level of physical fitness or sporting aptitude, using different methodologies of effort and with the contribution of data corresponding to very diverse variables. Overall, in the papers reviewed, although the data are inconclusive, they suggest that CoQ10 supplementation may be an interesting molecule in health or disease in individuals without a pathological deficiency and when used for optimising exercise performance. Considering the results observed in the literature, and as a conclusion of this systematic review, we could say that it is an interesting molecule in sports performance. However, clear approaches should be considered when conducting future research.
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Affiliation(s)
| | | | - Alberto Caballero-García
- Department of Anatomy and Radiology, Faculty of Health Sciences, GIR: “Physical Exercise and Aging”, Campus Universitario “Los Pajaritos”, University of Valladolid, 42004 Soria, Spain;
| | - Alfredo Cordova
- Department of Biochemistry, Molecular Biology and Physiology, Faculty of Health Sciences, GIR: “Physical Exercise and Aging”, Campus Universitario “Los Pajaritos”, University of Valladolid, 42004 Soria, Spain;
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104
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Trade-Off Between Maximal Power Output and Fatigue Resistance of the Knee Extensors for Older Men. J Aging Phys Act 2022; 30:1003-1013. [PMID: 35453123 DOI: 10.1123/japa.2021-0384] [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: 09/14/2021] [Revised: 02/15/2022] [Accepted: 02/22/2022] [Indexed: 11/18/2022]
Abstract
This study investigated associations of fatigue resistance determined by an exercise-induced decrease in neuromuscular power with prefatigue neuromuscular strength and power of the knee extensors in 31 older men (65-88 years). A fatigue task consisted of 50 consecutive maximal effort isotonic knee extensions (resistance: 20% of prefatigue isometric maximal voluntary contraction torque) over a 70° range of motion. The average of the peak power values calculated from the 46th to 50th contractions during the fatigue task was normalized to the prefatigue peak power value, which was defined as neuromuscular fatigue resistance. Neuromuscular fatigue resistance was negatively associated with prefatigue maximal power output (r = -.530) but not with prefatigue maximal voluntary contraction torque (r = -.252). This result highlights a trade-off between prefatigue maximal power output and neuromuscular fatigue resistance, implying that an improvement in maximal power output might have a negative impact on neuromuscular fatigue resistance.
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105
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Sex Differences in VO 2max and the Impact on Endurance-Exercise Performance. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:ijerph19094946. [PMID: 35564339 PMCID: PMC9105160 DOI: 10.3390/ijerph19094946] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/07/2022] [Accepted: 04/15/2022] [Indexed: 02/04/2023]
Abstract
It was not until 1984 that women were permitted to compete in the Olympic marathon. Today, more women than men participate in road racing in all distances except the marathon where participation is near equal. From the period of 1985 to 2004, the women’s marathon record improved at a rate three times greater than men’s. This has led many to question whether women are capable of surpassing men despite the fact that there remains a 10–12% performance gap in all distance events. The progressive developments in sports performance research and training, beginning with A.V. Hill’s establishment of the concept of VO2max, have allowed endurance athletes to continue performance feats previously thought to be impossible. However, even today women are significantly underrepresented in sports performance research. By focusing more research on the female physiology and sex differences between men and women, we can better define how women differ from men in adapting to training and potentially use this information to improve endurance-exercise performance in women. The male advantage in endurance-exercise performance has commonly been attributed to their higher VO2max, even when expressed as mL/kg/min. It is widely known that oxygen delivery is the primary limiting factor in elite athletes when it comes to improving VO2max, but little research has explored the sex differences in oxygen delivery. Thus, the purpose of this review is to highlight what is known about the sex differences in the physiological factors contributing to VO2max, more specifically oxygen delivery, and the impacts on performance.
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106
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Caen K, Bourgois JG, Stassijns E, Boone J. A longitudinal study on the interchangeable use of whole-body and local exercise thresholds in cycling. Eur J Appl Physiol 2022; 122:1657-1670. [PMID: 35435465 PMCID: PMC9014408 DOI: 10.1007/s00421-022-04942-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Accepted: 03/23/2022] [Indexed: 12/03/2022]
Abstract
Purpose This study longitudinally examined the interchangeable use of critical power (CP), the maximal lactate steady state (MLSS) and the respiratory compensation point (RCP) (i.e., whole-body thresholds), and breakpoints in muscle deoxygenation (m[HHb]BP) and muscle activity (iEMGBP) (i.e., local thresholds). Methods Twenty-one participants were tested on two timepoints (T1 and T2) with a 4-week period (study 1: 10 women, age = 27 ± 3 years, \documentclass[12pt]{minimal}
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\begin{document}$$\dot{V}{\text{O}}_{{2{\text{peak}}}}$$\end{document}V˙O2peak = 43.2 ± 7.3 mL min−1kg−1) or a 12-week period (study 2: 11 men, age = 25 ± 4 years, \documentclass[12pt]{minimal}
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\begin{document}$$\dot{V}{\text{O}}_{{2{\text{peak}}}}$$\end{document}V˙O2peak = 47.7 ± 5.9 mL min−1 kg−1) in between. The test battery included one ramp incremental test (to determine RCP, m[HHb]BP and iEMGBP) and a series of (sub)maximal constant load tests (to determine CP and MLSS). All thresholds were expressed as oxygen uptake (\documentclass[12pt]{minimal}
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\begin{document}$$\dot{V}{\text{O}}_{2}$$\end{document}V˙O2) and equivalent power output (PO) for comparison. Results None of the thresholds were significantly different in study 1 (\documentclass[12pt]{minimal}
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\begin{document}$$\dot{V}{\text{O}}_{2}$$\end{document}V˙O2: P = 0.143, PO: P = 0.281), but differences between whole-body and local thresholds were observed in study 2 (\documentclass[12pt]{minimal}
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\begin{document}$$\dot{V}{\text{O}}_{2}$$\end{document}V˙O2: P < 0.001, PO: P = 0.024). Whole-body thresholds showed better 4-week test–retest reliability (TEM = 88–125 mL min−1 or 6–10 W, ICC = 0.94–0.98) compared to local thresholds (TEM = 189–195 mL min−1 or 15–18 W, ICC = 0.58–0.89). All five thresholds were strongly associated at T1 and T2 (r = 0.75–0.99), but their changes from T1 to T2 were mostly uncorrelated (r = − 0.41–0.83). Conclusion Whole-body thresholds (CP/MLSS/RCP) showed a close and consistent coherence taking into account a 3–6%-bandwidth of typical variation. In contrast, local thresholds (m[HHb]BP/iEMGBP) were characterized by higher variability and did not consistently coincide with the whole-body thresholds. In addition, we found that most thresholds evolved independently of each other over time. Together, these results do not justify the interchangeable use of whole-body and local exercise thresholds in practice.
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Affiliation(s)
- Kevin Caen
- Department of Movement and Sports Sciences, Ghent University, Watersportlaan 2, 9000, Ghent, Belgium.,Center of Sports Medicine, Ghent University Hospital, Ghent, Belgium
| | - Jan G Bourgois
- Department of Movement and Sports Sciences, Ghent University, Watersportlaan 2, 9000, Ghent, Belgium.,Center of Sports Medicine, Ghent University Hospital, Ghent, Belgium
| | - Eva Stassijns
- Department of Movement and Sports Sciences, Ghent University, Watersportlaan 2, 9000, Ghent, Belgium
| | - Jan Boone
- Department of Movement and Sports Sciences, Ghent University, Watersportlaan 2, 9000, Ghent, Belgium. .,Center of Sports Medicine, Ghent University Hospital, Ghent, Belgium.
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107
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Korzeniewski B. V˙O2 On-Kinetics-Critical Power Relationship: Correlation But Not Direct Causal Link. Exerc Sport Sci Rev 2022; 50:104. [PMID: 35275896 DOI: 10.1249/jes.0000000000000286] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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108
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Saif A, Khan Z, Parveen A. Critical power as a fatigue threshold in sports: A scoping review. Sci Sports 2022. [DOI: 10.1016/j.scispo.2021.05.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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109
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A century of exercise physiology: key concepts on coupling respiratory oxygen flow to muscle energy demand during exercise. Eur J Appl Physiol 2022; 122:1317-1365. [PMID: 35217911 PMCID: PMC9132876 DOI: 10.1007/s00421-022-04901-x] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Accepted: 01/25/2022] [Indexed: 12/26/2022]
Abstract
After a short historical account, and a discussion of Hill and Meyerhof’s theory of the energetics of muscular exercise, we analyse steady-state rest and exercise as the condition wherein coupling of respiration to metabolism is most perfect. The quantitative relationships show that the homeostatic equilibrium, centred around arterial pH of 7.4 and arterial carbon dioxide partial pressure of 40 mmHg, is attained when the ratio of alveolar ventilation to carbon dioxide flow (\documentclass[12pt]{minimal}
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\begin{document}$${\dot{V}}_{A}/{\dot{V}}_{R}{CO}_{2}$$\end{document}V˙A/V˙RCO2) is − 21.6. Several combinations, exploited during exercise, of pertinent respiratory variables are compatible with this equilibrium, allowing adjustment of oxygen flow to oxygen demand without its alteration. During exercise transients, the balance is broken, but the coupling of respiration to metabolism is preserved when, as during moderate exercise, the respiratory system responds faster than the metabolic pathways. At higher exercise intensities, early blood lactate accumulation suggests that the coupling of respiration to metabolism is transiently broken, to be re-established when, at steady state, blood lactate stabilizes at higher levels than resting. In the severe exercise domain, coupling cannot be re-established, so that anaerobic lactic metabolism also contributes to sustain energy demand, lactate concentration goes up and arterial pH falls continuously. The \documentclass[12pt]{minimal}
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\begin{document}$${\dot{V}}_{A}/{\dot{V}}_{R}{CO}_{2}$$\end{document}V˙A/V˙RCO2 decreases below − 21.6, because of ensuing hyperventilation, while lactate keeps being accumulated, so that exercise is rapidly interrupted. The most extreme rupture of the homeostatic equilibrium occurs during breath-holding, because oxygen flow from ambient air to mitochondria is interrupted. No coupling at all is possible between respiration and metabolism in this case.
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110
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Tschakert G, Handl T, Weiner L, Birnbaumer P, Mueller A, Groeschl W, Hofmann P. Exercise duration: Independent effects on acute physiologic responses and the need for an individualized prescription. Physiol Rep 2022; 10:e15168. [PMID: 35146958 PMCID: PMC8831952 DOI: 10.14814/phy2.15168] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 11/30/2021] [Accepted: 12/30/2021] [Indexed: 11/24/2022] Open
Abstract
An individualization of exercise prescription is implemented mainly in terms of intensity but not for duration. To survey the need for an individualized exercise duration prescription, we investigated acute physiologic responses during constant‐load exercise of maximal duration (tmax) and determined so‐called duration thresholds. Differences between absolute (min) and relative terms (% tmax) of exercise duration were analyzed. Healthy young and trained male and female participants (n = 11) performed an incremental exercise test and one tmax constant‐load exercise test at a target intensity of 10% of maximal power output below the second lactate turn point (LTP2). Blood lactate, heart rate, and spirometric data were measured during all tests. tmax was markedly different across subjects (69.6 ± 14.8 min; range: 40–90 min). However, distinct duration phases separated by duration thresholds (DTh) were found in most measured variables. These duration thresholds (except DTh1) were significantly related to tmax (DTh2: r2 = 0.90, p < 0.0001; DTh3: r2 = 0.98, p < 0.0001) and showed substantial interindividual differences if expressed in absolute terms (DTh2: 24.8 ± 6.0 min; DTh3: 47.4 ± 10.6 min) but not in relative terms (DTh2: 35.4 ± 2.7% tmax; DTh3: 67.9 ± 2.4% tmax). Our data showed that (1) maximal duration was individually different despite the same relative intensity, (2) duration thresholds that were related to tmax could be determined in most measured variables, and (3) duration thresholds were comparable between subjects if expressed in relative terms. We therefore conclude that duration needs to be concerned as an independent variable of exercise prescription.
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Affiliation(s)
- Gerhard Tschakert
- Institute of Human Movement Science, Sport & Health, University of Graz, Graz, Austria
| | - Tanja Handl
- Institute of Human Movement Science, Sport & Health, University of Graz, Graz, Austria
| | - Lena Weiner
- Institute of Human Movement Science, Sport & Health, University of Graz, Graz, Austria
| | - Philipp Birnbaumer
- Institute of Human Movement Science, Sport & Health, University of Graz, Graz, Austria
| | - Alexander Mueller
- Institute of Human Movement Science, Sport & Health, University of Graz, Graz, Austria
| | - Werner Groeschl
- Institute of Human Movement Science, Sport & Health, University of Graz, Graz, Austria
| | - Peter Hofmann
- Institute of Human Movement Science, Sport & Health, University of Graz, Graz, Austria
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111
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Petrigna L, Karsten B, Delextrat A, Pajaujiene S, Mani D, Paoli A, Palma A, Bianco A. An updated methodology to estimate critical velocity in front crawl swimming: A scoping review. Sci Sports 2022. [DOI: 10.1016/j.scispo.2021.06.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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112
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Baláš J, Gajdošík J, Giles D, Fryer S. The Estimation of Critical Angle in Climbing as a Measure of Maximal Metabolic Steady State. Front Physiol 2022; 12:792376. [PMID: 35069253 PMCID: PMC8766676 DOI: 10.3389/fphys.2021.792376] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2021] [Accepted: 11/30/2021] [Indexed: 11/30/2022] Open
Abstract
Purpose: Sport climbing is a technical, self-paced sport, and the workload is highly variable and mainly localized to the forearm flexors. It has not proved effective to control intensity using measures typical of other sports, such as gas exchange thresholds, heart rate, or blood lactate. Therefore, the purposes of the study were to (1) determine the possibility of applying the mathematical model of critical power to the estimation of a critical angle (CA) as a measure of maximal metabolic steady state in climbing and (2) to compare this intensity with the muscle oxygenation breakpoint (MOB) determined during an exhaustive climbing task. Materials and Methods: Twenty-seven sport climbers undertook three to five exhaustive ascents on a motorized treadwall at differing angles to estimate CA, and one exhaustive climbing test with a progressive increase in angle to determine MOB, assessed using near-infrared spectroscopy (NIRS). Results: Model fit for estimated CA was very high (R2 = 0.99; SEE = 1.1°). The mean peak angle during incremental test was −17 ± 5°, and CA from exhaustive trials was found at −2.5 ± 3.8°. Nine climbers performing the ascent 2° under CA were able to sustain the task for 20 min with perceived exertion at 12.1 ± 1.9 (RPE). However, climbing 2° above CA led to task failure after 15.9 ± 3.0 min with RPE = 16.4 ± 1.9. When MOB was plotted against estimated CA, good agreement was stated (ICC = 0.80, SEM = 1.5°). Conclusion: Climbers, coaches, and researchers may use a predefined route with three to five different wall angles to estimate CA as an analog of critical power to determine a maximal metabolic steady state in climbing. Moreover, a climbing test with progressive increases in wall angle using MOB also appears to provide a valid estimate of CA.
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Affiliation(s)
- Jiří Baláš
- Faculty of Physical Education and Sport, Charles University, Prague, Czechia
| | - Jan Gajdošík
- Faculty of Physical Education and Sport, Charles University, Prague, Czechia
| | - David Giles
- Lattice Training Ltd., Chesterfield, United Kingdom
| | - Simon Fryer
- School of Sport and Exercise, University of Gloucestershire, Cheltenham, United Kingdom
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113
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Salas-Montoro JA, Mateo March M, Sánchez-Muñoz C, Zabala M. Determination of second lactate threshold using near-infrared spectroscopy in elite cyclists. Int J Sports Med 2022; 43:721-728. [PMID: 35021246 DOI: 10.1055/a-1738-0252] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
The use of near-infrared spectroscopy could be an interesting alternative to other invasive or expensive methods to estimate the second lactate threshold. Our objective was to compare the intensities of the muscle oxygen saturation breakpoint obtained with the Humon Hex and the second lactate threshold in elite cyclists. Ninety cyclists performed a maximal graded exercise test. Blood capillary lactate was obtained at the end of steps and muscle oxygenation was continuously monitored. There were no differences (p>0.05) between muscle oxygen oxygenation breakpoint and second lactate threshold neither in power nor in heart rate, nor when these values were relativized as a percentage of maximal aerobic power or maximum heart rate. There were also no differences when men and women were studied separately. Both methods showed a highly correlation in power (r=0.914), percentage of maximal aerobic power (r=0.752), heart rate (r=0.955), and percentage of maximum heart rate (r=0.903). Bland-Altman resulted in a mean difference of 0.05±0.27 W·kg-1, 0.91±4.93%, 0.63±3.25 bpm, and 0.32±1.69% for power, percentage of maximal aerobic power, heart rate and percentage of maximum heart rate respectively. These findings suggest that Humon may be a non-invasive and low-cost alternative to estimate the second lactate threshold intensity in elite cyclists.
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Affiliation(s)
- José-Antonio Salas-Montoro
- Department of Physical Education and Sport, Faculty of Sport Sciences, University of Granada, Granada, Spain
| | - Manuel Mateo March
- Health Psichology, Sport Research Centre, Miguel Hernandez University of Elche, Alicante, Spain.,BMX, Spanish Cycling Federation, Alicante, Spain
| | - Cristóbal Sánchez-Muñoz
- Department of Physical Activity and Sport, Faculty of Physical Activity and Sport Sciences (University of Granada), Granada, Spain
| | - Mikel Zabala
- Department of Physical Activity and Sport, Faculty of Physical Activity and Sport Sciences (University of Granada), Granada, Spain.,Department of Physical Education and Sport, Faculty of Physical Activity and Sport Sciences, Granada, Spain
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114
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Briand J, Tremblay J, Thibault G. Can Popular High-Intensity Interval Training (HIIT) Models Lead to Impossible Training Sessions? Sports (Basel) 2022; 10:sports10010010. [PMID: 35050975 PMCID: PMC8822890 DOI: 10.3390/sports10010010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Revised: 12/28/2021] [Accepted: 12/30/2021] [Indexed: 01/25/2023] Open
Abstract
High-Intensity Interval Training (HIIT) is a time-efficient training method suggested to improve health and fitness for the clinical population, healthy subjects, and athletes. Many parameters can impact the difficulty of HIIT sessions. This study aims to highlight and explain, through logical deductions, some limitations of the Skiba and Coggan models, widely used to prescribe HIIT sessions in cycling. We simulated 6198 different HIIT training sessions leading to exhaustion, according to the Skiba and Coggan-Modified (modification of the Coggan model with the introduction of an exhaustion criterion) models, for three fictitious athlete profiles (Time-Trialist, All-Rounder, Sprinter). The simulation revealed impossible sessions (i.e., requiring athletes to surpass their maximal power output over the exercise interval duration), characterized by a few short exercise intervals, performed in the severe and extreme intensity domains, alternating with long recovery bouts. The fraction of impossible sessions depends on the athlete profile and ranges between 4.4 and 22.9% for the Skiba model and 0.6 and 3.2% for the Coggan-Modified model. For practitioners using these HIIT models, this study highlights the importance of understanding these models’ inherent limitations and mathematical assumptions to draw adequate conclusions from their use to prescribe HIIT sessions.
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Affiliation(s)
- Jérémy Briand
- Institut National du Sport du Québec, 4141 Avenue Pierre-De-Coubertin, Montreal, QC H1V 3N7, Canada; (J.B.); (G.T.)
- École de Kinésiologie et des Sciences de l’Activité Physique, Faculté de Médecine, Université de Montréal, 2100 Boulevard Édouard-Montpetit, Montreal, QC H3T 1J4, Canada
| | - Jonathan Tremblay
- École de Kinésiologie et des Sciences de l’Activité Physique, Faculté de Médecine, Université de Montréal, 2100 Boulevard Édouard-Montpetit, Montreal, QC H3T 1J4, Canada
- Correspondence:
| | - Guy Thibault
- Institut National du Sport du Québec, 4141 Avenue Pierre-De-Coubertin, Montreal, QC H1V 3N7, Canada; (J.B.); (G.T.)
- École de Kinésiologie et des Sciences de l’Activité Physique, Faculté de Médecine, Université de Montréal, 2100 Boulevard Édouard-Montpetit, Montreal, QC H3T 1J4, Canada
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115
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Kim KJ, Rivas E, Prejean B, Frisco D, Young M, Downs M. Novel Computerized Method for Automated Determination of Ventilatory Threshold and Respiratory Compensation Point. Front Physiol 2022; 12:782167. [PMID: 34975535 PMCID: PMC8718913 DOI: 10.3389/fphys.2021.782167] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Accepted: 11/18/2021] [Indexed: 11/29/2022] Open
Abstract
Introduction: The ventilatory threshold (named as VT1) and the respiratory compensation point (named as VT2) describe prominent changes of metabolic demand and exercise intensity domains during an incremental exercise test. Methods: A novel computerized method based on the optimization method was developed for automatically determining VT1 and VT2 from expired air during a progressive maximal exercise test. A total of 109 peak cycle tests were performed by members of the US astronaut corps (74 males and 35 females). We compared the automatically determined VT1 and VT2 values against the visual subjective and independent analyses of three trained evaluators. We also characterized VT1 and VT2 and the respective absolute and relative work rates and distinguished differences between sexes. Results: The automated compared to the visual subjective values were analyzed for differences with t test, for agreement with Bland–Altman plots, and for equivalence with a two one-sided test approach. The results showed that the automated and visual subjective methods were statistically equivalent, and the proposed approach reliably determined VT1 and VT2 values. Females had lower absolute O2 uptake, work rate, and ventilation, and relative O2 uptake at VT1 and VT2 compared to men (p ≤ 0.04). VT1 and VT2 occurred at a greater relative percentage of their peak VO2 for females (67 and 88%) compared to males (55 and 74%; main effect for sex: p < 0.001). Overall, VT1 occurred at 58% of peak VO2, and VT2 occurred at 79% of peak VO2 (p < 0.0001). Conclusion: Improvements in determining of VT1 and VT2 by automated analysis are time efficient, valid, and comparable to subjective visual analysis and may provide valuable information in research and clinical practice as well as identifying exercise intensity domains of crewmembers in space.
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Affiliation(s)
| | | | | | | | | | - Meghan Downs
- NASA Johnson Space Center, Houston, TX, United States
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116
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Ozkaya O, Balci GA, As H, Cabuk R, Norouzi M. Grey Zone: A Gap Between Heavy and Severe Exercise Domain. J Strength Cond Res 2022; 36:113-120. [PMID: 32149880 DOI: 10.1519/jsc.0000000000003427] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/20/2023]
Abstract
ABSTRACT Ozkaya, O, Balci, GA, As, H, Cabuk, R, and Norouzi, M. Grey zone: A gap between heavy and severe exercise domain. J Strength Cond Res 36(1): 113-120, 2022-The aim of this study was to determine a critical threshold (CT) interpreted as "the highest exercise intensity where V̇o2 can be stabilized before reaching 95% of V̇o2max (V̇o2peak)" and compare it with commonly used anaerobic threshold indices. Ten well-trained male cyclists volunteered for this study. Ventilatory threshold (VT) was determined from incremental tests. Multisession constant-load trials were performed to reveal V̇o2max. Mathematically modeled critical power (CP) was estimated through the best individual fit parameter method. Maximal lactate steady state (MLSS) was detected by 30-minute constant-load exercises. The individual CT load of each cyclist was tested by constant-load exercises to exhaustion with +15 W intervals until minimal power output to elicit V̇o2peak. The results showed that work rate corresponding to CT (329.5 ± 41.5 W) was significantly greater than that of the MLSS (269.5 ± 38.5 W; p = 0.000), VT (279.6 ± 33 W; p = 0.000), and CP (306.3 ± 39.4 W; p = 0.000), and CP overestimated both VT and MLSS (p = 0.000). There was no significant V̇o2 difference between the 10th and 30th minute of MLSS and MLSS + 15 W exercise (0.36-0.13 ml·min-1·kg-1; p = 0.621). Exercising V̇o2 response of MLSS + 15 W could not exceed the level of 95% V̇o2max (57.02 ± 3.87 ml·min-1·kg-1 and 87.2 ± 3.1% of V̇o2max; p = 0.000), whereas V̇o2 responses greater than 95% of V̇o2max were always attained during exercises performed at CT + 15 W (64.52 ± 4.37 ml·min-1·kg-1 and 98.6 ± 1% of V̇o2max; p > 0.05). In conclusion, this study indicates that there is a "grey zone" between heavy and severe exercise domain. This information may play a key role in enhancing athletic performance by improving the quality of training programs.
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Affiliation(s)
- Ozgur Ozkaya
- Coaching Education Department, Faculty of Sport Sciences, Ege University, Bornova, Turkey
| | - Gorkem Aybars Balci
- Coaching Education Department, Faculty of Sport Sciences, Ege University, Bornova, Turkey
| | - Hakan As
- Department of Sport and Health Sciences, Faculty of Sport Sciences, Ege University, Bornova, Turkey ; and
| | - Refik Cabuk
- School of Physical Education and Sports, Coaching Education Department, Bayburt University, Bayburt, Turkey
| | - Mahdi Norouzi
- Department of Sport and Health Sciences, Faculty of Sport Sciences, Ege University, Bornova, Turkey ; and
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117
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Hutchinson MJ, Goosey-Tolfrey VL. Rethinking aerobic exercise intensity prescription in adults with spinal cord injury: time to end the use of "moderate to vigorous" intensity? Spinal Cord 2022; 60:484-490. [PMID: 34880442 PMCID: PMC9209328 DOI: 10.1038/s41393-021-00733-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Revised: 11/19/2021] [Accepted: 11/23/2021] [Indexed: 11/13/2022]
Abstract
STUDY DESIGN Cohort study. OBJECTIVES To investigate and critique different methods for aerobic exercise intensity prescription in adults with spinal cord injury (SCI). SETTING University laboratory in Loughborough, UK. METHODS Trained athletes were split into those with paraplegia (PARA; n = 47), tetraplegia (TETRA; n = 20) or alternate health condition (NON-SCI; n = 67). Participants completed a submaximal step test with 3 min stages, followed by graded exercise test to exhaustion. Handcycling, arm crank ergometry or wheelchair propulsion were performed depending on the sport of the participant. Oxygen uptake (V̇O2), heart rate (HR), blood lactate concentration ([BLa]) and ratings of perceived exertion (RPE) on Borg's RPE scale were measured throughout. Lactate thresholds were identified according to log-V̇O2 plotted against log-[BLa] (LT1) and 1.5 mmol L-1 greater than LT1 (LT2). These were used to demarcate moderate (<LT1), heavy (>LT1, < LT2) and severe (>LT2) exercise intensity domains. RESULTS Associations between percentage of peak V̇O2 (%V̇O2peak) and HR (%HRpeak) with RPE differed between PARA and TETRA. At LT1 and LT2, %V̇O2peak and %HRpeak were significantly greater in TETRA compared to PARA and NON-SCI (P < 0.05). The variation in %V̇O2peak and %HRpeak at lactate thresholds resulted in large variability in the domain distribution at fixed %V̇O2peak and %HRpeak. CONCLUSIONS Fixed %V̇O2peak and %HRpeak should not be used for aerobic exercise intensity prescription in adults with SCI as the method does not lead to uniform exercise intensity domain distribution.
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Affiliation(s)
- Michael J. Hutchinson
- grid.6571.50000 0004 1936 8542Peter Harrison Centre for Disability Sport, School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, UK
| | - Victoria L. Goosey-Tolfrey
- grid.6571.50000 0004 1936 8542Peter Harrison Centre for Disability Sport, School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, UK
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118
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Teso M, Colosio AL, Pogliaghi S. An Intensity-dependent Slow Component of HR Interferes with Accurate Exercise Implementation in Postmenopausal Women. Med Sci Sports Exerc 2021; 54:655-664. [PMID: 34967799 PMCID: PMC8920010 DOI: 10.1249/mss.0000000000002835] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Heart rate (HR) targets are commonly used to administer exercise intensity in sport and clinical practice. However, as exercise protracts, a time-dependent dissociation between HR and metabolism can lead to a misprescription of the intensity ingredient of the exercise dose.
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Affiliation(s)
- Massimo Teso
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy Department of Movement and Sports Sciences, Ghent University, Watersportlaan2, Ghent, Belgium
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119
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Ettema M, Brurok B, Baumgart JK. Test-Retest Reliability of Physiological Variables During Submaximal Seated Upper-Body Poling in Able-Bodied Participants. Front Physiol 2021; 12:749356. [PMID: 34916954 PMCID: PMC8669804 DOI: 10.3389/fphys.2021.749356] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Accepted: 10/29/2021] [Indexed: 11/16/2022] Open
Abstract
Purpose: To investigate the test–retest reliability of physiological variables across four different test days and four different submaximal exercise intensities during seated upper-body poling (UBP). Methods: Thirteen abled-bodied, upper-body trained men (age 29±3years; body mass 84±12kg; height 183±5cm) performed four submaximal 4-min stages of seated UBP on four separate test days. The four submaximal stages were set at individual power outputs corresponding to a rating of perceived exertion of 9, 11, 13, and 15. The absolute reliability for pairwise test-day comparisons of the physiological variables was investigated with the smallest detectable change percentage (%SDC) and the relative reliability with the interclass correlation coefficient (ICC). Results: Absolute and relative reliability across test-day comparisons and submaximal stages were moderate to excellent for all variables investigated (V̇O2 – %SDC range: 5–13%, ICC range: 0.93–0.99; HR – %SDC range: 6–9%, ICC range: 0.91–0.97) other than blood lactate, for which absolute reliability was poor and relative reliability highly variable (%SDC range: 26–69%, ICC range: 0.44–0.92). Furthermore, absolute and relative reliability were consistent across the low-to-moderate exercise intensity spectrum and across test days. Conclusion: Absolute and relative test–retest reliability were acceptable for all investigated physiological variables but blood lactate. The consistent test–retest reliability across the exercise intensity spectrum and across test days indicates that a familiarization period to the specific exercise modality may not be necessary. For generalizability, these findings need to be confirmed in athletes with a disability by future large-scale studies.
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Affiliation(s)
- Marlou Ettema
- Centre for Elite Sports Research, Department of Neuromedicine and Movement science, Norwegian University of Science and Technology, Trondheim, Norway.,Department of Human Movement Sciences, Faculty of Behavioural and Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, Amsterdam, Netherlands
| | - Berit Brurok
- Department of Physical Medicine and Rehabilitation, St. Olav's University Hospital, Trondheim, Norway
| | - Julia Kathrin Baumgart
- Centre for Elite Sports Research, Department of Neuromedicine and Movement science, Norwegian University of Science and Technology, Trondheim, Norway
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120
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Baumgart JK, Ettema G, Griggs KE, Goosey-Tolfrey VL, Leicht CA. A Reappraisal of Ventilatory Thresholds in Wheelchair Athletes With a Spinal Cord Injury: Do They Really Exist? Front Physiol 2021; 12:719341. [PMID: 34899368 PMCID: PMC8664409 DOI: 10.3389/fphys.2021.719341] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Accepted: 10/27/2021] [Indexed: 11/13/2022] Open
Abstract
The ventilatory threshold (VT) separates low- from moderate-intensity exercise, the respiratory compensation point (RCP) moderate- from high-intensity exercise. Both concepts assume breakpoints in respiratory data. However, the objective determination of the VT and RCP using breakpoint models during upper-body modality exercise in wheelchair athletes with spinal cord injury (SCI) has received little attention. Therefore, the aim of this study was to compare the fit of breakpoint models (i.e., two linear regression lines) with continuous no-breakpoint models (i.e., exponential curve/second-order polynomial) to respiratory data obtained during a graded wheelchair exercise test to exhaustion. These fits were compared employing adjusted R2, and blocked bootstrapping was used to derive estimates of a median and 95% confidence intervals (CI). V̇O2-V̇CO2 and V̇E/V̇O2-time data were assessed for the determination of the VT, and V̇CO2-V̇E and V̇E/V̇CO2-time data for the determination of the RCP. Data of 9 wheelchair athletes with tetraplegia and 8 with paraplegia were evaluated. On an overall group-level, there was an overlap in the adjusted R2 median ± 95% CI between the breakpoint and the no-breakpoint models for determining the VT (V̇O2-V̇CO2: 0.991 ± 0.003 vs. 0.990 ± 0.003; V̇E/V̇O2-time: 0.792 ± 0.101 vs. 0.782 ± 0.104, respectively) and RCP (V̇E-V̇CO2: 0.984 ± 0.004 vs. 0.984 ± 0.004; V̇E/V̇CO2-time: 0.729 ± 0.064 vs. 0.691 ± 0.063, respectively), indicating similar model fit. We offer two lines of reasoning: (1) breakpoints in these respiratory data exist but are too subtle to result in a significant difference in adjusted R2 between the investigated breakpoint and no-breakpoint models; (2) breakpoints do not exist, as has been argued previously.
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Affiliation(s)
- Julia Kathrin Baumgart
- Department of Neuromedicine and Movement Science, Centre for Elite Sports Research, Norwegian University of Science and Technology, Trondheim, Norway
| | - Gertjan Ettema
- Department of Neuromedicine and Movement Science, Centre for Elite Sports Research, Norwegian University of Science and Technology, Trondheim, Norway
| | - Katy E Griggs
- The Peter Harrison Centre for Disability Sport, School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, United Kingdom.,Department of Engineering, School of Science and Technology, Nottingham Trent University, Nottingham, United Kingdom
| | - Victoria Louise Goosey-Tolfrey
- The Peter Harrison Centre for Disability Sport, School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, United Kingdom
| | - Christof Andreas Leicht
- The Peter Harrison Centre for Disability Sport, School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, United Kingdom
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121
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Rothschild JA, Islam H, Bishop DJ, Kilding AE, Stewart T, Plews DJ. Factors Influencing AMPK Activation During Cycling Exercise: A Pooled Analysis and Meta-Regression. Sports Med 2021; 52:1273-1294. [PMID: 34878641 DOI: 10.1007/s40279-021-01610-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/22/2021] [Indexed: 01/14/2023]
Abstract
BACKGROUND The 5' adenosine monophosphate (AMP)-activated protein kinase (AMPK) is a cellular energy sensor that is activated by increases in the cellular AMP/adenosine diphosphate:adenosine triphosphate (ADP:ATP) ratios and plays a key role in metabolic adaptations to endurance training. The degree of AMPK activation during exercise can be influenced by many factors that impact on cellular energetics, including exercise intensity, exercise duration, muscle glycogen, fitness level, and nutrient availability. However, the relative importance of these factors for inducing AMPK activation remains unclear, and robust relationships between exercise-related variables and indices of AMPK activation have not been established. OBJECTIVES The purpose of this analysis was to (1) investigate correlations between factors influencing AMPK activation and the magnitude of change in AMPK activity during cycling exercise, (2) investigate correlations between commonly reported measures of AMPK activation (AMPK-α2 activity, phosphorylated (p)-AMPK, and p-acetyl coenzyme A carboxylase (p-ACC), and (3) formulate linear regression models to determine the most important factors for AMPK activation during exercise. METHODS Data were pooled from 89 studies, including 982 participants (93.8% male, maximal oxygen consumption [[Formula: see text]] 51.9 ± 7.8 mL kg-1 min-1). Pearson's correlation analysis was performed to determine relationships between effect sizes for each of the primary outcome markers (AMPK-α2 activity, p-AMPK, p-ACC) and factors purported to influence AMPK signaling (muscle glycogen, carbohydrate ingestion, exercise duration and intensity, fitness level, and muscle metabolites). General linear mixed-effect models were used to examine which factors influenced AMPK activation. RESULTS Significant correlations (r = 0.19-0.55, p < .05) with AMPK activity were found between end-exercise muscle glycogen, exercise intensity, and muscle metabolites phosphocreatine, creatine, and free ADP. All markers of AMPK activation were significantly correlated, with the strongest relationship between AMPK-α2 activity and p-AMPK (r = 0.56, p < 0.001). The most important predictors of AMPK activation were the muscle metabolites and exercise intensity. CONCLUSION Muscle glycogen, fitness level, exercise intensity, and exercise duration each influence AMPK activity during exercise when all other factors are held constant. However, disrupting cellular energy charge is the most influential factor for AMPK activation during endurance exercise.
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Affiliation(s)
- Jeffrey A Rothschild
- Sports Performance Research Institute New Zealand (SPRINZ), Auckland University of Technology, Auckland, New Zealand.
| | - Hashim Islam
- School of Health and Exercise Sciences, University of British Columbia Okanagan, Kelowna, BC, Canada
| | - David J Bishop
- Institute for Health and Sport (iHeS), Victoria University, Melbourne, VIC, Australia.,School of Medical and Health Sciences, Edith Cowan University, Joondalup, WA, Australia
| | - Andrew E Kilding
- Sports Performance Research Institute New Zealand (SPRINZ), Auckland University of Technology, Auckland, New Zealand
| | - Tom Stewart
- Sports Performance Research Institute New Zealand (SPRINZ), Auckland University of Technology, Auckland, New Zealand
| | - Daniel J Plews
- Sports Performance Research Institute New Zealand (SPRINZ), Auckland University of Technology, Auckland, New Zealand
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122
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Bei Y, Wang L, Ding R, Che L, Fan Z, Gao W, Liang Q, Lin S, Liu S, Lu X, Shen Y, Wu G, Yang J, Zhang G, Zhao W, Guo L, Xiao J. Animal exercise studies in cardiovascular research: Current knowledge and optimal design-A position paper of the Committee on Cardiac Rehabilitation, Chinese Medical Doctors' Association. JOURNAL OF SPORT AND HEALTH SCIENCE 2021; 10:660-674. [PMID: 34454088 PMCID: PMC8724626 DOI: 10.1016/j.jshs.2021.08.002] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2020] [Revised: 05/09/2021] [Accepted: 07/11/2021] [Indexed: 05/02/2023]
Abstract
Growing evidence has demonstrated exercise as an effective way to promote cardiovascular health and protect against cardiovascular diseases However, the underlying mechanisms of the beneficial effects of exercise have yet to be elucidated. Animal exercise studies are widely used to investigate the key mechanisms of exercise-induced cardiovascular protection. However, standardized procedures and well-established evaluation indicators for animal exercise models are needed to guide researchers in carrying out effective, high-quality animal studies using exercise to prevent and treat cardiovascular diseases. In our review, we present the commonly used animal exercise models in cardiovascular research and propose a set of standard procedures for exercise training, emphasizing the appropriate measurements and analysis in these chronic exercise models. We also provide recommendations for optimal design of animal exercise studies in cardiovascular research, including the choice of exercise models, control of exercise protocols, exercise at different stages of disease, and other considerations, such as age, sex, and genetic background. We hope that this position paper will promote basic research on exercise-induced cardiovascular protection and pave the way for successful translation of exercise studies from bench to bedside in the prevention and treatment of cardiovascular diseases.
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Affiliation(s)
- Yihua Bei
- Institute of Geriatrics, Affiliated Nantong Hospital of Shanghai University, Sixth People's Hospital of Nantong, School of Medicine, Shanghai University, Nantong 226011, China; Cardiac Regeneration and Ageing Lab, Institute of Cardiovascular Sciences, Shanghai Engineering Research Center of Organ Repair, School of Life Science, Shanghai University, Shanghai 200444, China
| | - Lei Wang
- Department of Rehabilitation Medicine, Nanjing University of Chinese Medicine, Nanjing 210023, China
| | - Rongjing Ding
- Department of Cardiology, Peking University People's Hospital, Beijing 100044, China
| | - Lin Che
- Department of Cardiology, Tongji Hospital Affiliated to Tongji University, Tongji University School of Medicine, Shanghai 200065, China
| | - Zhiqing Fan
- Department of Cardiology, Daqing Oilfield General Hospital, Daqing 163000, China
| | - Wei Gao
- Department of Cardiology and Institute of Vascular Medicine, Peking University Third Hospital, NHC Key Laboratory of Cardiovascular Molecular Biology and Regulatory Peptides, Key Laboratory of Molecular Cardiovascular Science, Ministry of Education, Beijing Key Laboratory of Cardiovascular Receptors Research, Beijing 100191, China
| | - Qi Liang
- Department of Rehabilitation Medicine, First Affiliated Hospital of Sun Yat-Sen University, Guangzhou 510080, China
| | - Shenghui Lin
- School of Medicine, Huaqiao University, Quanzhou 362021, China
| | - Suixin Liu
- Division of Cardiac Rehabilitation, Department of Physical Medicine and Rehabilitation, Xiangya Hospital of Central South University, Changsha 410008, China
| | - Xiao Lu
- Department of Rehabilitation Medicine, First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, China
| | - Yuqin Shen
- Department of Cardiology, Tongji Hospital Affiliated to Tongji University, Tongji University School of Medicine, Shanghai 200065, China
| | - Guifu Wu
- Department of Cardiology, Eighth Affiliated Hospital of Sun Yat-Sen University, Shenzhen 518033, China; Guangdong Innovative Engineering and Technology Research Center for Assisted Circulation, Sun Yat-Sen University, Shenzhen 518033, China; NHC Key Laboratory of Assisted Circulation, Sun Yat-Sen University, Guangzhou 510080, China
| | - Jian Yang
- Department of Rehabilitation Medicine, Shanghai Xuhui Central Hospital, Shanghai 200031, China
| | - Guolin Zhang
- Cardiac Rehabilitation Department, Guangdong Cardiovascular Institute, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou 510080, China
| | - Wei Zhao
- Department of Cardiology and Institute of Vascular Medicine, Peking University Third Hospital, NHC Key Laboratory of Cardiovascular Molecular Biology and Regulatory Peptides, Key Laboratory of Molecular Cardiovascular Science, Ministry of Education, Beijing Key Laboratory of Cardiovascular Receptors Research, Beijing 100191, China
| | - Lan Guo
- Cardiac Rehabilitation Department, Guangdong Cardiovascular Institute, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou 510080, China.
| | - Junjie Xiao
- Institute of Geriatrics, Affiliated Nantong Hospital of Shanghai University, Sixth People's Hospital of Nantong, School of Medicine, Shanghai University, Nantong 226011, China; Cardiac Regeneration and Ageing Lab, Institute of Cardiovascular Sciences, Shanghai Engineering Research Center of Organ Repair, School of Life Science, Shanghai University, Shanghai 200444, China.
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Moore K. A Coaching Perspective on Modern Training Metrics and Return from Injury and Illness. Phys Med Rehabil Clin N Am 2021; 33:173-186. [PMID: 34798998 DOI: 10.1016/j.pmr.2021.08.012] [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: 11/25/2022]
Abstract
Guiding cyclists in their return from illness and injury can be managed in many ways. Understanding how cyclists use power-derived training metrics can give care providers a common language to aid in this return. A general understanding of these metrics may be used to monitor cyclists for signs of nonfunctional overreaching or overtraining. Understanding aspects of training and detraining, particularly hematological, is helpful in communicating fitness expectations. Three populations of cyclists are discussed in terms of their expected knowledge of these metrics, typical training volume and intensity, and relationship with a coach or coaches.
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Affiliation(s)
- Kolie Moore
- 132 S Main Street, White River Junction, VT 05001, USA.
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124
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Robin M, Nordez A, Dorel S. Analysis of elite road-cycling sprints in relation to maximal power-velocity-endurance profile: a longitudinal one-case study. Scand J Med Sci Sports 2021; 32:598-611. [PMID: 34800055 DOI: 10.1111/sms.14103] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Revised: 10/11/2021] [Accepted: 11/17/2021] [Indexed: 11/27/2022]
Abstract
The aims of the present study were to characterize the mechanical output of final road sprints of an elite sprinter during international competitions in relation to his power-velocity-endurance characteristics and to investigate the relationship between this sprint performance and the power produced during preceding phases of the race. The sprinter performed a set of short and long sprints (5 to 15-s) on a cycle ergometer to determine his maximal power-velocity-endurance profile. Based on eleven races, the distribution of power throughout each race, peak and mean power (Ppeak and Pmean ) and associated pedaling rates (vPpeak and vPmean ) during the final sprint were analyzed. The power-velocity-endurance profile of the sprinter indicated that his theoeretical mean maximal power and corresponding optimal pedaling rate ranged from 20.0 W.kg-1 (124 rpm) for a 1-s sprint to 15.0 W.kg-1 (109 rpm) for 20 s. Race data showed that final road sprints were mainly performed on the ascending limb of the power-velocity relationship (vPpeak , 104 ± 8 and vPmean , 101 ± 8 rpm). Additionally, Ppeak and Pmean were lower than the theoretical maximal power determined from the power-velocity-endurance profile (9.9 ± 7.0% and 10.6 ± 9.8%, respectively), which highlighted a significant state of fatigue induced by the race. Finally, sprint power exhibited a high variability between races and was strongly related to the level of power produced during the last minute before the sprint. These findings show the importance of considering both the power-velocity-endurance qualities and the power demand of the last lead-up phase before the sprint in order to optimize final sprint performance.
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Affiliation(s)
- Maxime Robin
- Université de Nantes, Movement - Interactions - Performance, MIP, Nantes, EA, 4334, F-44000, France.,TotalEnergies Pro Cycling Team, Essarts-en-Bocage, France
| | - Antoine Nordez
- Université de Nantes, Movement - Interactions - Performance, MIP, Nantes, EA, 4334, F-44000, France.,Faculty of Health and Environmental Sciences, Health and Rehabilitation Research Institute, Auckland University of Technology, Auckland, New Zealand.,Institut Universitaire de France (IUF)
| | - Sylvain Dorel
- Université de Nantes, Movement - Interactions - Performance, MIP, Nantes, EA, 4334, F-44000, France
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125
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Boden BP, Ahmed AE, Fine KM, Craven MJ, Deuster PA. Baseline Aerobic Fitness in High School and College Football Players: Critical for Prescribing Safe Exercise Regimens. Sports Health 2021; 14:490-499. [PMID: 34806472 DOI: 10.1177/19417381211058458] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND Nontraumatic fatalities occur on a regular basis in high school (HS) and college football athletes, primarily in obese linemen performing high-intensity exercise. One contributing factor to these deaths may be a mismatch between baseline aerobic (cardiorespiratory) fitness and exercise regimens. HYPOTHESIS There is a wide range of aerobic fitness in HS and college football players. Body mass index (BMI) is a safe and simple method for estimating baseline aerobic fitness. STUDY DESIGN Retrospective cohort study. LEVEL OF EVIDENCE Level 3. METHODS A retrospective review was performed on 79 HS football athletes who had VO2Peak (mL·kg-1·min-1) measured during the offseason. Multivariate regression analysis was used to determine if BMI (obese, overweight, and normal; kg/m2), position played (linemen vs other), year in school (freshmen vs other), and/or race (African American vs White) were risk factors for poor aerobic fitness. A separate cohort of 135 (48 HS; 87 college) football athletes performed a 6-minute run test to determine speed (miles/min), extrapolate VO2Max, and calculate reference values for suggested upper threshold safe starting speeds (85% of maximum) for aerobic training based on BMI. The relationship between BMI and VO2Peak was assessed. The exercise regimens (speeds) of 2 collegiate football fatalities from the public domain were used to predict their VO2Max values. RESULTS Mean VO2Peak (mL·kg-1·min-1) was 38.5 ± 8.6 (range 19.1-60.6); when grouped by BMI, low scores (<40) were found in 87.5% of obese (32.4 ± 7.7), 47.8% of overweight (40.8 ± 7.6), and 45.2% of normal (41.4 ± 7.8) athletes. VO2Peak was significantly lower in linemen (32.8 ± 6.4; P = 0.007) compared with nonlineman (41.8 ± 7.9), and in obese players (by BMI; 32.4; P = 0.019) compared with nonobese players (41.4 ± 7.6), but did not differ by age, year in school, or race. Means for speed (min/mile) and extrapolated VO2Max (mL·kg-1·min-1) for the 6-minute run test by BMI groups were both significantly different (P = 0.001) for normal (7.0 ± 0.6; 51.1 ± 2.6), overweight (7.6 ± 0.8; 46.5 ± 3.2), and obese (8.9 ± 1.5; 36.8 ± 5.9) athletes. There was a significant negative correlation (r = -0.551; P = 0.001; R2 = 0.304) between VO2Peak and BMI. Safe starting speed recommendations for running 1 mile range from 7.3 to 12.1 min/mile for BMIs 20 to 40 kg/m2 for HS and college athletes. For the 2 fatalities (mean, BMI of 36.5 kg/m2) repetitive sprint speeds were 49 and 89% higher than our safe starting speeds for their BMI. CONCLUSION A large spectrum of baseline aerobic fitness was noted in HS and college football players. Obese players and linemen had statistically lower baseline aerobic fitness, a major risk factor for possible heat illness. BMI is an acceptable surrogate for VO2Peak and can be employed to develop safe training regimens without the need for a maximum fitness test, which can place the athlete at risk for a medical event. CLINICAL RELEVANCE Knowledge of BMI provides an estimate of baseline aerobic fitness and a foundation for prescribing safe, individualized exercise regimens.
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Affiliation(s)
- Barry P Boden
- The Orthopaedic Center, a Division of CAO, Rockville, Maryland
| | - Anwar E Ahmed
- Department of Preventive Medicine and Biostatistics, Uniformed Services University of the Health Sciences, Bethesda, Maryland
| | - Kenneth M Fine
- The Orthopaedic Center, a Division of CAO, Rockville, Maryland
| | | | - Patricia A Deuster
- Consortium for Health and Military Performance, Uniformed Services University of the Health Sciences, Bethesda, Maryland
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Buehler PW, Swindle D, Pak DI, Ferguson SK, Majka SM, Karoor V, Moldovan R, Sintas C, Black J, Gentinetta T, Buzzi RM, Vallelian F, Wassmer A, Edler M, Bain J, Schu D, Hassell K, Nuss R, Schaer DJ, Irwin DC. Hemopexin dosing improves cardiopulmonary dysfunction in murine sickle cell disease. Free Radic Biol Med 2021; 175:95-107. [PMID: 34478834 PMCID: PMC9231663 DOI: 10.1016/j.freeradbiomed.2021.08.238] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Revised: 08/26/2021] [Accepted: 08/29/2021] [Indexed: 01/13/2023]
Abstract
Hemopexin (Hpx) is a crucial defense protein against heme liberated from degraded hemoglobin during hemolysis. High heme stress creates an imbalance in Hpx bioavailability, favoring heme accumulation and downstream pathophysiological responses leading to cardiopulmonary disease progression in sickle cell disease (SCD) patients. Here, we evaluated a model of murine SCD, which was designed to accelerate red blood cell sickling, pulmonary hypertension, right ventricular dysfunction, and exercise intolerance by exposure of the mice to moderate hypobaric hypoxia. The sequence of pathophysiology in this model tracks with circulatory heme accumulation, lipid oxidation, extensive remodeling of the pulmonary vasculature, and fibrosis. We hypothesized that Hpx replacement for an extended period would improve exercise tolerance measured by critical speed as a clinically meaningful therapeutic endpoint. Further, we sought to define the effects of Hpx on upstream cardiopulmonary function, histopathology, and tissue oxidation. Our data shows that tri-weekly administrations of Hpx for three months dose-dependently reduced heme exposure and pulmonary hypertension while improving cardiac pressure-volume relationships and exercise tolerance. Furthermore, Hpx administration dose-dependently attenuated pulmonary fibrosis and oxidative modifications in the lung and myocardium of the right ventricle. Observations in our SCD murine model are consistent with pulmonary vascular and right ventricular pathology at autopsy in SCD patients having suffered from severe pulmonary hypertension, right ventricular dysfunction, and sudden cardiac death. This study provides a translational evaluation supported by a rigorous outcome analysis demonstrating therapeutic proof-of-concept for Hpx replacement in SCD.
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Affiliation(s)
- Paul W Buehler
- University of Maryland, Department of Pathology and the Center for Blood Oxygen Transport, Department of Pediatrics, School of Medicine, Baltimore, MD, USA.
| | - Delaney Swindle
- Cardiovascular and Pulmonary Research Laboratory, Department of Medicine, University of Colorado Denver, Anschutz Medical Campus, Aurora, CO, USA
| | - David I Pak
- Cardiovascular and Pulmonary Research Laboratory, Department of Medicine, University of Colorado Denver, Anschutz Medical Campus, Aurora, CO, USA
| | - Scott K Ferguson
- Cardiovascular and Pulmonary Research Laboratory, Department of Medicine, University of Colorado Denver, Anschutz Medical Campus, Aurora, CO, USA; Department of Kinesiology and Exercise Sciences, College of Natural and Health Sciences, University of Hawaii at Hilo, Hilo, HI, USA
| | - Susan M Majka
- Department of Medicine, Division of Pulmonary, Critical Care and Sleep Medicine, National Jewish Hospital, Denver, CO, USA
| | - Vijaya Karoor
- Cardiovascular and Pulmonary Research Laboratory, Department of Medicine, University of Colorado Denver, Anschutz Medical Campus, Aurora, CO, USA
| | - Radu Moldovan
- Advanced Light Microscopy Core, CU Anschutz Medical Campus, Aurora,, CO, USA
| | - Chantal Sintas
- Department of Pathology and Laboratory Medicine at Children's Hospital Colorado, USA
| | - Jennifer Black
- Department of Pathology, Pediatrics, University of Colorado School of Medicine, USA
| | | | - Raphael M Buzzi
- Division of Internal Medicine, University and University Hospital of Zurich, Zurich, Switzerland
| | - Florence Vallelian
- Division of Internal Medicine, University and University Hospital of Zurich, Zurich, Switzerland
| | | | - Monika Edler
- CSL Behring AG, Research and Development, Bern, Switzerland
| | - Joseph Bain
- CSL Behring AG, Innovations GmbH, Marburg, Germany
| | - Daniel Schu
- CSL Behring AG, Innovations GmbH, Marburg, Germany
| | - Kathryn Hassell
- Division of Hematology Colorado Sickle Cell Treatment and Research Center, School of Medicine, Anschutz Medical Campus, University of Colorado-Denver School of Medicine, Aurora,, CO, USA
| | - Rachelle Nuss
- Division of Hematology Colorado Sickle Cell Treatment and Research Center, School of Medicine, Anschutz Medical Campus, University of Colorado-Denver School of Medicine, Aurora,, CO, USA
| | - Dominik J Schaer
- Division of Internal Medicine, University and University Hospital of Zurich, Zurich, Switzerland
| | - David C Irwin
- Cardiovascular and Pulmonary Research Laboratory, Department of Medicine, University of Colorado Denver, Anschutz Medical Campus, Aurora, CO, USA.
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127
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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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128
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Keir DA, Iannetta D, Mattioni Maturana F, Kowalchuk JM, Murias JM. Identification of Non-Invasive Exercise Thresholds: Methods, Strategies, and an Online App. Sports Med 2021; 52:237-255. [PMID: 34694596 DOI: 10.1007/s40279-021-01581-z] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/03/2021] [Indexed: 10/20/2022]
Abstract
During incremental exercise, two thresholds may be identified from standard gas exchange and ventilatory measurements. The first signifies the onset of blood lactate accumulation (the lactate threshold, LT) and the second the onset of metabolic acidosis (the respiratory compensation point, RCP). The ability to explain why these thresholds occur and how they are identified, non-invasively, from pulmonary gas exchange and ventilatory variables is fundamental to the field of exercise physiology and requisite to the understanding of core concepts including exercise intensity, assessment, prescription, and performance. This review is intended as a unique and comprehensive theoretical and practical resource for instructors, clinicians, researchers, lab technicians, and students at both undergraduate and graduate levels to facilitate the teaching, comprehension, and proper non-invasive identification of exercise thresholds. Specific objectives are to: (1) explain the underlying physiology that produces the LT and RCP; (2) introduce the classic non-invasive measurements by which these thresholds are identified by connecting variable profiles to underlying physiological behaviour; (3) discuss common issues that can obscure threshold detection and strategies to identify and mitigate these challenges; and (4) introduce an online resource to facilitate learning and standard practices. Specific examples of exercise gas exchange and ventilatory data are provided throughout to illustrate these concepts and a novel online application tool designed specifically to identify the estimated LT (θLT) and RCP is introduced. This application is a unique platform for learners to practice skills on real exercise data and for anyone to analyze incremental exercise data for the purpose of identifying θLT and RCP.
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Affiliation(s)
- Daniel A Keir
- School of Kinesiology, The University of Western Ontario, AHB 3G18, 1151 Richmond Street, London, ON, N6A 3K7, Canada. .,Toronto General Research Institute, Toronto General Hospital, Toronto, ON, Canada.
| | - Danilo Iannetta
- Faculty of Kinesiology, University of Calgary, Calgary, AB, Canada
| | | | - John M Kowalchuk
- School of Kinesiology, The University of Western Ontario, AHB 3G18, 1151 Richmond Street, London, ON, N6A 3K7, Canada.,Department of Physiology and Pharmacology, The University of Western Ontario, London, ON, Canada
| | - Juan M Murias
- Faculty of Kinesiology, University of Calgary, Calgary, AB, Canada
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Chartogne M, Leclercq A, Beaune B, Boyas S, Forestier C, Martin T, Thomas-Ollivier V, Landry S, Bourgeois H, Cojocarasu O, Pialoux V, Zanna O, Messonnier LA, Rahmani A, Morel B. Building a biopsychosocial model of cancer-related fatigue: the BIOCARE FActory cohort study protocol. BMC Cancer 2021; 21:1140. [PMID: 34688272 PMCID: PMC8542307 DOI: 10.1186/s12885-021-08831-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Accepted: 10/04/2021] [Indexed: 12/03/2022] Open
Abstract
Background Cancer-related fatigue (CRF) is the most common side effect of cancer and cancer treatment. CRF prevalence is up to 50% in breast cancer patients and can continue several years after cancer remission. This persistent subjective sense of exhaustion is multifactorial. Numerous parameters have been evidenced to be related to CRF across biological, physical, psychological, social and/or behavioral dimensions. Although CRF has been studied for many years, the majority of previous studies focused on only one dimension, i.e., physical function. Moreover, few studies investigated CRF longitudinally with repeated measures. These are the two main obstacles that limit the understanding of CRF mechanisms. The purpose of this study is to create a biopsychosocial model of CRF with simultaneous and longitudinal anthropometric, clinical, biological, physical, psychological and sociological parameters. Methods BIOCARE FActory is a multicentric prospective study that will consist of an 18-month follow-up of 200 women diagnosed with breast cancer. Four visits will be scheduled at diagnosis, after treatments, and 12 and 18 months after diagnosis. The same procedure will be followed for each visit. Each session will be composed of anthropometric data collection, a semi-structured interview, cognitive tests, postural control tests, neuromuscular fatigability tests and a cardiorespiratory fitness test. Clinical and biological data will be collected during medical follow-ups. Participants will also complete questionnaires to assess psychological aspects and quality of life and wear an actigraphy device. Using a structural equation modeling analysis (SEM), collected data will build a biopsychosocial model of CRF, including the physiological, biological, psychological, behavioral and social dimensions of CRF. Discussion This study aims to highlight the dynamics of CRF and its correlates from diagnosis to post treatment. SEM analysis could examine some relations between potential mechanisms and CRF. Thus, the biopsychosocial model will contribute to a better understanding of CRF and its underlying mechanisms from diagnosis to the aftermaths of cancer and its treatments. Trial registration This study is registered at ClinicalTrials.gov (NCT04391543), May 2020.
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Affiliation(s)
- M Chartogne
- Le Mans Université, Movement - Interactions - Performance, MIP, 4334, F-72000, Le Mans, EA, France.
| | - A Leclercq
- Le Mans Université, Movement - Interactions - Performance, MIP, 4334, F-72000, Le Mans, EA, France
| | - B Beaune
- Le Mans Université, Movement - Interactions - Performance, MIP, 4334, F-72000, Le Mans, EA, France
| | - S Boyas
- Le Mans Université, Movement - Interactions - Performance, MIP, 4334, F-72000, Le Mans, EA, France
| | - C Forestier
- Le Mans Université, Movement - Interactions - Performance, MIP, 4334, F-72000, Le Mans, EA, France
| | - T Martin
- Le Mans Université, Movement - Interactions - Performance, MIP, 4334, F-72000, Le Mans, EA, France
| | - V Thomas-Ollivier
- Nantes Université, Movement - Interactions - Performance, MIP, 4334, Nantes, EA, France
| | - S Landry
- Elsan-Clinique Victor Hugo, Centre Jean Bernard, Le Mans, France
| | - H Bourgeois
- Elsan-Clinique Victor Hugo, Centre Jean Bernard, Le Mans, France
| | - O Cojocarasu
- Centre Hospitalier Le Mans (CHM), Le Mans, France
| | - V Pialoux
- Univ Lyon, University Claude Bernard Lyon 1, Inter-University Laboratory of Human Movement Biology, Team Atherosclerosis Thrombosis & Physical Activity, EA7424, Lyon, France
| | - O Zanna
- Le Mans Université, VIPS2, EA4636, Le Mans, France
| | - L A Messonnier
- Laboratoire Interuniversitaire de Biologie de la Motricité, Univ. Savoie Mont Blanc, 7424, F-73000, Chambéry, EA, France
| | - A Rahmani
- Le Mans Université, Movement - Interactions - Performance, MIP, 4334, F-72000, Le Mans, EA, France
| | - B Morel
- Le Mans Université, Movement - Interactions - Performance, MIP, 4334, F-72000, Le Mans, EA, France.,Laboratoire Interuniversitaire de Biologie de la Motricité, Univ. Savoie Mont Blanc, 7424, F-73000, Chambéry, EA, France
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130
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Gorostiaga EM, Sánchez-Medina L, Garcia-Tabar I. Over 55 years of critical power: Fact or artifact? Scand J Med Sci Sports 2021; 32:116-124. [PMID: 34618981 DOI: 10.1111/sms.14074] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Revised: 09/16/2021] [Accepted: 10/04/2021] [Indexed: 11/27/2022]
Abstract
This report aims to generate an evidence-based debate of the Critical Power (CP), or its analogous Critical Speed (CS), concept. Race times of top Spanish runners were utilized to calculate CS based on three (1500-m to 5000-m; CS1.5-5km ) and four (1500-m to 10000-m; CS1.5-10km ) distance performances. Male running world records from 1000 to 5000-m (CS1-5km ), 1000 to 10,000-m (CS1-10km ), 1000-m to half marathon (CS1km-half marathon ), and 1000-m to marathon (CS1km-marathon ) distance races were also utilized for CS calculations. CS1.5-5km (19.62 km h-1 ) and CS1.5-10km (18.68 km h-1 ) were different (p < 0.01), but both approached the average race speed of the longest distance chosen in the model, and were remarkably homogeneous among subjects (97% ±1% and 98% ±1%, respectively). Similar results were obtained using the world records. CS values progressively declined, until reaching a CS1km-marathon value of 20.77 km h-1 (10% lower than CS1-5km ). Each CS value approached the average speed of the longest distance chosen in the model (96.4%-99.8%). A power function better fitted the speed-time relationship compared with the standardized hyperbolic function. However, the horizontal asymptote of a power function is zero. This better approaches the classical definition of CP: the power output that can be maintained almost indefinitely without exhaustion. Beyond any sophisticated mathematical calculation, CS corresponds to 95%-99% of the average speed of the longest distance chosen as an exercise trial. CP could be considered a mathematical artifact rather than an important endurance performance marker. In such a case, the consideration of CP as a physiological "gold-standard" should be reevaluated.
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Affiliation(s)
- Esteban M Gorostiaga
- Studies, Research and Sports Medicine Centre (CEIMD), Government of Navarre, Pamplona, Spain
| | - Luis Sánchez-Medina
- Studies, Research and Sports Medicine Centre (CEIMD), Government of Navarre, Pamplona, Spain
| | - Ibai Garcia-Tabar
- Society, Sports and Physical Exercise Research Group (GIKAFIT), Department of Physical Education and Sport, Faculty of Education and Sport, University of the Basque Country (UPV/EHU), Vitoria-Gasteiz, Spain.,Biobara, GIKAFIT, Vitoria-Gasteiz, Basque Country, Spain
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131
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Follador L, de Borba EF, da Silva SG. Relationship of critical speed derived from a 10-minute submaximal treadmill test to 5-km and 10-km running performances. Appl Physiol Nutr Metab 2021; 47:159-164. [PMID: 34610270 DOI: 10.1139/apnm-2021-0374] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
It has been shown that the critical speed (CS) predicted from a perceptually self-regulated 10-min submaximal treadmill test (T10) is reliable and closely matches the CS estimated from conventional methods. To assess the relationship between the T10 and 5-km and 10-km running performances, 36 recreational runners (mean SD: age: 32.2 ± 6.2 years, height: 173.2 ± 7.3 cm, weight: 70.9 ± 8.8 kg, V̇O2max: 53.3 ± 6.1 mL.kg-1.min-1) performed a ramp incremental test and two T10 tests (the first as a familiarization trial). Results showed that the T10 CS (3.9 ± 0.44 m.s-1) was significantly correlated with runners' last 6 months best performances in 5-km (20.3 ± 2.7 min; r = -0.90) and 10-km (42.7 ± 5.7 min; r = -0.91), the V̇O2max (r = 0.75), the speed associated with the gas exchange threshold (vGET: 3.38 ± 0.36 m.s-1; r = 0.76), the speed associated with the second ventilatory threshold (vVT2: 4.15 ± 0.49 m.s-1; r = 0.84), and the speed associated with the V̇O2max (vV̇O2max: 4.78 ± 0.54 m.s-1; r = 0.87). Moreover, 79% and 83% of the variance in 5-km and 10-km performances could be explained solely by the CS predicted from the T10. Results evidenced the strong relationship and practical performance relevance of the T10 CS test. Novelty: • Critical speed derived from a 10-min submaximal treadmill test (T10) is significantly correlated with 5-km and 10-km running performances • The T10 critical speed test may represent a useful tool for assessing running performance capabilities.
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Affiliation(s)
- Lucio Follador
- Universidade Federal do Parana, 28122, Curitiba, Brazil;
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132
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Abstract
The design of the energy metabolism system in striated muscle remains a major area of investigation. Here, we review our current understanding and emerging hypotheses regarding the metabolic support of muscle contraction. Maintenance of ATP free energy, so called energy homeostasis, via mitochondrial oxidative phosphorylation is critical to sustained contractile activity, and this major design criterion is the focus of this review. Cell volume invested in mitochondria reduces the space available for generating contractile force, and this spatial balance between mitochondria acontractile elements to meet the varying sustained power demands across muscle types is another important design criterion. This is accomplished with remarkably similar mass-specific mitochondrial protein composition across muscle types, implying that it is the organization of mitochondria within the muscle cell that is critical to supporting sustained muscle function. Beyond the production of ATP, ubiquitous distribution of ATPases throughout the muscle requires rapid distribution of potential energy across these large cells. Distribution of potential energy has long been thought to occur primarily through facilitated metabolite diffusion, but recent analysis has questioned the importance of this process under normal physiological conditions. Recent structural and functional studies have supported the hypothesis that the mitochondrial reticulum provides a rapid energy distribution system via the conduction of the mitochondrial membrane potential to maintain metabolic homeostasis during contractile activity. We extensively review this aspect of the energy metabolism design contrasting it with metabolite diffusion models and how mitochondrial structure can play a role in the delivery of energy in the striated muscle.
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Affiliation(s)
- Brian Glancy
- Muscle Energetics Laboratory, National Heart, Lung, and Blood Insititute and National Institute of Arthritis and Musculoskeletal and Skin Disease, Bethesda, Maryland
- Laboratory of Cardiac Energetics, National Heart, Lung, and Blood Insititute, Bethesda, Maryland
| | - Robert S Balaban
- Muscle Energetics Laboratory, National Heart, Lung, and Blood Insititute and National Institute of Arthritis and Musculoskeletal and Skin Disease, Bethesda, Maryland
- Laboratory of Cardiac Energetics, National Heart, Lung, and Blood Insititute, Bethesda, Maryland
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133
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Pinto-Bernal MJ, Cifuentes CA, Perdomo O, Rincón-Roncancio M, Múnera M. A Data-Driven Approach to Physical Fatigue Management Using Wearable Sensors to Classify Four Diagnostic Fatigue States. SENSORS (BASEL, SWITZERLAND) 2021; 21:6401. [PMID: 34640722 PMCID: PMC8513020 DOI: 10.3390/s21196401] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Revised: 09/03/2021] [Accepted: 09/22/2021] [Indexed: 01/02/2023]
Abstract
Physical exercise contributes to the success of rehabilitation programs and rehabilitation processes assisted through social robots. However, the amount and intensity of exercise needed to obtain positive results are unknown. Several considerations must be kept in mind for its implementation in rehabilitation, as monitoring of patients' intensity, which is essential to avoid extreme fatigue conditions, may cause physical and physiological complications. The use of machine learning models has been implemented in fatigue management, but is limited in practice due to the lack of understanding of how an individual's performance deteriorates with fatigue; this can vary based on physical exercise, environment, and the individual's characteristics. As a first step, this paper lays the foundation for a data analytic approach to managing fatigue in walking tasks. The proposed framework establishes the criteria for a feature and machine learning algorithm selection for fatigue management, classifying four fatigue diagnoses states. Based on the proposed framework and the classifier implemented, the random forest model presented the best performance with an average accuracy of ≥98% and F-score of ≥93%. This model was comprised of ≤16 features. In addition, the prediction performance was analyzed by limiting the sensors used from four IMUs to two or even one IMU with an overall performance of ≥88%.
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Affiliation(s)
- Maria J. Pinto-Bernal
- Department of Biomedical Engineering, Colombian School of Engineering Julio Garavito, Bogotá 111166, Colombia; (M.J.P.-B.); (M.M.)
| | - Carlos A. Cifuentes
- Department of Biomedical Engineering, Colombian School of Engineering Julio Garavito, Bogotá 111166, Colombia; (M.J.P.-B.); (M.M.)
| | - Oscar Perdomo
- School of Medicine and Health Sciences, Universidad del Rosario, Bogotá 111711, Colombia;
| | | | - Marcela Múnera
- Department of Biomedical Engineering, Colombian School of Engineering Julio Garavito, Bogotá 111166, Colombia; (M.J.P.-B.); (M.M.)
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134
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Pethick J, Winter SL, Burnley M. Physiological complexity: influence of ageing, disease and neuromuscular fatigue on muscle force and torque fluctuations. Exp Physiol 2021; 106:2046-2059. [PMID: 34472160 DOI: 10.1113/ep089711] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Accepted: 08/26/2021] [Indexed: 11/08/2022]
Abstract
NEW FINDINGS What is the topic of this review? Physiological complexity in muscle force and torque fluctuations, specifically the quantification of complexity, how neuromuscular complexityis altered by perturbations and the potential mechanism underlying changes in neuromuscular complexity. What advances does it highlight? The necessity to calculate both magnitude- and complexity-based measures for the thorough evaluation of force/torque fluctuations. Also the need for further research on neuromuscular complexity, particularly how it relates to the performance of functional activities (e.g. manual dexterity, balance, locomotion). ABSTRACT Physiological time series produce inherently complex fluctuations. In the last 30 years, methods have been developed to characterise these fluctuations, and have revealed that they contain information about the function of the system producing them. Two broad classes of metrics are used: (1) those which quantify the regularity of the signal (e.g. entropy metrics); and (2) those which quantify the fractal properties of the signal (e.g. detrended fluctuation analysis). Using these techniques, it has been demonstrated that ageing results in a loss of complexity in the time series of a multitude of signals, including heart rate, respiration, gait and, crucially, muscle force or torque output. This suggests that as the body ages, physiological systems become less adaptable (i.e. the systems' ability to respond rapidly to a changing external environment is diminished). More recently, it has been shown that neuromuscular fatigue causes a substantial loss of muscle torque complexity, a process that can be observed in a few minutes, rather than the decades it requires for the same system to degrade with ageing. The loss of torque complexity with neuromuscular fatigue appears to occur exclusively above the critical torque (at least for tasks lasting up to 30 min). The loss of torque complexity can be exacerbated with previous exercise of the same limb, and reduced by the administration of caffeine, suggesting both peripheral and central mechanisms contribute to this loss. The mechanisms underpinning the loss of complexity are not known but may be related to altered motor unit behaviour as the muscle fatigues.
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Affiliation(s)
- Jamie Pethick
- School of Sport, Rehabilitation and Exercise Sciences, University of Essex, Colchester, UK
| | - Samantha L Winter
- School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, UK
| | - Mark Burnley
- Endurance Research Group, School of Sport and Exercise Sciences, University of Kent, Chatham Maritime, UK
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135
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Li CC, Chou YJ, Shun SC. The Relationship Between Muscle Strength and Body Composition Measures and Cancer-Related Fatigue: A Systematic Review and Meta-Analysis. Oncol Nurs Forum 2021; 48:558-576. [PMID: 34411084 DOI: 10.1188/21.onf.558-576] [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: 11/17/2022]
Abstract
PROBLEM IDENTIFICATION Cancer-related fatigue (CRF) substantially affects daily living and quality of life, but objective CRF measures remain limited. This review aimed to identify the correlation between muscle strength and body composition measures and CRF, as well as potential objective indicators for assessing CRF. LITERATURE SEARCH PubMed®, MEDLINE®, CINAHL®/PsycINFO®, and Embase® were searched for studies published from January 2000 to January 2021. DATA EVALUATION Study selection and quality assessment were conducted using the Critical Appraisals Skills Programme checklist and the Strengthening the Reporting of Observational Studies in Epidemiology statement. Comprehensive Meta-Analysis software was used to perform meta-analysis. SYNTHESIS 25 studies were selected, and 19 measures were analyzed. CRF negatively correlated with hand grip strength, knee extensor strength, and the sit-to-stand test. No significant correlation was found between body composition measures and CRF. IMPLICATIONS FOR NURSING The evidence suggests that muscle strength measures may be potential indicators for CRF assessment. Combining objective and subjective CRF assessments could assist clinicians in evaluating the effectiveness of CRF interventions more accurately.
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136
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Determining Validity of Critical Power Estimated Using a Three-Minute All-Out Test in Hot Environments. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:ijerph18179193. [PMID: 34501781 PMCID: PMC8431074 DOI: 10.3390/ijerph18179193] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Revised: 08/27/2021] [Accepted: 08/27/2021] [Indexed: 11/21/2022]
Abstract
The aim of this study was to investigate the effects of heat on the validity of end-test power (EP) derived from a 3-min all-out test (3MT), which is considered as an alternative method for determining the conventional critical power. Twelve male cyclists were required to perform incremental exercise tests (IET) and 3MTs in both high temperature (HT; 35 °C) and thermoneutral temperature (NT; 22 °C) environments. Maximal oxygen uptake (VO2max), and first and second ventilatory thresholds (VT1 and VT2, respectively) against the power output (wVO2max, wVT1, and wVT2) were measured during IETs. EP was recorded during the 3MTs. A significant correlation was observed between wVT2 and EP under NT (r = 0.674, p < 0.05) and under HT (r = 0.672, p < 0.05). However, wVO2max, wVT1, wVT2, and EP were significantly higher in NT than in HT (p < 0.05). In conclusion, although the physiological stress induced by HT might impair exercise performance, the EP derived from 3MT can validly estimate wVT2 under HT conditions.
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Nixon RJ, Kranen SH, Vanhatalo A, Jones AM. Steady-state [Formula: see text] above MLSS: evidence that critical speed better represents maximal metabolic steady state in well-trained runners. Eur J Appl Physiol 2021; 121:3133-3144. [PMID: 34351531 PMCID: PMC8505327 DOI: 10.1007/s00421-021-04780-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2021] [Accepted: 07/26/2021] [Indexed: 11/26/2022]
Abstract
The metabolic boundary separating the heavy-intensity and severe-intensity exercise domains is of scientific and practical interest but there is controversy concerning whether the maximal lactate steady state (MLSS) or critical power (synonymous with critical speed, CS) better represents this boundary. We measured the running speeds at MLSS and CS and investigated their ability to discriminate speeds at which \documentclass[12pt]{minimal}
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\begin{document}$$\dot{V}{\text{O}}_{2}$$\end{document}V˙O2 was stable over time from speeds at which a steady-state \documentclass[12pt]{minimal}
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\begin{document}$$\dot{V}{\text{O}}_{2}$$\end{document}V˙O2 could not be established. Ten well-trained male distance runners completed 9–12 constant-speed treadmill tests, including 3–5 runs of up to 30-min duration for the assessment of MLSS and at least 4 runs performed to the limit of tolerance for assessment of CS. The running speeds at CS and MLSS were significantly different (16.4 ± 1.3 vs. 15.2 ± 0.9 km/h, respectively; P < 0.001). Blood lactate concentration was higher and increased with time at a speed 0.5 km/h higher than MLSS compared to MLSS (P < 0.01); however, pulmonary \documentclass[12pt]{minimal}
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\begin{document}$$\dot{V}{\text{O}}_{2}$$\end{document}V˙O2 did not change significantly between 10 and 30 min at either MLSS or MLSS + 0.5 km/h. In contrast, \documentclass[12pt]{minimal}
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\begin{document}$$\dot{V}{\text{O}}_{2}$$\end{document}V˙O2 increased significantly over time and reached \documentclass[12pt]{minimal}
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\begin{document}$$\dot{V}{\text{O}}_{2\,\,\max }$$\end{document}V˙O2max at end-exercise at a speed ~ 0.4 km/h above CS (P < 0.05) but remained stable at a speed ~ 0.5 km/h below CS. The stability of \documentclass[12pt]{minimal}
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\begin{document}$$\dot{V}{\text{O}}_{2}$$\end{document}V˙O2 at a speed exceeding MLSS suggests that MLSS underestimates the maximal metabolic steady state. These results indicate that CS more closely represents the maximal metabolic steady state when the latter is appropriately defined according to the ability to stabilise pulmonary \documentclass[12pt]{minimal}
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\begin{document}$$\dot{V}{\text{O}}_{2}$$\end{document}V˙O2.
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Affiliation(s)
- Rebekah J Nixon
- Sport and Health Sciences, University of Exeter, St. Luke's Campus, Heavitree Road, Exeter, EX12LU, UK
| | - Sascha H Kranen
- Sport and Health Sciences, University of Exeter, St. Luke's Campus, Heavitree Road, Exeter, EX12LU, UK
| | - Anni Vanhatalo
- Sport and Health Sciences, University of Exeter, St. Luke's Campus, Heavitree Road, Exeter, EX12LU, UK
| | - Andrew M Jones
- Sport and Health Sciences, University of Exeter, St. Luke's Campus, Heavitree Road, Exeter, EX12LU, UK.
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Optimization of the Critical Speed Concept for Tactical Professionals: A Brief Review. Sports (Basel) 2021; 9:sports9080106. [PMID: 34437367 PMCID: PMC8402554 DOI: 10.3390/sports9080106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Revised: 06/01/2021] [Accepted: 07/21/2021] [Indexed: 11/16/2022] Open
Abstract
Tactical professionals often depend on their physical ability and fitness to perform and complete occupational tasks to successfully provide public services or survive on the battlefield. Critical speed (CS), or maximal aerobic steady-state, is a purported measure that predicts performance, prescribes exercise, and detects training adaptions with application to tactical professionals. The CS concept has the versatility to adapt to training with load carriage as an integrated bioenergetic system approach for assessment. The aims of this review are to: (1) provide an overview of tactical populations and the CS concept; (2) describe the different methods and equipment used in CS testing; (3) review the literature on CS associated with tactical occupational tasks; and (4) demonstrate the use of CS-derived exercise prescriptions for tactical populations.
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Abstract
Functional Threshold Power (FTP) in cycling is increasingly used in exercise prescription, particularly with the rise in use of home trainers and virtual exercise platforms. FTP testing does not require biological sampling and is considered a more practical test than others. This scoping review investigated what is known about the 20-minute FTP (FTP20) test. A three-step search strategy was used to identify studies in relevant databases (PubMed, CINAHL, SportDiscus, Google Scholar, Web of Science) and grey literature. Data were extracted and common themes identified which allowed for descriptive analysis and thematic summary. Fifteen studies were included. The primary focus fitted broadly into four themes: reliability, association with other physiological markers, other power-related concepts and performance prediction. The FTP20 test was reported as a reliable test. Studies investigating the relationship of FTP20 with other physiological markers and power-related concepts reported large limits of agreement suggesting parameters cannot be used interchangeably. Some findings indicate that FTP20 may be useful in performance prediction. The majority of studies involved trained male cyclists. Overall, existing literature on the FTP20 test is limited. Further investigation is needed to provide physiological justification for FTP20 and inform use in exercise prescription in a range of populations.
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Affiliation(s)
- Jon Mackey
- School of Public Health, Physiotherapy and Sport Science and Institute for Sport and Health, University College Dublin, Dublin, Ireland
| | - Katy Horner
- School of Public Health, Physiotherapy and Sport Science and Institute for Sport and Health, University College Dublin, Dublin, Ireland
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140
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Næss S, Sollie O, Gløersen ØN, Losnegard T. Exercise Intensity and Pacing Pattern During a Cross-Country Olympic Mountain Bike Race. Front Physiol 2021; 12:702415. [PMID: 34349670 PMCID: PMC8326908 DOI: 10.3389/fphys.2021.702415] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Accepted: 06/25/2021] [Indexed: 11/26/2022] Open
Abstract
Objective: To examine the power profiles and pacing patterns in relation to critical power (CP) and maximal aerobic power (MAP) output during a cross-country Olympic (XCO) mountain bike race. Methods: Five male and two female national competitive XCO cyclists completed a UCI Cat. 1 XCO race. The races were 19 km and 23 km and contained five (female) and six (male) laps, respectively. Power output (PO) during the race was measured with the cyclists’ personal power meters. On two laboratory tests using their own bikes and power meters, CP and work capacity above CP (W') were calculated using three time trials of 12, 7, and 3 min, while MAP was established based on a 3-step submaximal test and the maximal oxygen uptake from the 7-min time trial. Results: Mean PO over the race duration (96 ± 7 min) corresponded to 76 ± 9% of CP and 63 ± 4% of MAP. 40 ± 8% of race time was spent with PO > CP, and the mean duration and magnitude of the bouts >CP was ~8 s and ~120% of CP. From the first to last lap, time >CP and accumulated W' per lap decreased with 9 ± 6% and 45 ± 17%, respectively. For single >CP bouts, mean magnitude and mean W' expended decreased by 25 ± 8% and 38 ± 15% from the first to the last lap, respectively. Number and duration of bouts did not change significantly between laps. Conclusion: The highly variable pacing pattern in XCO implies the need for rapid changes in metabolic power output, as a result of numerous separate short-lived >CP actions which decrease in magnitude in later laps, but with little lap-to-lap variation in number and duration.
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Affiliation(s)
- Steffan Næss
- Department of Physical Performance, Norwegian School of Sports Sciences, Oslo, Norway
| | - Ove Sollie
- Department of Physical Performance, Norwegian School of Sports Sciences, Oslo, Norway
| | | | - Thomas Losnegard
- Department of Physical Performance, Norwegian School of Sports Sciences, Oslo, Norway
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141
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Figueiredo DH, Figueiredo DH, Manoel FDA, Machado FA. Peak Running Velocity or Critical Speed Under Field Conditions: Which Best Predicts 5-km Running Performance in Recreational Runners? Front Physiol 2021; 12:680790. [PMID: 34295260 PMCID: PMC8291129 DOI: 10.3389/fphys.2021.680790] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Accepted: 05/26/2021] [Indexed: 12/05/2022] Open
Abstract
This study aimed to examine which variable, between the peak running velocity determined on the track field (Vpeak_TF) and critical speed (CS), is the best predictor of the 5-km running performance in recreational runners. Twenty-five males performed three tests to determine the Vpeak_TF, CS, and 5-km running performance on the track field, with a minimal interval of 48 h between each test. The Vpeak_TF protocol started with a velocity of 8 km⋅h–1, followed by an increase of 1 km⋅h–1 every 3 min until volitional exhaustion, which was controlled by sound signals, with cones at every 25 m indicating when the participants were required to pass the cone’s position to maintain the required velocity. The participants performed three time trials (TTs) (1: 2,600 m; 2: 1,800 m; and 3: 1,000 m) on the same day, with a 30-min rest period to determine the CS through the combinations of three (CS1,2,3) and two TTs (CS1,2, CS1,3, and CS2,3). The 5-km running performance time was recorded to determine the test duration, and the mean velocity (MV) was calculated. There was a significant difference observed between the Vpeak_TF and the MV 5-km running performance. However, no differences were found between the CS values and the MV 5-km running performance. A correlation was observed between the Vpeak_TF (R = −0.90), CS1,2,3 (R = −0.95), CS1,3 (R = −0.95), and the 5-km running performance time. Linear regression indicated that the Vpeak_TF (R2 = 0.82), CS1,2,3 (R2 = 0.90), and CS1,3 (R2 = 0.90) significantly predicted the 5-km running performance time. The CS results showed a higher predictive power for the 5-km running performance, slightly better than the Vpeak_TF. Also, CS1,2,3 and the CS1,3 presented the highest predictive power for the 5-km running performance of recreational runners.
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Affiliation(s)
- Diogo Hilgemberg Figueiredo
- Associate Post-graduate Program in Physical Education, Department of Physical Education, State University of Maringá, Maringá, Brazil
| | - Diego Hilgemberg Figueiredo
- Associate Post-graduate Program in Physical Education, Department of Physical Education, State University of Maringá, Maringá, Brazil
| | | | - Fabiana Andrade Machado
- Associate Post-graduate Program in Physical Education, Department of Physical Education, State University of Maringá, Maringá, Brazil.,Department of Physical Education, State University of Maringá, Maringá, Brazil.,Post-graduate Program of Physiological Sciences, Department of Physiological Sciences, State University of Maringá, Maringá, Brazil
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142
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Johnson MA, Sharpe GR, Needham RS, Williams NC. Effects of Prior Voluntary Hyperventilation on the 3-min All-Out Cycling Test in Men. Med Sci Sports Exerc 2021; 53:1482-1494. [PMID: 33481485 DOI: 10.1249/mss.0000000000002608] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
INTRODUCTION The ergogenic effects of respiratory alkalosis induced by prior voluntary hyperventilation (VH) are controversial. This study examined the effects of prior VH on derived parameters from the 3-min all-out cycling test (3MT). METHODS Eleven men ( = 46 ± 8 mL·kg-1·min-1) performed a 3MT preceded by 15 min of rest (CONT) or VH ( = 38 ± 5 L·min-1) with PETCO2 reduced to 21 ± 1 mm Hg (HYP). End-test power (EP; synonymous with critical power) was calculated as the mean power output over the last 30 s of the 3MT, and the work done above EP (WEP; synonymous with W') was calculated as the power-time integral above EP. RESULTS At the start of the 3MT, capillary blood PCO2 and [H+] were lower in HYP (25.2 ± 3.0 mm Hg, 27.1 ± 2.6 nmol·L-1) than CONT (43.2 ± 2.0 mm Hg, 40.0 ± 1.5 nmol·L-1) (P < 0.001). At the end of the 3MT, blood PCO2 was still lower in HYP (35.7 ± 5.4 mm Hg) than CONT (40.6 ± 5.0 mm Hg) (P < 0.001). WEP was 10% higher in HYP (19.4 ± 7.0 kJ) than CONT (17.6 ± 6.4 kJ) (P = 0.006), whereas EP was 5% lower in HYP (246 ± 69 W) than CONT (260 ± 74 W) (P = 0.007). The ΔWEP (J·kg-1) between CONT and HYP correlated positively with the PCO2 immediately before the 3MT in HYP (r = 0.77, P = 0.006). CONCLUSION These findings suggest that acid-base changes elicited by prior VH increase WEP but decrease EP during the all-out 3MT.
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Affiliation(s)
- Michael A Johnson
- Exercise and Health Research Group, Sport, Health and Performance Enhancement (SHAPE) Research Centre, School of Science and Technology, Nottingham Trent University, Nottingham, UNITED KINGDOM
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143
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Colburn TD, Weber RE, Schulze KM, Sue Hageman K, Horn AG, Behnke BJ, Poole DC, Musch TI. Sexual dimorphism in vascular ATP-sensitive K + channel function supporting interstitial PO2 via convective and/or diffusive O 2 transport. J Physiol 2021; 599:3279-3293. [PMID: 34101850 PMCID: PMC8451062 DOI: 10.1113/jp281120] [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: 11/17/2020] [Accepted: 04/14/2021] [Indexed: 11/08/2022] Open
Abstract
KEY POINTS Inhibition of pancreatic ATP-sensitive K+ (KATP ) channels is the intended effect of oral sulphonylureas to increase insulin release in diabetes. However, pertinent to off-target effects of sulphonylurea medication, sex differences in cardiac KATP channel function exist, whereas potential sex differences in vascular KATP channel function remain unknown. In the present study, we assessed vascular KATP channel function (topical glibenclamide superfused onto fast-twitch oxidative skeletal muscle) supporting blood flow and interstitial O2 delivery-utilization matching ( P O 2 is) during twitch contractions in male, female during pro-oestrus and ovariectomized female (F+OVX) rats. Glibenclamide decreased blood flow (convective O2 transport) and interstitial P O 2 in male and female, but not F+OVX, rats. Compared to males, females also demonstrated impaired diffusive O2 transport and a faster fall in interstitial P O 2 . Our demonstration, in rats, that sex differences in vascular KATP channel function exist support the tentative hypothesis that oral sulphonylureas may exacerbate exercise intolerance and morbidity, especially in premenopausal females. ABSTRACT Vascular ATP-sensitive K+ (KATP ) channels support skeletal muscle blood flow ( Q ̇ m ), interstitial O2 delivery ( Q ̇ O 2 )-utilization ( V ̇ O 2 ) matching (i.e. interstitial-myocyte O2 flux driving pressure; P O 2 is) and exercise tolerance. Potential sex differences in skeletal muscle vascular KATP channel function remain largely unexplored. We hypothesized that local skeletal muscle KATP channel inhibition via glibenclamide superfusion (5 mg kg-1 GLI; sulphonylurea diabetes medication) in anaesthetized female Sprague-Dawley rats, compared to males, would demonstrate greater reductions in contracting (1 Hz, 7 V, 180 s) fast-twitch oxidative mixed gastrocnemius (97% type IIA+IID/X+IIB) Q ̇ m (15 μm microspheres) and P O 2 is (phosphorescence quenching), resulting from more compromised convective ( Q ̇ O 2 ) and diffusive ( D O 2 ) O2 conductances. Furthermore, these GLI-induced reductions in ovary-intact females measured during pro-oestrus would be diminished following ovariectomy (F+OVX). GLI similarly impaired mixed gastrocnemius V ̇ O 2 in both males (↓28%) and females (↓33%, both P < 0.032) via reduced Q ̇ m (male: ↓31%, female: ↓35%, both P < 0.020), Q ̇ O 2 (male: 5.6 ± 0.5 vs. 4.0 ± 0.5, female: 6.4 ± 1.1 vs. 4.2 ± 0.6 mL O2 min-1 100 g tissue-1 , P < 0.022) and the resulting P O 2 is, with females also demonstrating a reduced D O 2 (0.40 ± 0.07 vs. 0.30 ± 0.04 mL O2 min-1 100 g tissue-1 , P < 0.042) and a greater GLI-induced speeding of P O 2 is fall (mean response time: Sex × Drug interaction, P = 0.026). Conversely, GLI did not impair the mixed gastrocnemius of F+OVX rats. Therefore, in patients taking sulphonylureas, these results support the potential for impaired vascular KATP channel function to compromise muscle Q ̇ m and therefore exercise tolerance. Such an effect, if present, would likely contribute to adverse cardiovascular events in premenopausal females more than males.
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Affiliation(s)
- Trenton D. Colburn
- Department of Kinesiology, Physiology, Kansas State University, Manhattan, KS, 66506, USA
| | - Ramona E. Weber
- Department of Kinesiology, Physiology, Kansas State University, Manhattan, KS, 66506, USA
| | - Kiana M. Schulze
- Department of Kinesiology, Physiology, Kansas State University, Manhattan, KS, 66506, USA
| | - K. Sue Hageman
- Department of Anatomy and Physiology, Kansas State University, Manhattan, KS, 66506, USA
| | - Andrew G. Horn
- Department of Kinesiology, Physiology, Kansas State University, Manhattan, KS, 66506, USA
| | - Brad J. Behnke
- Department of Kinesiology, Physiology, Kansas State University, Manhattan, KS, 66506, USA
| | - David C. Poole
- Department of Kinesiology, Physiology, Kansas State University, Manhattan, KS, 66506, USA
- Department of Anatomy and Physiology, Kansas State University, Manhattan, KS, 66506, USA
| | - Timothy I. Musch
- Department of Kinesiology, Physiology, Kansas State University, Manhattan, KS, 66506, USA
- Department of Anatomy and Physiology, Kansas State University, Manhattan, KS, 66506, USA
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144
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Hostrup M, Cairns SP, Bangsbo J. Muscle Ionic Shifts During Exercise: Implications for Fatigue and Exercise Performance. Compr Physiol 2021; 11:1895-1959. [PMID: 34190344 DOI: 10.1002/cphy.c190024] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Exercise causes major shifts in multiple ions (e.g., K+ , Na+ , H+ , lactate- , Ca2+ , and Cl- ) during muscle activity that contributes to development of muscle fatigue. Sarcolemmal processes can be impaired by the trans-sarcolemmal rundown of ion gradients for K+ , Na+ , and Ca2+ during fatiguing exercise, while changes in gradients for Cl- and Cl- conductance may exert either protective or detrimental effects on fatigue. Myocellular H+ accumulation may also contribute to fatigue development by lowering glycolytic rate and has been shown to act synergistically with inorganic phosphate (Pi) to compromise cross-bridge function. In addition, sarcoplasmic reticulum Ca2+ release function is severely affected by fatiguing exercise. Skeletal muscle has a multitude of ion transport systems that counter exercise-related ionic shifts of which the Na+ /K+ -ATPase is of major importance. Metabolic perturbations occurring during exercise can exacerbate trans-sarcolemmal ionic shifts, in particular for K+ and Cl- , respectively via metabolic regulation of the ATP-sensitive K+ channel (KATP ) and the chloride channel isoform 1 (ClC-1). Ion transport systems are highly adaptable to exercise training resulting in an enhanced ability to counter ionic disturbances to delay fatigue and improve exercise performance. In this article, we discuss (i) the ionic shifts occurring during exercise, (ii) the role of ion transport systems in skeletal muscle for ionic regulation, (iii) how ionic disturbances affect sarcolemmal processes and muscle fatigue, (iv) how metabolic perturbations exacerbate ionic shifts during exercise, and (v) how pharmacological manipulation and exercise training regulate ion transport systems to influence exercise performance in humans. © 2021 American Physiological Society. Compr Physiol 11:1895-1959, 2021.
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Affiliation(s)
- Morten Hostrup
- Section of Integrative Physiology, Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark
| | - Simeon Peter Cairns
- SPRINZ, School of Sport and Recreation, Auckland University of Technology, Auckland, New Zealand.,Health and Rehabilitation Research Institute, Auckland University of Technology, Auckland, New Zealand
| | - Jens Bangsbo
- Section of Integrative Physiology, Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark
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145
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Nascimento EMF, do Nascimento Salvador PC, Antunes D, Possamai LT, Ventura T, Guglielmo LGA, Denadai BS, de Lucas RD. Heart rate variability kinetics during different intensity domains of cycling exercise in healthy subjects. Eur J Sport Sci 2021; 22:1231-1239. [PMID: 34077297 DOI: 10.1080/17461391.2021.1938689] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
The purpose of this study was to verify the heart rate variability (HRV) and heart rate (HR) kinetics during the fundamental phase in different intensity domains of cycling exercise. Fourteen males performed five exercise sessions: (1) maximal incremental cycling test; (2) two rest-to-exercise transitions for each intensity domain, that is, heavy (Δ30) and severe (Δ60) domains. HRV markers (SD1 and SD2) and HR kinetics in the fundamental phase were analyzed by first-order exponential fitting. There were no significant differences in amplitude values between SD1Δ30 (8.98 ± 3.52 ms) and SD1Δ60 (9.44 ± 3.24 ms) and SD2Δ30 (24.93 ± 9.16 ms) and SD2Δ60 (25.98 ± 7.29 ms). Significant difference was observed between HRΔ30 (52 ± 7 bpm) and HRΔ60 (63 ± 8 bpm). The time constant (τ) values were significantly different between SD1Δ30 (17.61 ± 6.26 s) and SD1Δ60 (13.86 ± 5.90 s), but not between SD2Δ30 (20.06 ± 3.73 s) and SD2Δ60 (19.47 ± 6.03 s) or HRΔ30 (56.75 ± 18.22 s) and HRΔ60 (58.49 ± 15.61 s). However, the τ values for HRΔ30 were higher and significantly different in relation to SD1Δ30 and SD2Δ30, as well as for HRΔ60 in relation to SD1Δ60 and SD2Δ60. The kinetics of the autonomic variable (SD1 marker) was accelerated by the increased intensity. Moreover, significant differences were found for the τ values, with faster HRV markers than HR, in both intensities of Δ30 and Δ60, which suggests that these variables indicate distinct and specific cardiac autonomic response times during different intensity domains in cycling.HIGHLIGHTS The application of HRV to optimize exercise prescription at different effort intensities is extremely important to obtain assertive and effective results.Analysis of the kinetic responses of HRV is a useful tool for the evaluation of exercise performance and health status.A faster kinetics was found for HRV markers in comparison to HR, for both intensities analysed, which suggests that these variables indicate distinct and specific cardiac autonomic response times during different intensity domains in cycling.
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Affiliation(s)
| | | | - Diego Antunes
- Physical Effort Laboratory, Sports Center, Federal University of Santa Catarina, Florianópolis, Brazil
| | | | - Thiago Ventura
- Physical Effort Laboratory, Sports Center, Federal University of Santa Catarina, Florianópolis, Brazil
| | | | - Benedito Sérgio Denadai
- Physical Effort Laboratory, Sports Center, Federal University of Santa Catarina, Florianópolis, Brazil.,Human Performance Laboratory, São Paulo State University, Rio Claro, Brazil
| | - Ricardo Dantas de Lucas
- Physical Effort Laboratory, Sports Center, Federal University of Santa Catarina, Florianópolis, Brazil
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146
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The ramp and all-out exercise test to determine critical power: validity and robustness to manipulations in body position. Eur J Appl Physiol 2021; 121:2721-2730. [PMID: 34143306 PMCID: PMC8416884 DOI: 10.1007/s00421-021-04739-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2021] [Accepted: 06/08/2021] [Indexed: 11/20/2022]
Abstract
Purpose The purpose of the present study was to determine whether a contiguous ramp and all-out exercise test could accurately determine critical power (CP) in a single laboratory visit during both upright and supine cycle exercise. Methods Healthy males completed maximal ramp-incremental exercise on a cycle ergometer in the upright (n = 15) and supine positions (n = 8), with task failure immediately followed by a 3-min all-out phase for determination of end-test power (EP). On separate days, participants undertook four constant-power tests in either the upright or supine positions with the limit of tolerance ranging from ~ 2 to 15 min for determination of CP. Results During upright exercise, EP was highly correlated with (R2 = 0.93, P < 0.001) and not different from CP (CP = 221 ± 40 W vs. EP = 226 ± 46 W, P = 0.085, 95% limits of agreement − 30, 19 W). During supine exercise, EP was also highly correlated with (R2 = 0.94, P < 0.001) and not different from CP (CP = 140 ± 42 W vs. EP = 136 ± 40 W, P = 0.293, 95% limits of agreement − 16, 24 W). Conclusion The present data suggest that EP derived from a contiguous ramp all-out exercise test is not different from the gold-standard method of CP determination during both upright and supine cycle exercise when assessed at the group level. However, the wide limits of agreement observed within the present study suggest that EP and CP should not be used interchangeably.
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147
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Influence of muscular contraction on vascular conductance during exercise above versus below critical power. Respir Physiol Neurobiol 2021; 293:103718. [PMID: 34126260 DOI: 10.1016/j.resp.2021.103718] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Revised: 06/02/2021] [Accepted: 06/08/2021] [Indexed: 11/20/2022]
Abstract
We tested the hypothesis that limb vascular conductance (LVC) would increase during the immediate recovery phase of dynamic exercise above, but not below, critical power (CP) indicating a threshold for muscular contraction-induced impedance of limb blood flow (LBF). CP (115 ± 26 W) was determined in 7 men and 7 women who subsequently performed ∼5 min of near-supine cycling exercise both below and above CP. LVC demonstrated a greater increase during immediate recovery and remained significantly higher following exercise above, compared to below, CP (all p < 0.001). Power output was associated with the immediate increases in LVC following exercise above, but not below, CP (p < 0.001; r = 0.85). Additionally, variance in percent LBF impedance was significantly lower above (CV: 10.7 %), compared to below (CV: 53.2 %), CP (p < 0.01). CP appears to represent a threshold above which the characteristics of LBF impedance by muscular contraction become intensity-dependent. These data suggest a critical level of LBF impedance relative to contraction intensity exists and, once attained, may promote the progressive metabolic and neuromuscular responses known to occur above CP.
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Valenzuela PL, Alejo LB, Montalvo-Pérez A, Gil-Cabrera J, Talavera E, Lucia A, Barranco-Gil D. Relationship Between Critical Power and Different Lactate Threshold Markers in Recreational Cyclists. Front Physiol 2021; 12:676484. [PMID: 34177619 PMCID: PMC8220144 DOI: 10.3389/fphys.2021.676484] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Accepted: 05/12/2021] [Indexed: 11/17/2022] Open
Abstract
Purpose: To analyze the relationship between critical power (CP) and different lactate threshold (LT2) markers in cyclists. Methods: Seventeen male recreational cyclists [33 ± 5 years, peak power output (PO) = 4.5 ± 0.7 W/kg] were included in the study. The PO associated with four different fixed (onset of blood lactate accumulation) and individualized (Dmaxexp, Dmaxpol, and LTΔ1) LT2 markers was determined during a maximal incremental cycling test, and CP was calculated from three trials of 1-, 5-, and 20-min duration. The relationship and agreement between each LT2 marker and CP were then analyzed. Results: Strong correlations (r = 0.81–0.98 for all markers) and trivial-to-small non-significant differences (Hedges’ g = 0.01–0.17, bias = 1–9 W, and p > 0.05) were found between all LT2 markers and CP with the exception of Dmaxexp, which showed the strongest correlation but was slightly higher than the CP (Hedges’ g = 0.43, bias = 20 W, and p < 0.001). Wide limits of agreement (LoA) were, however, found for all LT2 markers compared with CP (from ±22 W for Dmaxexp to ±52 W for Dmaxpol), and unclear to most likely practically meaningful differences (PO differences between markers >1%, albeit <5%) were found between markers attending to magnitude-based inferences. Conclusion: LT2 markers show a strong association and overall trivial-to-small differences with CP. Nevertheless, given the wide LoA and the likelihood of potentially meaningful differences between these endurance-related markers, caution should be employed when using them interchangeably.
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Affiliation(s)
- Pedro L Valenzuela
- Faculty of Sport Sciences, Universidad Europea de Madrid, Madrid, Spain.,Physical Activity and Health Laboratory, Instituto de Investigación Sanitaria Hospital '12 de Octubre' ('imas12'), Madrid, Spain
| | - Lidia B Alejo
- Faculty of Sport Sciences, Universidad Europea de Madrid, Madrid, Spain.,Physical Activity and Health Laboratory, Instituto de Investigación Sanitaria Hospital '12 de Octubre' ('imas12'), Madrid, Spain
| | | | - Jaime Gil-Cabrera
- Faculty of Sport Sciences, Universidad Europea de Madrid, Madrid, Spain
| | - Eduardo Talavera
- Faculty of Sport Sciences, Universidad Europea de Madrid, Madrid, Spain
| | - Alejandro Lucia
- Faculty of Sport Sciences, Universidad Europea de Madrid, Madrid, Spain.,Physical Activity and Health Laboratory, Instituto de Investigación Sanitaria Hospital '12 de Octubre' ('imas12'), Madrid, Spain
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149
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Meyler S, Bottoms L, Muniz-Pumares D. Biological and methodological factors affecting V ̇ O 2 max response variability to endurance training and the influence of exercise intensity prescription. Exp Physiol 2021; 106:1410-1424. [PMID: 34036650 DOI: 10.1113/ep089565] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Accepted: 05/07/2021] [Indexed: 12/21/2022]
Abstract
NEW FINDINGS What is the topic of this review? Biological and methodological factors associated with the variable changes in cardiorespiratory fitness in response to endurance training. What advances does it highlight? Several biological and methodological factors exist that each contribute, to a given extent, to response variability. Notably, prescribing exercise intensity relative to physiological thresholds reportedly increases cardiorespiratory fitness response rates compared to when prescribed relative to maximum physiological values. As threshold-based approaches elicit more homogeneous acute physiological responses among individuals, when repeated over time, these uniform responses may manifest as more homogeneous chronic adaptations thereby reducing response variability. ABSTRACT Changes in cardiorespiratory fitness (CRF) in response to endurance training (ET) exhibit large variations, possibly due to a multitude of biological and methodological factors. It is acknowledged that ∼20% of individuals may not achieve meaningful increases in CRF in response to ET. Genetics, the most potent biological contributor, has been shown to explain ∼50% of response variability, whilst age, sex and baseline CRF appear to explain a smaller proportion. Methodological factors represent the characteristics of the ET itself, including the type, volume and intensity of exercise, as well as the method used to prescribe and control exercise intensity. Notably, methodological factors are modifiable and, upon manipulation, alter response rates to ET, eliciting increases in CRF regardless of an individual's biological predisposition. Particularly, prescribing exercise intensity relative to a physiological threshold (e.g., ventilatory threshold) is shown to increase CRF response rates compared to when intensity is anchored relative to a maximum physiological value (e.g., maximum heart rate). It is, however, uncertain whether the increased response rates are primarily attributable to reduced response variability, greater mean changes in CRF or both. Future research is warranted to elucidate whether more homogeneous chronic adaptations manifest over time among individuals, as a result of exposure to more homogeneous exercise stimuli elicited by threshold-based practices.
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Affiliation(s)
- Samuel Meyler
- School of Life and Medical Sciences, University of Hertfordshire, Hatfield, UK
| | - Lindsay Bottoms
- School of Life and Medical Sciences, University of Hertfordshire, Hatfield, UK
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150
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Vassallo C, Kilduff LP, Cummins C, Murphy A, Gray A, Waldron M. A new energetics model for the assessment of the power-duration relationship during over-ground running. Eur J Sport Sci 2021; 22:1211-1221. [PMID: 33993836 DOI: 10.1080/17461391.2021.1931463] [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: 10/21/2022]
Abstract
We evaluated the reliability of an over-ground running three-minute all-out test (3MT) and compared this to traditional multiple-visit testing to determine the critical speed (CS) and distance > CS (D´). Using a novel energetics model during the 3MT, critical power (CP) and work > CP (W´) were also evaluated for reliability and compared to the multiple-visit tests. Over-ground running speed was measured using Global Positioning Systems during fixed-speed trials on a 400 m track to exhaustion, at four intensities corresponding to: (i) maximal oxygen uptake (V˙O2max) (Vmax), (ii) 110% V˙O2max(110%Vmax), (iii) Δ70% (i.e. 70% of the difference between gas exchange threshold and Vmax) and (iv) Δ85%. The participants subsequently performed the 3MT across two days to determine its reliability. There were no differences between the multiple-visit testing and the 3MT for CS (P = 0.328) and D´ (P = 0.919); however, CP (P = 0.02) and W´ (P < 0.001) were higher in the 3MT. The reliability of the 3MT was stable (P > 0.05) between trials for all variables, with coefficient of variation ranging from 2.0-8.1%. The current over-ground energetics model can reliably estimate CP and W´ based on GPS speed data during the 3MT, which supports its use for most athletic training and monitoring purposes. The reliability of the over-ground running 3MT for power- and speed-related indices was sufficient to detect typical training adaptations; however, it may overestimate CP (∼ 25 W) and W´ (∼ 7 kJ) compared to multiple-visit tests.
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Affiliation(s)
| | - Liam P Kilduff
- A-STEM, College of Engineering, Swansea University, Swansea, UK.,Welsh Institute of Performance Science, Swansea University, Swansea, UK
| | - Cloe Cummins
- School of Science and Technology, University of New England, Australia.,Carnegie Applied Rugby Research (CARR) centre, Institute for Sport Physical Activity and Leisure, Leeds Beckett University, Leeds, United Kingdom.,National Rugby League, Australia
| | - Aron Murphy
- School of Science and Technology, University of New England, Australia
| | - Adrian Gray
- School of Science and Technology, University of New England, Australia
| | - Mark Waldron
- A-STEM, College of Engineering, Swansea University, Swansea, UK.,School of Science and Technology, University of New England, Australia.,Welsh Institute of Performance Science, Swansea University, Swansea, UK
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