1
|
Fennell CRJ, Mauger AR, Hopker JG. Inter-day reliability of heart rate complexity and variability metrics in healthy highly active younger and older adults. Eur J Appl Physiol 2024; 124:1409-1424. [PMID: 38054978 PMCID: PMC11055755 DOI: 10.1007/s00421-023-05373-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Accepted: 11/11/2023] [Indexed: 12/07/2023]
Abstract
PURPOSE To investigate the inter-day reliability of time-domain, frequency-domain, and nonlinear HRV metrics in healthy highly active younger and older adults. The study also assessed the effect of age on the HRV metrics. METHODS Forty-four older adults (34 M, 10F; 59 ± 5 years;V ˙ O 2peak = 40.9 ± 7.6 ml kg-1 min-1) and twenty-two younger adults (16 M, 6F; 22 ± 4 years;V ˙ O 2peak = 47.2 ± 12.8 ml kg-1 min-1) attended the laboratory. Visit one assessed aerobic fitness through an exercise test. In visits two and three, participants completed a 30-min supine RR interval measurement to derive the HRV metrics. RESULTS The younger group (YG) and older group (OG) demonstrated poor to good day-to-day relative and absolute reliability for all HRV metrics (OG, ICCs = 0.33 to 0.69 and between day CVs = 3.8 to 29.2%; YG, ICCs = 0.37 to 0.93 and between day CVs = 3.5 to 36.5%). There was a significant reduction in ApEn (P < 0.001), SampEn (P = 0.031), RMSSD (P < 0.001), SDNN (P < 0.001), LF power (P < 0.001) and HF power (P < 0.001), HRV metrics with ageing. There was no significant effect of age the complexity metrics DFA α1 (P = 0.107), α2 (P = 0.147) and CI-8 (P = 0.493). CONCLUSION HRV metrics are reproducible between days in both healthy highly active younger and older adults. There is a decline in linear and nonlinear HRV metrics with age, albeit there being no age-related change in the nonlinear metrics, DFA α1, α2 and CI-8.
Collapse
Affiliation(s)
- Christopher R J Fennell
- School of Sport and Exercise Sciences, University of Kent, Chipperfield Building, Canterbury, Kent, CT2 7PE, UK.
| | - Alexis R Mauger
- School of Sport and Exercise Sciences, University of Kent, Chipperfield Building, Canterbury, Kent, CT2 7PE, UK
| | - James G Hopker
- School of Sport and Exercise Sciences, University of Kent, Chipperfield Building, Canterbury, Kent, CT2 7PE, UK
| |
Collapse
|
2
|
Dotan R, Woods S, Langille J, Falk B. Boys-men mean-power-frequency differences in progressive exercise to exhaustion, confounded by variability and adiposity. Eur J Appl Physiol 2024; 124:491-505. [PMID: 37553549 DOI: 10.1007/s00421-023-05292-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2023] [Accepted: 07/26/2023] [Indexed: 08/10/2023]
Abstract
BACKGROUND Only scant research has compared children's mean power frequency (MPF) to adults', with a clear overview still lacking. A significant obstacle has been MPF's high variability, which this study aimed to overcome by elucidating the MPF characteristics distinguishing boys from men in progressive exhaustive exercise. METHODS Electromyographic (EMG) data of 20 men (23.5 ± 2.5yrs) and 17 boys (10.2 ± 1.0 yrs), who performed progressively exhausting, intermittent isometric knee extensions, were subjected to secondary MPF analysis. Participants' vastus lateralis MPF data series were transformed to third-order polynomial regressions and expressed as percentages of the peak polynomial MPF values (%MPFpeak). The resulting curves were compared at 5-% time-to-exhaustion (TTE) intervals, using repeated-measures ANOVA. Raw MPFpeak values were adiposity corrected to 0% fat and used to convert the %MPFpeak data back to absolute MPF values (Hz) for estimating muscle-level MPF. RESULTS No overall interaction or group effects could be shown between the %MPFpeak plots, but pairwise comparisons revealed significantly higher men's values at 50-70%TTE and lower at 100%TTE, i.e. boys' shallower MPF rise and decline. The adiposity-corrected boys' and men's composite MPF values peaked at 125.7 ± 2.5 and 166.0 ± 2.4 Hz, respectively (110.7 ± 1.7 and 122.5 ± 2.1 Hz, uncorrected), with a significant group effect (p < 0.05) and pairwise differences at all %TTE points. CONCLUSIONS The boys were lower than the men in both the observed and, more so, in the adiposity-corrected MPF values that presumably estimate muscle-level MPF. The boys' shallower MPF rise and decline conform to children's claimed type-II motor-unit activation and/or compositional deficits and their related known advantage in muscular endurance.
Collapse
Affiliation(s)
- Raffy Dotan
- Kinesiology Department, Faculty of Applied Health Sciences, Brock University, St Catharines, ON, Canada.
| | - Stacey Woods
- Kinesiology Department, Faculty of Applied Health Sciences, Brock University, St Catharines, ON, Canada
| | - Jordan Langille
- Kinesiology Department, Faculty of Applied Health Sciences, Brock University, St Catharines, ON, Canada
| | - Bareket Falk
- Kinesiology Department, Faculty of Applied Health Sciences, Brock University, St Catharines, ON, Canada
| |
Collapse
|
3
|
Rosenblat MA, Arnold J, Nelson H, Watt J, Seiler S. The Additional Effect of Training Above the Maximal Metabolic Steady State on VO2peak, Wpeak and Time-Trial Performance in Endurance-Trained Athletes: A Systematic Review, Meta-analysis, and Reality Check. Sports Med 2024; 54:429-446. [PMID: 37737543 DOI: 10.1007/s40279-023-01924-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/21/2023] [Indexed: 09/23/2023]
Abstract
BACKGROUND To improve sport performance, athletes use training regimens that include exercise below and above the maximal metabolic steady state (MMSS). OBJECTIVE The objective of this review was to determine the additional effect of training above MMSS on VO2peak, Wpeak and time-trial (TT) performance in endurance-trained athletes. METHODS Studies were included in the review if they (i) were published in academic journals, (ii) were in English, (iii) were prospective, (iv) included trained participants, (v) had an intervention group that contained training above and below MMSS, (vi) had a comparator group that only performed training below MMSS, and (vii) reported results for VO2peak, Wpeak, or TT performance. Medline and SPORTDiscus were searched from inception until February 23, 2023. RESULTS Fourteen studies that ranged from 2 to 12 weeks were included in the review. There were 171 recreational and 128 competitive endurance athletes. The mean age and VO2peak of participants ranged from 15 to 43 years and 38 to 68 mL·kg-1·min-1, respectively. The inclusion of training above MMSS led to a 2.5 mL·kg-1·min-1 (95% CI 1.4-3.6; p < 0.01; I2 = 0%) greater improvement in VO2peak. A minimum of 81 participants per group would be required to obtain sufficient power to determine a significant effect (SMD 0.44) for VO2peak. No intensity-specific effect was observed for Wpeak or TT performance, in part due to a smaller sample size. CONCLUSION A single training meso-cycle that includes training above MMSS can improve VO2peak in endurance-trained athletes more than training only below MMSS. However, we do not have sufficient evidence to conclude that concurrent adaptation occurs for Wpeak or TT performance.
Collapse
Affiliation(s)
| | - Jem Arnold
- School of Kinesiology, Faculty of Education, University of British Columbia, Vancouver, BC, Canada
| | - Hannah Nelson
- Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC, Canada
| | - Jennifer Watt
- Knowledge Translation Program, Li Ka Shing Knowledge Institute, St Michael's Hospital, Toronto, ON, Canada
- Division of Geriatric Medicine, Department of Medicine, University of Toronto, Toronto, ON, Canada
- Institute of Health Policy, Management and Evaluation, Dalla Lana School of Public Health, University of Toronto, Toronto, ON, Canada
| | - Stephen Seiler
- Department of Sport Science and Physical Education, Faculty of Health and Sport Sciences, University of Agder, Kristiansand, Norway
| |
Collapse
|
4
|
Giampaoli O, Ieno C, Sciubba F, Spagnoli M, Miccheli A, Tomassini A, Aureli W, Fattorini L. Metabolic Biomarkers of Red Beetroot Juice Intake at Rest and after Physical Exercise. Nutrients 2023; 15:2026. [PMID: 37432172 DOI: 10.3390/nu15092026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2023] [Revised: 04/20/2023] [Accepted: 04/20/2023] [Indexed: 07/12/2023] Open
Abstract
BACKGROUND Red beetroot is known to be a health-promoting food. However, little attention is placed on intestinal bioactive compound absorption. The aim of the study was to assess the urinary red beetroot juice (RBJ) intake biomarkers and possible differences in RBJ's micronutrient absorption at rest or after physical exercise. METHODS This is a three-armed, single-blind study, involving seven healthy volunteers which were randomly divided into three groups and alternatively assigned to three experimental sessions: RBJ intake at rest, RBJ intake with physical activity, and placebo intake with physical activity. For each session, urine samples were collected before and 120, 180, and 240 min after the intake of RBJ or placebo. The same sampling times were employed for the experimental session at rest. The RBJ metabolic composition was also characterized to identify the urinary biomarkers derived from the intake. RESULTS 4-methylpyridine-2-carboxylic acid, dopamine-3-O-sulfate, glutamine, and 3-hydroxyisobutyrate were identified as RBJ intake biomarkers. Physical activity significantly increased only the dopamine-3-O-sulfate excretion 120 min after RBJ intake. CONCLUSIONS Urinary dopamine-3-O-sulfate is related to RBJ dopamine content, while 4-methylpyridine-2-carboxylic acid is a betanin or betalamic acid catabolite. The different excretions of these metabolites following physical activity suggest a possible effect on the RBJ uptake depending on different transport processes through the mucosa, namely diffusion-mediated transport for dopamine and saturable transcellular transport for betalamic acid derivatives. These results open new perspectives in improving the absorption of natural bioactive molecules through physical activity.
Collapse
Affiliation(s)
- Ottavia Giampaoli
- NMR-Based Metabolomics Laboratory (NMLab), Sapienza University of Rome, 00185 Rome, Italy
- Department of Environmental Biology, Sapienza University of Rome, 00185 Rome, Italy
| | - Cristian Ieno
- Department of Physiology and Pharmacology "Vittorio Erspamer", Sapienza University of Rome, 00185 Rome, Italy
| | - Fabio Sciubba
- NMR-Based Metabolomics Laboratory (NMLab), Sapienza University of Rome, 00185 Rome, Italy
- Department of Environmental Biology, Sapienza University of Rome, 00185 Rome, Italy
| | - Mariangela Spagnoli
- NMR-Based Metabolomics Laboratory (NMLab), Sapienza University of Rome, 00185 Rome, Italy
- Department of Occupational Medicine, Epidemiology and Hygiene, INAIL, Monte Porzio Catone, 00078 Rome, Italy
| | - Alfredo Miccheli
- NMR-Based Metabolomics Laboratory (NMLab), Sapienza University of Rome, 00185 Rome, Italy
- Department of Environmental Biology, Sapienza University of Rome, 00185 Rome, Italy
| | - Alberta Tomassini
- R&D Aureli Mario S. S. Agricola, Via Mario Aureli 7, 67050 Ortucchio, Italy
| | - Walter Aureli
- R&D Aureli Mario S. S. Agricola, Via Mario Aureli 7, 67050 Ortucchio, Italy
| | - Luigi Fattorini
- Department of Physiology and Pharmacology "Vittorio Erspamer", Sapienza University of Rome, 00185 Rome, Italy
| |
Collapse
|
5
|
Römer C, Wolfarth B. Prediction of Relevant Training Control Parameters at Individual Anaerobic Threshold without Blood Lactate Measurement. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2023; 20:4641. [PMID: 36901647 PMCID: PMC10001845 DOI: 10.3390/ijerph20054641] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Revised: 02/24/2023] [Accepted: 02/28/2023] [Indexed: 06/18/2023]
Abstract
BACKGROUND Active exercise therapy plays an essential role in tackling the global burden of obesity. Optimizing recommendations in individual training therapy requires that the essential parameters heart rate HR(IAT) and work load (W/kg(IAT) at individual anaerobic threshold (IAT) are known. Performance diagnostics with blood lactate is one of the most established methods for these kinds of diagnostics, yet it is also time consuming and expensive. METHODS To establish a regression model which allows HR(IAT) and (W/kg(IAT) to be predicted without measuring blood lactate, a total of 1234 performance protocols with blood lactate in cycle ergometry were analyzed. Multiple linear regression analyses were performed to predict the essential parameters (HR(IAT)) (W/kg(IAT)) by using routine parameters for ergometry without blood lactate. RESULTS HR(IAT) can be predicted with an RMSE of 8.77 bpm (p < 0.001), R2 = 0.799 (|R| = 0.798) without performing blood lactate diagnostics during cycle ergometry. In addition, it is possible to predict W/kg(IAT) with an RMSE (root mean square error) of 0.241 W/kg (p < 0.001), R2 = 0.897 (|R| = 0.897). CONCLUSIONS It is possible to predict essential parameters for training management without measuring blood lactate. This model can easily be used in preventive medicine and results in an inexpensive yet better training management of the general population, which is essential for public health.
Collapse
|
6
|
Festa RR, Monsalves-Álvarez M, Cancino J, Jannas-Vela S. Prescription of High-intensity Aerobic Interval Training Based on Oxygen Uptake Kinetics. Int J Sports Med 2023; 44:159-168. [PMID: 35995143 DOI: 10.1055/a-1929-0295] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Endurance training results in diverse adaptations that lead to increased performance and health benefits. A commonly measured training response is the analysis of oxygen uptake kinetics, representing the demand of a determined load (speed/work) on the cardiovascular, respiratory, and metabolic systems, providing useful information for the prescription of constant load or interval-type aerobic exercise. There is evidence that during high-intensity aerobic exercise some interventions prescribe brief interval times (<1-min), which may lead to a dissociation between the load prescribed and the oxygen uptake demanded, potentially affecting training outcomes. Therefore, this review explored the time to achieve a close association between the speed/work prescribed and the oxygen uptake demanded after the onset of high-intensity aerobic exercise. The evidence assessed revealed that at least 80% of the oxygen uptake amplitude is reached when phase II of oxygen uptake kinetics is completed (1 to 2 minutes after the onset of exercise, depending on the training status). We propose that the minimum work-time during high-intensity aerobic interval training sessions should be at least 1 minute for athletes and 2 minutes for non-athletes. This suggestion could be used by coaches, physical trainers, clinicians and sports or health scientists for the prescription of high-intensity aerobic interval training.
Collapse
Affiliation(s)
- Raúl Ricardo Festa
- Laboratorio de Fisiología del Ejercicio y Metabolismo, Escuela de Kinesiología, Universidad Finis Terrae, Santiago, Chile
| | | | - Jorge Cancino
- Laboratorio de Fisiología del Ejercicio y Metabolismo, Escuela de Kinesiología, Universidad Finis Terrae, Santiago, Chile
| | | |
Collapse
|
7
|
Does Beetroot Supplementation Improve Performance in Combat Sports Athletes? A Systematic Review of Randomized Controlled Trials. Nutrients 2023; 15:nu15020398. [PMID: 36678270 PMCID: PMC9860842 DOI: 10.3390/nu15020398] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2022] [Revised: 01/10/2023] [Accepted: 01/11/2023] [Indexed: 01/15/2023] Open
Abstract
While studies on dietary nitrate (NO3-) supplementation and its impact on combat sports performance are increasing, finite conclusions from currently available investigations remain unclear. Thus, the present systematic review examined the acute and chronic ergogenic effect(s) of dietary nitrate intake from beetroot on different aspects of combat sports performance. A systematic search for randomized placebo-controlled studies investigating the effects of beetroot supplementation on combat sports outcomes was performed through Scopus, PubMed/MEDLINE, Web of Science, Scielo, Sport Discus, and Cochrane Library databases up to 2 January 2023. The different terms related to beetroot and to combat sports were connected in the search strategies using the Boolean operators 'AND' and 'OR'. A total of nine studies with good methodological quality (based on the Cochrane risk of bias tool) fulfilled the inclusion criteria. Seven studies used an acute supplementation strategy, while the other two studies utilized chronic supplementation. Findings showed beetroot intake may be an effective tool to improve oxidative metabolism and muscle force production (i.e., isokinetic and isometric) in combat sports athletes. However, these effects may depend on the population, intake duration, muscle group activated, and exercise type. Future studies are required to (1) understand the effects on female athletes and (2) elucidate the impacts of dosing protocols and specific exercise modalities for enhancing combat sports performance.
Collapse
|
8
|
Voet NBM, Saris CGJ, Thijssen DHJ, Bastiaans V, Sluijs DE, Janssen MMHP. Surface Electromyography Thresholds as a Measure for Performance Fatigability During Incremental Cycling in Patients With Neuromuscular Disorders. Front Physiol 2022; 13:821584. [PMID: 35370798 PMCID: PMC8969223 DOI: 10.3389/fphys.2022.821584] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Accepted: 02/08/2022] [Indexed: 11/13/2022] Open
Abstract
In healthy persons, there is an excellent relation between the timing of the (two) surface electromyography (sEMG) thresholds and the (two) ventilatory thresholds during exercise. The primary aim of this study was to determine the relative timing of both sEMG and ventilatory thresholds in patients with neuromuscular disorders compared with healthy subjects during a maximal ergospirometry cycling test. We hypothesized that in patients with neuromuscular disorders, the sEMG thresholds would occur relatively earlier in time than the ventilatory thresholds, compared to healthy subjects, because performance fatigability occurs more rapidly. In total, 24 healthy controls and 32 patients with a neuromuscular disorder performed a cardiopulmonary exercise test on a bicycle using a 10-min ramp protocol, during which we collected ergospirometry data: power at both ventilatory and sEMG thresholds, and sEMG data of lower leg muscles. In line with our hypothesis, normalized values for all thresholds were lower for patients than healthy subjects. These differences were significant for the first ventilatory (p = 0.008) and sEMG threshold (p < 0.001) but not for the second sEMG (p = 0.053) and ventilatory threshold (p = 0.238). Most parameters for test–retest reliability of all thresholds did not show any fixed bias, except for the second ventilatory threshold. The feasibility of the sEMG thresholds was lower than the ventilatory thresholds, particularly of the first sEMG threshold. As expected, the sEMG thresholds, particularly the first threshold, occurred relatively earlier in time than the ventilatory thresholds in patients compared with healthy subjects. A possible explanation could be (a combination of) a difference in fiber type composition, disuse, and limited muscle-specific force in patients with neuromuscular disorders. sEMG measurements during submaximal dynamic exercises are needed to generalize the measurements to daily life activities for future use in prescribing and evaluating rehabilitation interventions.
Collapse
Affiliation(s)
- Nicoline B. M. Voet
- Department of Rehabilitation, Radboud University Medical Center, Donders Institute for Brain, Cognition and Behaviour, Nijmegen, Netherlands
- Klimmendaal, Rehabilitation Center, Arnhem, Netherlands
- *Correspondence: Nicoline B. M. Voet,
| | - Christiaan G. J. Saris
- Department of Neurology, Radboud University Medical Center, Donders Institute for Brain, Cognition and Behaviour, Nijmegen, Netherlands
| | - Dick H. J. Thijssen
- Department of Physiology, Radboud University Medical Center, Donders Institute for Brain, Cognition and Behaviour, Nijmegen, Netherlands
| | - Vincent Bastiaans
- Sports Medicine Center, HAN Seneca, HAN University of Applied Sciences, Nijmegen, Netherlands
| | - David E. Sluijs
- Sports Medicine Center, HAN Seneca, HAN University of Applied Sciences, Nijmegen, Netherlands
| | - Mariska M. H. P. Janssen
- Department of Rehabilitation, Radboud University Medical Center, Donders Institute for Brain, Cognition and Behaviour, Nijmegen, Netherlands
- Klimmendaal, Rehabilitation Center, Arnhem, Netherlands
| |
Collapse
|
9
|
Kilgas MA, Yoon T, McDaniel J, Phillips KC, Elmer SJ. Physiological Responses to Acute Cycling With Blood Flow Restriction. Front Physiol 2022; 13:800155. [PMID: 35360241 PMCID: PMC8963487 DOI: 10.3389/fphys.2022.800155] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Accepted: 02/15/2022] [Indexed: 11/13/2022] Open
Abstract
Aerobic exercise with blood flow restriction (BFR) can improve muscular function and aerobic capacity. However, the extent to which cuff pressure influences acute physiological responses to aerobic exercise with BFR is not well documented. We compared blood flow, tissue oxygenation, and neuromuscular responses to acute cycling with and without BFR. Ten participants completed four intermittent cycling (6 × 2 min) conditions: low-load cycling (LL), low-load cycling with BFR at 60% of limb occlusion pressure (BFR60), low-load cycling with BFR at 80% of limb occlusion pressure (BFR80), and high-load cycling (HL). Tissue oxygenation, cardiorespiratory, metabolic, and perceptual responses were assessed during cycling and blood flow was measured during recovery periods. Pre- to post-exercise changes in knee extensor function were also assessed. BFR60 and BFR80 reduced blood flow (~33 and ~ 50%, respectively) and tissue saturation index (~5 and ~15%, respectively) when compared to LL (all p < 0.05). BFR60 resulted in lower VO2, heart rate, ventilation, and perceived exertion compared to HL (all p < 0.05), whereas BFR80 resulted in similar heart rates and exertion to HL (both p > 0.05). BFR60 and BFR80 elicited greater pain compared to LL and HL (all p < 0.05). After exercise, knee extensor torque decreased by ~18 and 40% for BFR60 and BFR80, respectively (both p < 0.05), and was compromised mostly through peripheral mechanisms. Cycling with BFR increased metabolic stress, decreased blood flow, and impaired neuromuscular function. However, only BFR60 did so without causing very severe pain (>8 on pain intensity scale). Cycling with BFR at moderate pressure may serve as a potential alternative to traditional high-intensity aerobic exercise.
Collapse
Affiliation(s)
- Matthew A Kilgas
- School of Health and Human Performance, Northern Michigan University, Marquette, MI, United States
- Department of Kinesiology and Integrative Physiology, Michigan Technological University, Houghton, MI, United States
| | - Tejin Yoon
- Department of Physical Education, Kangwon National University, Chuncheon, South Korea
| | - John McDaniel
- Department of Exercise Physiology, Kent State University, Kent, OH, United States
- Louis Stokes Cleveland Veterans Affairs Medical Center, Cleveland, OH, United States
| | - Kevin C Phillips
- Department of Kinesiology and Integrative Physiology, Michigan Technological University, Houghton, MI, United States
| | - Steven J Elmer
- Department of Kinesiology and Integrative Physiology, Michigan Technological University, Houghton, MI, United States
| |
Collapse
|
10
|
Smith CM, Salmon OF, Jenkins JR. Effect of moderate and Severe Hypoxic exposure coupled with fatigue on psychomotor vigilance testing, muscle tissue oxygenation, and muscular performance. Curr Res Physiol 2021; 4:243-251. [PMID: 34806034 PMCID: PMC8581267 DOI: 10.1016/j.crphys.2021.11.001] [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: 09/17/2021] [Revised: 11/01/2021] [Accepted: 11/02/2021] [Indexed: 01/10/2023] Open
Abstract
Purpose The purpose of this study is to examine the effects of fatigue on muscular performance, oxygenation saturation, and cognition following acute hypoxic exposure at Normoxia, Moderate Hypoxia (MH), and Severe Hypoxia (SH). Methods Twelve males performed 3 sets of leg extensions to failure under Normoxia (FiO2: 21%), MH (Fi02: 15.4%), and SH (Fi02: 12.9%). Heart rate, peripheral oxygenation saturation, total saturation index, psychomotor vigilance testing reaction time, psychomotor vigilance error rate, maximum strength, and repetitions to failure were measured throughout each visit. Results The primary findings indicated that MH and SH resulted in significant decreases in psychomotor vigilance test performance (MH: 388.25–427.17 ms, 0.41–0.33 error rate; SH: 398.17–445.42 ms reaction time, 0.25–1.00 error rate), absolute muscle tissue oxygen saturation (Abs-StO2) (MH:67.22% compared to SH:57.56%), but similar muscular strength, heart rate, and patterns of muscle tissue oxygen saturation responses (StO2%) during fatigue when compared to Normoxia. There was an acute decrease in the ability to remain vigilant and/or respond correctly to visual stimuli as indicated by the worsened reaction time (PVTRT) during MH (FiO2: 15.4%) and increased PVTRT and error rate (PVTE) during SH (FiO2: 12.9%) conditions. Conclusions Acute hypoxic exposure in the current study was not a sufficient stimuli to elicit hypoxic-related changes in HR, muscular strength (1-RM), or repetitions to failure. The SpO2 responses were hypoxic-level dependent with increasing levels of hypoxia resulting in greater and more sustained reductions in SpO2. The combined SpO2 and StO2 responses at MH and SH suggested a balance between the muscles metabolic demand remaining lower than the muscle oxygen diffusion capacity. During the SH condition, Abs-StO2 suggested greater metabolic stress than Normoxia and MH conditions during the fatiguing leg extensions. The patterns of responses for StO2% during the three sets of leg press to failure indicated that exercise is a more potent influencer to muscle oxygenation status than hypoxic conditions (FiO2: 15.4 and 12.9%). Moderate Hypoxia (FiO2: 15.4%) coupled with fatigue resulted in a decrease in reaction time. Severe Hypoxia (FiO2: 12.9%) coupled with fatigue resulted in increased error rate and a decrease in reaction time. Fatigue was the primary influencer on heart rate, muscular strength, and muscular endurance and not hypoxic exposure. Severe Hypoxia (FiO2: 12.9%) resulted in greatly reduced muscle tissue oxygenation saturation before and after fatigue.
Collapse
Affiliation(s)
- Cory M Smith
- Human & Environmental Physiology Laboratory, The University of Texas at El Paso, El Paso, TX, USA
| | - Owen F Salmon
- Human & Environmental Physiology Laboratory, The University of Texas at El Paso, El Paso, TX, USA
| | - Jasmin R Jenkins
- Interdisciplinary Health Sciences PhD Program, The University of Texas at El Paso, El Paso, TX, USA
| |
Collapse
|
11
|
Electromyographic and Systemic Physiological Thresholds in Single-Joint Elbow Flexion Movements. Int J Sports Physiol Perform 2021; 17:241-248. [PMID: 34611058 DOI: 10.1123/ijspp.2021-0163] [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: 03/26/2021] [Revised: 05/25/2021] [Accepted: 06/05/2021] [Indexed: 11/18/2022]
Abstract
PURPOSE Reported relationships between electromyographic (EMG) thresholds and systemic thresholds based on lactate, ventilation, or heart rate are contradictory. This might be related to the complexity of the investigated whole-body movements involving many muscles with different activation patterns. Therefore, the aim of the study was to investigate these relationships during an incremental single-joint exercise. METHODS Eighteen male subjects (29.7 [4.4] y) performed single-arm elbow flexions on a biceps curl machine with loads increasing every minute until exhaustion. EMG signals of the main elbow flexors (short and long head of the biceps brachii, flexor carpi radialis, and brachioradialis) as well as gas exchange variables, blood lactate concentration, and heart rate were measured, and 2 turn points based on a 3-phase model of metabolism were determined for each variable. RESULTS The first and second turn points for EMG were determined at 32.0% to 33.1% and 64.4% to 66.5% of maximal achieved performance (maximum weight), respectively. Systemic turn points were determined at 33.3% to 34.4% and 65.9% to 66.7% of maximum weight and were not significantly different from EMG turn points. Furthermore, systemic and EMG turn points showed a strong or very strong relationship at the first (ρ = .54-.93, P < .05) and second turn point (ρ = .76-.93, P < .01). CONCLUSIONS A close relationship between EMG and systemic turn points could be confirmed for the applied movement of a small muscle group. The determination of local single muscle thresholds using EMG provides additional muscle-specific information about performance-limiting properties of muscles involved in endurance-type incremental exercise.
Collapse
|
12
|
Młyńczak M, Krysztofiak H. Respiratory Activity during Exercise: A Feasibility Study on Transition Point Estimation Using Impedance Pneumography. SENSORS 2021; 21:s21186233. [PMID: 34577438 PMCID: PMC8473346 DOI: 10.3390/s21186233] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Revised: 09/09/2021] [Accepted: 09/14/2021] [Indexed: 11/24/2022]
Abstract
The current diagnostic procedures for assessing physiological response to exercise comprise blood lactates measurements, ergospirometry, and electrocardiography. The first is not continuous, the second requires specialized equipment distorting natural breathing, and the last is indirect. Therefore, we decided to perform the feasibility study with impedance pneumography as an alternative technique. We attempted to determine points in respiratory-related signals, acquired during stress test conditions, that suggest a transition similar to the gas exchange threshold. In addition, we analyzed whether or not respiratory activity reaches steady states during graded exercise. Forty-four students (35 females), practicing sports on different levels, performed a graded exercise test until exhaustion on cycloergometer. Eventually, the results from 34 of them were used. The data were acquired with Pneumonitor 2. The signals demonstrated that the steady state phenomenon is not as evident as for heart rate. The results indicated respiratory rate approaches show the transition point at the earliest (more than 6 min before the end of the exercise test on average), and the tidal volume ones at the latest (less than 5 min). A combination gave intermediate findings. The results showed the impedance pneumography appears reasonable for the transition point estimation, but this should be further studied with the reference.
Collapse
Affiliation(s)
- Marcel Młyńczak
- Institute of Metrology and Biomedical Engineering, Faculty of Mechatronics, Warsaw University of Technology, 02-525 Warsaw, Poland
- Correspondence:
| | - Hubert Krysztofiak
- Department of Applied Physiology, Mossakowski Medical Research Institute, Polish Academy of Sciences, 02-106 Warsaw, Poland;
| |
Collapse
|
13
|
Features of electromyography threshold of the respiratory muscles during incremental exercise test. Respir Physiol Neurobiol 2021; 295:103785. [PMID: 34508868 DOI: 10.1016/j.resp.2021.103785] [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: 06/22/2021] [Revised: 08/19/2021] [Accepted: 09/06/2021] [Indexed: 11/23/2022]
Abstract
In this study, we aimed to examine the electromyography threshold (EMGT) of the respiratory muscle and accessory respiratory muscles. Sixteen healthy men underwent an incremental exercise test at 15 W/minute to the end point. Expired gases and electromyograms of the respiratory and lower limb muscles were measured. The breakpoints for the EMG and expired gas data were analyzed using a segmented regression model. EMGT of the sternocleidomastoid and diaphragm was significantly more delayed than the ventilation threshold (VT) (287.94 s, 288.15 s vs. 185.5 s, p = 0.028 and 0.044, respectively). The EMGT of respiratory muscles and VT were not related, though EMGT of rectus femoris and vastus lateralis correlated with VT (r = 0.854, p < 0.001; r = 0.657, p = 0.011, respectively). EMGT of respiratory muscles may be influenced by multiple factors, such as central command and afferent input of mechanical stimulation from muscles, in addition to VT-induced changes in metabolic dynamics.
Collapse
|
14
|
Pleguezuelos E, Del Carmen A, Llorensi G, Carcole J, Casarramona P, Moreno E, Ortega P, Serra-Prat M, Palomera E, Miravitlles MM, Yebenes JC, Boixeda R, Campins L, Villelabeitia-Jaureguizar K, Garnacho-Castaño MV. Severe loss of mechanical efficiency in COVID-19 patients. J Cachexia Sarcopenia Muscle 2021; 12:1056-1063. [PMID: 34102017 PMCID: PMC8242734 DOI: 10.1002/jcsm.12739] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/24/2020] [Revised: 04/30/2021] [Accepted: 05/21/2021] [Indexed: 01/11/2023] Open
Abstract
BACKGROUND There is limited information about the impact of coronavirus disease (COVID-19) on the muscular dysfunction, despite the generalized weakness and fatigue that patients report after overcoming the acute phase of the infection. This study aimed to detect impaired muscle efficiency by evaluating delta efficiency (DE) in patients with COVID-19 compared with subjects with chronic obstructive pulmonary disease (COPD), ischaemic heart disease (IHD), and control group (CG). METHODS A total of 60 participants were assigned to four experimental groups: COVID-19, COPD, IHD, and CG (n = 15 each group). Incremental exercise tests in a cycle ergometer were performed to obtain peak oxygen uptake (VO2 peak). DE was obtained from the end of the first workload to the power output where the respiratory exchange ratio was 1. RESULTS A lower DE was detected in patients with COVID-19 and COPD compared with those in CG (P ≤ 0.033). However, no significant differences were observed among the experimental groups with diseases (P > 0.05). Lower VO2 peak, peak ventilation, peak power output, and total exercise time were observed in the groups with diseases than in the CG (P < 0.05). A higher VO2 , ventilation, and power output were detected in the CG compared with those in the groups with diseases at the first and second ventilatory threshold (P < 0.05). A higher power output was detected in the IHD group compared with those in the COVID-19 and COPD groups (P < 0.05) at the first and second ventilatory thresholds and when the respiratory exchange ratio was 1. A significant correlation (P < 0.001) was found between the VO2 peak and DE and between the peak power output and DE (P < 0.001). CONCLUSIONS Patients with COVID-19 showed marked mechanical inefficiency similar to that observed in COPD and IHD patients. Patients with COVID-19 and COPD showed a significant decrease in power output compared to IHD during pedalling despite having similar response in VO2 at each intensity. Resistance training should be considered during the early phase of rehabilitation.
Collapse
Affiliation(s)
- Eulogio Pleguezuelos
- Physical Medicine and Rehabilitation Department, Hospital de Mataró, Mataró, Spain.,Department of Experimental Science and Healthcare, Faculty of Health Sciences, Universitat Pompeu Fabra, Barcelona, Spain
| | - Amin Del Carmen
- Physical Medicine and Rehabilitation Department, Hospital de Mataró, Mataró, Spain
| | - Gemma Llorensi
- Physical Medicine and Rehabilitation Department, Hospital de Mataró, Mataró, Spain
| | - Jessica Carcole
- Physical Medicine and Rehabilitation Department, Hospital de Mataró, Mataró, Spain
| | - Paula Casarramona
- Physical Medicine and Rehabilitation Department, Hospital de Mataró, Mataró, Spain
| | - Eva Moreno
- Physical Medicine and Rehabilitation Department, Hospitalet General Hospital, L'Hospitalet de Llobregat, Spain
| | - Pilar Ortega
- Pneumology Department, Hospital de Mataró, Mataró, Spain
| | | | | | - Marc M Miravitlles
- Pneumology Department, Hospital Universitari Vall d'Hebron, Vall d'Hebron Institut de Recerca (VHIR), Vall d'Hebron Barcelona Hospital Campus, CIBER de Enfermedades Respiratorias (CIBERES), Barcelona, Spain
| | | | - Ramón Boixeda
- Department of Internal Medicine, Hospital de Mataró, CSDM, Mataró, Spain.,Grup d'Estudi al Maresme de la Pneumònia Adquirida en la Comunitat i la MPOC (GEMP@C), Mataró, Spain
| | - Lluis Campins
- Department of Pharmacy, Hospital de Mataró, CSdM, Mataró, Spain
| | | | | |
Collapse
|
15
|
García-Fernández P, Cimadevilla E, Guodemar-Pérez J, Cañuelo-Márquez AM, Heredia-Elvar JR, Fernández-Rodríguez T, Lozano-Estevan MDC, Hervás-Pérez JP, Sánchez-Calabuig MA, Garnacho-Castaño MV, Hernández Lougedo J, Maté-Muñoz JL. Muscle Recovery after a Single Bout of Functional Fitness Training. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:ijerph18126634. [PMID: 34203042 PMCID: PMC8297394 DOI: 10.3390/ijerph18126634] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/25/2021] [Revised: 06/15/2021] [Accepted: 06/17/2021] [Indexed: 01/10/2023]
Abstract
Background: Functional fitness training (FFT) is a new exercise modality that targets functional multi-joint actions via both muscle-strengthening exercises and aerobic training intervals. The aim of the study was to examine muscle recovery over a 20 min period after an FFT workout in trained adults. Materials and methods: Participants were 28 healthy trained subjects. In a single session, a countermovement jump (CMJ) was performed to determine several mechanical variables (jump height, maximum velocity, power) before (preFFT) and 4, 10, and 20 min after the FFT workout (postFFT). In parallel, capillary blood lactate concentrations were measured pre- and 3 min postFFT. Heart rate was also measured before and after the workout, and perceived exertion was measured postFFT. Results: Significant differences between the time points preFFT and 4 min and 10 min postFFT, respectively, were produced in jump height (p = 0.022, p = 0.034), maximum velocity (p = 0.016, p = 0.005), average power relative (p = 0.018, p = 0.049), and average power total (p = 0.025, p = 0.049). No differences were observed in any of the variables recorded preFFT and 20 min postFFT. Conclusions: While mechanical variables indicating muscle fatigue were reduced 4 and 10 min postFFT, pre-exercise jump ability only really started to recover 20 min after FFT although not reaching pre-exercise levels. This means that ideally intervals of around 20 min of rest should be implemented between training bouts.
Collapse
Affiliation(s)
- Pablo García-Fernández
- Department of Radiology, Rehabilitation and Physiotherapy, Complutense University of Madrid, 28040 Madrid, Spain;
| | - Eduardo Cimadevilla
- Department of Physiotherapy, Faculty of Health Sciences, Camilo José Cela University, 28692 Madrid, Spain; (E.C.); (J.G.-P.); (T.F.-R.); (J.P.H.-P.)
| | - Jesús Guodemar-Pérez
- Department of Physiotherapy, Faculty of Health Sciences, Camilo José Cela University, 28692 Madrid, Spain; (E.C.); (J.G.-P.); (T.F.-R.); (J.P.H.-P.)
| | | | - Juan Ramón Heredia-Elvar
- Department of Physical Activity and Sports Science, Alfonso X El Sabio University, 28691 Madrid, Spain; (J.R.H.-E.); (J.H.L.)
| | - Tomás Fernández-Rodríguez
- Department of Physiotherapy, Faculty of Health Sciences, Camilo José Cela University, 28692 Madrid, Spain; (E.C.); (J.G.-P.); (T.F.-R.); (J.P.H.-P.)
| | - María del Carmen Lozano-Estevan
- Department of Pharmacy, Faculty of Health Sciences, Alfonso X El Sabio University, 28691 Madrid, Spain; (M.d.C.L.-E.); (M.A.S.-C.)
| | - Juan Pablo Hervás-Pérez
- Department of Physiotherapy, Faculty of Health Sciences, Camilo José Cela University, 28692 Madrid, Spain; (E.C.); (J.G.-P.); (T.F.-R.); (J.P.H.-P.)
| | - María Aránzazu Sánchez-Calabuig
- Department of Pharmacy, Faculty of Health Sciences, Alfonso X El Sabio University, 28691 Madrid, Spain; (M.d.C.L.-E.); (M.A.S.-C.)
| | - Manuel Vicente Garnacho-Castaño
- Department of Physical Activity and Sport Sciences, TecnoCampus, College of Health Sciences, Pompeu Fabra University, 08302 Barcelona, Spain;
| | - Juan Hernández Lougedo
- Department of Physical Activity and Sports Science, Alfonso X El Sabio University, 28691 Madrid, Spain; (J.R.H.-E.); (J.H.L.)
| | - José Luis Maté-Muñoz
- Department of Physical Activity and Sports Science, Alfonso X El Sabio University, 28691 Madrid, Spain; (J.R.H.-E.); (J.H.L.)
- Correspondence:
| |
Collapse
|
16
|
Frazão M, Silva PE, Cacau LDAP, Petrucci TR, Assis MC, Santos ADC, Brasileiro-Santos MDS. EMG breakpoints for detecting anaerobic threshold and respiratory compensation point in recovered COVID-19 patients. J Electromyogr Kinesiol 2021; 59:102567. [PMID: 34174508 PMCID: PMC8186128 DOI: 10.1016/j.jelekin.2021.102567] [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: 12/28/2020] [Revised: 05/06/2021] [Accepted: 06/03/2021] [Indexed: 11/29/2022] Open
Abstract
Introduction A huge number of COVID-19 patients should be referred to rehabilitation programmes. Individualizing the exercise intensity by metabolic response provide good physiological results. The aim of this study was to investigate the validity of EMG as a non-invasive determinant of the anaerobic threshold and respiratory compensation point, for more precise exercise intensity prescription. Methods An observational cross-sectional study with 66 recovered COVID-19 patients was carried out. The patients underwent a cardiopulmonary exercise test with simultaneous assessment of muscle electromyography in vastus lateralis. EMG breakpoints were analyzed during the ramp-up protocol. The first and second EMG breakpoints were used for anaerobic threshold and respiratory compensation point determination. Results EMG and gas exchange analysis presented strong correlation in anaerobic threshold (r = 0.97, p < 0.0001) and respiratory compensation point detection (r = 0.99, p < 0.0001) detection. Bland-Altman analysis demonstrated a bias = −4.7 W (SD = 6.2 W, limits of agreement = −16.9 to 7.6) for anaerobic threshold detection in EMG compared to gas exchange analysis. In respiratory compensation point detection, Bland-Altman analysis demonstrated a bias = -2.1 W (SD = 4.5 W, limits of agreement = −10.9 to 6.6) in EMG compared to gas exchange analysis. EMG demonstrated a small effect size compared to gas exchange analysis in oxygen uptake and power output at anaerobic threshold and respiratory compensation point detection. Conclusions EMG analysis detects anaerobic threshold and respiratory compensation point without clinical significant difference than gas exchange analysis (gold standard method) in recovered COVID-19 patients.
Collapse
Affiliation(s)
- Murillo Frazão
- Laboratory of Physical Training Studies Applied to Health, Physical Education Department, Universidade Federal da Paraíba (UFPB), João Pessoa, PB, Brazil; Associate Graduate Programme in Physical Education UPE/UFPB, PB, Brazil; Lauro Wanderley University Hospital, UFPB, PB, Brazil; CLINAR - Exercise Physiology, João Pessoa, PB, Brazil.
| | - Paulo Eugênio Silva
- Clinical Physiology and Technological Innovation FICTI-CNPq, Brasília, DF, Brazil
| | | | | | - Mariela Cometki Assis
- Intervent - Infectology and Phyiotherapy, Aracaju, SE, Brazil; Unimed, Aracaju, SE, Brazil
| | - Amilton da Cruz Santos
- Laboratory of Physical Training Studies Applied to Health, Physical Education Department, Universidade Federal da Paraíba (UFPB), João Pessoa, PB, Brazil; Associate Graduate Programme in Physical Education UPE/UFPB, PB, Brazil
| | - Maria do Socorro Brasileiro-Santos
- Laboratory of Physical Training Studies Applied to Health, Physical Education Department, Universidade Federal da Paraíba (UFPB), João Pessoa, PB, Brazil; Associate Graduate Programme in Physical Education UPE/UFPB, PB, Brazil
| |
Collapse
|
17
|
Herda AA, Smith-Ryan AE, Kendall KL, Cramer JT, Stout JR. Evaluation of High-Intensity Interval Training and Beta-Alanine Supplementation on Efficiency of Electrical Activity and Electromyographic Fatigue Threshold. J Strength Cond Res 2021; 35:1535-1541. [PMID: 34027920 DOI: 10.1519/jsc.0000000000004038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
ABSTRACT Herda, AA, Smith-Ryan, AE, Kendall, KL, Cramer, JT, and Stout, JR. Evaluation of high-intensity interval training and beta-alanine supplementation on efficiency of electrical activity and electromyographic fatigue threshold. J Strength Cond Res 35(6): 1535-1541, 2021-The purpose of this study was to determine the effects of high-intensity interval training (HIIT) with or without β-alanine (BA) supplementation on the electromyographic fatigue threshold (EMGFT) and efficiency of electrical activity (EEA) in young women. Forty-four women (mean ± SD; age [yrs]: 21.7 ± 3.7; height [cm]: 166.3 ± 6.4; body mass [kg]: 66.1 ± 10.3) were randomly assigned to one of 3 treatment groups. The supplement groups performed HIIT on the cycle ergometer 3 times·wk-1 for 6 weeks. Electromyographic fatigue threshold and EEA were assessed at baseline (PRE), after 3 weeks of training (MID), and after 6 weeks of HIIT (POST). Two 2-way mixed factorial analyses of variance (time [PRE vs. MID vs. POST] × treatment (BA vs. PL vs. CON)] were used to analyze EMGFT and EEA with a predetermined level of significance α of 0.05. For EMGFT, there was no interaction (p = 0.26) and no main effect for time (p = 0.28) nor treatment (p = 0.86); thus, there were no changes in EMGFT regardless of training or supplementation status. For EEA, there was no interaction (p = 0.70) nor treatment (p = 0.79); however, there was a main effect for time (p < 0.01). Our findings indicated that neither training nor supplementation was effective in improving EMGFT in women. Efficiency of electrical activity was altered, potentially because of a learning effect. Coaches and practitioners may not use these tests to monitor training status; however, they may find EEA as a useful tool to track cycling efficiency.
Collapse
Affiliation(s)
- Ashley A Herda
- Department of Health, Sport, and Exercise Sciences, University of Kansas-Edwards Campus, Overland Park, Kansas
| | - Abbie E Smith-Ryan
- Department of Exercise and Sport Science, University of North Carolina-Chapel Hill, Chapel Hill, North Carolina
| | - Kristina L Kendall
- Department of Exercise and Sport Sciences, Edith Cowan University, Joondalup WA, Australia
| | - Joel T Cramer
- Department of Kinesiology College of Health Sciences, University of Texas-El Paso, El Paso, Texas; and
| | - Jeffrey R Stout
- Exercise Physiology & Rehabilitation Science and Kinesiology Units School of Kinesiology and Physical Therapy, University of Central Florida, Orlando, Florida
| |
Collapse
|
18
|
Viellehner J, Potthast W. The Effect of Cycling-specific Vibration on Neuromuscular Performance. Med Sci Sports Exerc 2021; 53:936-944. [PMID: 33196607 DOI: 10.1249/mss.0000000000002565] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
PURPOSE This study aimed to provide an understanding of how surface-induced vibrations in cycling interfere with short-term neuromuscular performance. METHODS The study was conducted as a cross-sectional single cohort trial. Thirty trained cyclists participated (mass = 75.9 ± 8.9 kg, body height = 1.82 ± 0.05 m, V˙O2max = 63 ± 6.8 mL·kg-1⋅min-1). The experimental intervention included a systematic variation of the two independent variables: vibration (Vib: front dropout, 44 Hz, 4.1 mm; rear dropout, 38Hz, 3.5 mm; NoVib) and cranking power (LOW, 137 ± 14 W; MED, 221 ± 18 W; HIGH, 331 ± 65 W) from individual low to submaximal intensity. Dependent variables were transmitted accelerations to the body, muscular activation (gastrocnemius medialis, gastrocnemius lateralis, soleus, vastus lateralis, vastus medialis, rectus femoris, triceps brachii, flexor carpi ulnaris, and lumbar erector spinae), heart rate, and oxygen consumption. RESULTS The main findings show that the root-mean-square of local accelerations increased with vibration at the lower extremities, the torso, and the arms-shoulder system. The activation of gastrocnemius medialis, gastrocnemius lateralis, soleus, triceps brachii, and flexor carpi ulnaris increased significantly with vibration. The activation of vastus lateralis increased significantly with vibration only at HIGH cranking power. Oxygen consumption (+2.7%) and heart rate (+5%-7%) increased significantly in the presence of vibration. CONCLUSIONS Vibration is a full-body phenomenon. However, the impact of vibration on propulsion is limited as the main propulsive muscles at the thigh are not majorly affected. The demands on the cardiopulmonary and respiratory system increased slightly in the presence of vibration.
Collapse
Affiliation(s)
- Josef Viellehner
- Institute of Biomechanics and Orthopaedics, German Sport University Cologne, Cologne, GERMANY
| | | |
Collapse
|
19
|
Pouliquen C, Nicolas G, Bideau B, Bideau N. Impact of Power Output on Muscle Activation and 3D Kinematics During an Incremental Test to Exhaustion in Professional Cyclists. Front Sports Act Living 2021; 2:516911. [PMID: 33778484 PMCID: PMC7988189 DOI: 10.3389/fspor.2020.516911] [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: 12/05/2019] [Accepted: 12/21/2020] [Indexed: 11/29/2022] Open
Abstract
This study aimed to quantify the influence of an increase in power output (PO) on joint kinematics and electromyographic (EMG) activity during an incremental test to exhaustion for a population of professional cyclists. The hip flexion/extension and internal/external rotation as well as knee abduction/adduction ranges of motion were significantly decreased at 100% of the maximal aerobic power (MAP). EMG analysis revealed a significant increase in the root mean square (RMS) for all muscles from 70% of the MAP. Gastrocnemius muscles [lateralis gastrocnemius (GasL) and medialis gastrocnemius (GasM)] were the less affected by the increase of PO. Cross-correlation method showed a significant increase in the lag angle values for VM in the last stage compared to the first stage, meaning that the onset of the activation started earlier during the pedaling cycle. Statistical Parametric Mapping (SPM) demonstrated that from 70% MAP, biceps femoris (BF), tibialis anterior (TA), gluteus maximus (GM), and rectus femoris (RF) yielded larger ranges of the crank cycle on which the level of recruitment was significantly increased. This study revealed specific muscular and kinematic coordination for professional cyclists in response to PO increase.
Collapse
Affiliation(s)
- Camille Pouliquen
- M2S Laboratory (Movement, Sports & Health), University Rennes 2, ENS Rennes, Bruz, France.,MIMETIC - Analysis-Synthesis Approach for Virtual Human Simulation, INRIA Rennes - Bretagne Atlantique, Rennes, France
| | - Guillaume Nicolas
- M2S Laboratory (Movement, Sports & Health), University Rennes 2, ENS Rennes, Bruz, France.,MIMETIC - Analysis-Synthesis Approach for Virtual Human Simulation, INRIA Rennes - Bretagne Atlantique, Rennes, France
| | - Benoit Bideau
- M2S Laboratory (Movement, Sports & Health), University Rennes 2, ENS Rennes, Bruz, France.,MIMETIC - Analysis-Synthesis Approach for Virtual Human Simulation, INRIA Rennes - Bretagne Atlantique, Rennes, France
| | - Nicolas Bideau
- M2S Laboratory (Movement, Sports & Health), University Rennes 2, ENS Rennes, Bruz, France.,MIMETIC - Analysis-Synthesis Approach for Virtual Human Simulation, INRIA Rennes - Bretagne Atlantique, Rennes, France
| |
Collapse
|
20
|
Snarr RL, Tolusso DV, Hallmark AV, Esco MR. Validity of Wearable Electromyographical Compression Shorts to Predict Lactate Threshold During Incremental Exercise in Healthy Subjects. J Strength Cond Res 2021; 35:702-708. [PMID: 29979274 DOI: 10.1519/jsc.0000000000002721] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
ABSTRACT Snarr, RL, Tolusso, DV, Hallmark, AV, and Esco, MR. Validity of wearable electromyographical compression shorts to predict lactate threshold during incremental exercise in healthy subjects. J Strength Cond Res 35(3): 702-708, 2021-Determination of lactate threshold (LT) is an important variable in improving cardiovascular endurance and performance. Unfortunately, monitoring LT during exercise uses a costly, invasive blood analysis. Recently, electromyography (EMG) has been deemed a potential method of monitoring exercise intensity and may provide a noninvasive technique to monitor lactate during exercise. The purpose of this investigation was to determine if wearable surface EMG technology, acquired from specialized compression shorts, could estimate the LT work rate during incremental cycling. Thirteen men (n = 9) and women (n = 4) completed a maximal exercise test on a cycle ergometer. Blood lactate was measured every minute, whereas EMG was recorded throughout at the site of the vastus lateralis. Lactate and EMG thresholds were calculated using the Dmax method and compared using a Wilcoxon matched-pairs signed-rank test. Results demonstrated no significant differences between lactate and EMG thresholds in regards to work output (p = 0.83), percent maximal heart rate (p = 0.13; Cohen's d = 0.43), or percent peak oxygen consumption (p = 0.64; Cohen's d = 0.09). This confirms that both lactate and EMG exhibit similar properties (i.e., increasing exponential values) during incremental exercise. A possible mechanism includes the rise in blood lactate concentration, which increases motor unit recruitment in an attempt to maintain proper cadence and force output during incremental exercise. Thus, a coincidental, exponential increase in EMG amplitude may occur. Therefore, wearable EMG compression gear may provide a viable field tool for monitoring training intensity and predicting LT work rates.
Collapse
Affiliation(s)
- Ronald L Snarr
- Department of Health Sciences and Kinesiology, Georgia Southern University, Statesboro, Georgia
| | - Danilo V Tolusso
- Department of Kinesiology, The University of Alabama, Tuscaloosa, Alabama; and
| | - Ashleigh V Hallmark
- Cardiology Imaging Clinic, The University of Alabama at Birmingham, Birmingham, Alabama
| | - Michael R Esco
- Department of Kinesiology, The University of Alabama, Tuscaloosa, Alabama; and
| |
Collapse
|
21
|
Wheelchair propulsion fatigue thresholds in electromyographic and ventilatory testing. Spinal Cord 2020; 58:1104-1111. [PMID: 32367012 DOI: 10.1038/s41393-020-0470-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2019] [Revised: 03/29/2020] [Accepted: 04/08/2020] [Indexed: 11/08/2022]
Abstract
STUDY DESIGN Qualitative study. OBJECTIVE The objective of the present study are physiological processes occurring when the intensity of manual wheelchair propulsion approaches levels causing muscular fatigue. In particular, we set out to (1) detect the electromyographic (EMG) and ventilatory fatigue threshold during a single wheelchair incremental test, (2) examine the relationship between EMG threshold (EMGT) and ventilatory threshold (VT), and (3) detect the EMG threshold differences between the propulsive and recovery muscle synergies. SETTING Biomechanics laboratory at the University of Alberta, Canada. METHODS Oxygen uptake and EMG signals from ten wheelchair users (seven males and three females) were recorded as they were each performing an incremental propulsion bout in their own wheelchairs on a wheelchair ergometer. The V-slope method was used to identify the VT, and the EMGT of each of the eight muscles (anterior deltoid, middle deltoid, posterior deltoid, infraspinatus, upper trapezius, sternal head of pectoralis major, biceps brachii, and triceps brachii) was determined using the bisegmental linear regression method. RESULTS For each participant, we were able to determine the EMGT and VT from a single incremental wheelchair propulsion bout. EMGT stands in good agreement with VT, and there was a high similarity in EMGT between push and recovery muscles (intraclass correlation coefficient = 0.91). CONCLUSION The EMG fatigue threshold method can serve as a valid and reliable tool for identifying the onset of muscular fatigue during wheelchair propulsion, thus providing a foundation for automated muscle fatigue detection/prediction in wearable technology.
Collapse
|
22
|
Hsiao CK, Tu YK, Tsai YJ, Yang CY, Lu CW. Forearm muscular strength and performance fatigability in orthopaedic surgeons when performing bone screw fixations. APPLIED ERGONOMICS 2020; 87:103135. [PMID: 32501253 DOI: 10.1016/j.apergo.2020.103135] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2019] [Revised: 04/15/2020] [Accepted: 04/21/2020] [Indexed: 06/11/2023]
Abstract
This study investigated the muscle strength and performance fatigability of the forearms in eight male orthopaedic surgeons when performing bone screw fixations. Each surgeon performed an eight-bone screws operations in a porcine femur model to simulate fractural fixation using plating technique. The pre- and post-fatigue maximum isometric forces and corresponding electromyography responses were measured to assess the forearm muscle strength loss and fatigue due to screwing. Results showed that after eight bone screws were inserted, the maximal grip force, maximal driving torque and maximal push force losses were approximately 29%, 20% and 23%, respectively. While the grip force and/or driving torque acting, both the brachioradialis and extensor carpi ulnaris had a higher percentage change of EMG than the biceps brachii. The driving forces decreased with the number of screw insertions; however, the insertion time increased parabolically with the number of screws and significantly decreased the insertion rate of the screws, indicating that forearm muscle fatigue may occur in surgeons who treat fracture fixation using more than eight bone screws.
Collapse
Affiliation(s)
- Chih-Kun Hsiao
- Department of Public Health, Kaohsiung Medical University, Kaohsiung, 807, Taiwan; Department of Orthopaedics, E-Da Hospital, Kaohsiung, 824, Taiwan
| | - Yuan-Kun Tu
- Department of Orthopaedics, E-Da Hospital, Kaohsiung, 824, Taiwan
| | - Yi-Jung Tsai
- Department of Orthopaedics, E-Da Hospital, Kaohsiung, 824, Taiwan
| | - Chun-Yuh Yang
- Department of Public Health, Kaohsiung Medical University, Kaohsiung, 807, Taiwan.
| | - Chih-Wei Lu
- Department of Industrial and Systems Engineering, Chung Yuan Christian University, Chung Li, 320, Taiwan.
| |
Collapse
|
23
|
Piucco T, Diefenthaeler F, Prosser A, Bini R. Validity of different EMG analysis methods to identify aerobic and anaerobic thresholds in speed skaters. J Electromyogr Kinesiol 2020; 52:102425. [PMID: 32413828 DOI: 10.1016/j.jelekin.2020.102425] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Revised: 04/06/2020] [Accepted: 04/29/2020] [Indexed: 11/30/2022] Open
Abstract
PURPOSE This study aimed to assess the validity of the first (EMGth1) and second (EMGth2) breakpoints in the EMG signal during skating. SCOPE Ten well-trained long track speed skaters performed a maximal incremental skating test on a slide board. EMG signals from six lower limb muscles were recorded during the last 15 s of each stage and converted to Root Mean Square for determination EMGth1 and EMGth2 using mathematical (2 and 3 linear regressions) and visual methods. CONCLUSIONS EMGth1 had a low detection rate (<50%) while EMGth2 could be identified visually in > 80% of cases, in 85% of cases using 2-lines and 63% using 3-lines regression. Quads (VL + VM) and Gluts (GM + GMd) had the highest EMGth2 detection rate for all methods (>70%). EMGth2 from Quads and Gluts detected by the 2-lines and 3-lines regression were not different than the second ventilatory threshold (VT2) (p > 0.05), while the visual method overestimated VT2 (p < 0.01). EMGth2 detected from Quads by the 2-lines regression method presented better correlation with VT2 stage (r = 0.91), lowest bias, and limit of agreement. We conclude that EMG is a valid non-invasive method to detect VT2 during skating when using a mathematical method to determine EMGth2.
Collapse
Affiliation(s)
- Tatiane Piucco
- Health and Physical Education Department, Mount Royal University, Mount Royal Gate SW, Calgary, AB T3E 6K6, Canada.
| | - Fernando Diefenthaeler
- Center of Sports, Federal University of Santa Catarina, UFSC Campus Trindade, Av. César Seara, Florianópolis, SC 88040-900, Brazil
| | - Anthony Prosser
- Health and Physical Education Department, Mount Royal University, Mount Royal Gate SW, Calgary, AB T3E 6K6, Canada
| | - Rodrigo Bini
- Rural Health School, Flora Hill Campus, La Trobe University, Bendigo 3550, Victoria, Australia
| |
Collapse
|
24
|
Ieno C, Baldassarre R, Quagliarotti C, Bonifazi M, Piacentini MF. Session RPE Breakpoints Corresponding to Intensity Thresholds in Elite Open Water Swimmers. J Funct Morphol Kinesiol 2020; 5:jfmk5010021. [PMID: 33467237 PMCID: PMC7739345 DOI: 10.3390/jfmk5010021] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Revised: 03/10/2020] [Accepted: 03/13/2020] [Indexed: 11/22/2022] Open
Abstract
This study aims to assess the correspondence between session rating of perceived exertion (sRPE) breakpoints with both the first lactate threshold (LT1) and the second lactate threshold (LT2) in elite open water swimmers (OWS). Six elite OWS of the National Olympic Team specialized in distances between 5 and 25 km participated to the study. OWS performed a set of 6 times 500 m incremental swimming step test during which blood lactate concentration (BLC), split time (ST), stroke frequency (SF), and rating of perceived exertion (RPE) were collected. To assess the corresponding breakpoints, we considered LT1 as the highest workload not associated with rise in BLC and LT2 as the increase of 2mM above LT1. According to the LT1 and LT2, the identified zones were: Z1 ≤3, Z2 between 4 and 6, Z3 ≥ 7. In conclusion, the intensity zones determined for OWS resulted different from what previously reported for other endurance disciplines.
Collapse
Affiliation(s)
- Cristian Ieno
- University of Rome Foro Italico, 00135 Rome, Italy; (C.I.); (R.B.); (C.Q.)
| | - Roberto Baldassarre
- University of Rome Foro Italico, 00135 Rome, Italy; (C.I.); (R.B.); (C.Q.)
- Italian Swimming Federation 2, 00135 Rome, Italy;
| | | | - Marco Bonifazi
- Italian Swimming Federation 2, 00135 Rome, Italy;
- Department of Medical, Surgical and Neuro Sciences, University of Siena, 53100 Siena, Italy
| | | |
Collapse
|
25
|
Isometric-based EMG threshold in girls and women. Eur J Appl Physiol 2020; 120:907-914. [PMID: 32124008 DOI: 10.1007/s00421-020-04331-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Accepted: 02/17/2020] [Indexed: 10/24/2022]
Abstract
BACKGROUND The electromyographic threshold (EMGTh) has been suggested to indicate the onset of accelerated higher-threshold (type-II) MU recruitment. Previous research has demonstrated that boys' EMGTh occurs at higher relative exercise intensities than men's in both cycling- and isometric-based testing. Girls‒women EMGTh differences were demonstrated only in cycling, but findings were clouded by low EMGTh-detection rates in women (68%) and particularly in girls (45%) PURPOSE: To examine the EMGTh, in girls and women, using the same males-employed isometric-based test protocol, and compare the females' findings with those previously obtained in the males. METHODS Seventeen girls and 17 women had their EMGTh determined as well as their one-repetition-maximum isometric knee-extension strength (1RM). Vastus-lateralis sEMG root mean square was recorded and the EMGTh was defined as the exercise intensity (%1RM) at the bi-segmental point of the least sum of squares. RESULTS EMGTh was detected in 88.2% of girls and 94.1% of women and occurred at higher relative intensities in the girls than in women (56.0 ± 11.1 vs. 47.7 ± 8.0% 1RM). The girls' 1RM (normalized to lean body mass) was only 69.1% that of the women. CONCLUSIONS Girls' EMGTh values are higher compared with women's, possibly reflecting lower ability to activate higher-threshold (type-II) motor units. The females' EMGTh and detection-rate values were similar to the corresponding values previously observed in males. The females' age-related difference in the recruitment of higher-threshold motor units, as reflected by the EMGTh, appears to be on par with the males.
Collapse
|
26
|
Kouwijzer I, Valize M, Valent LJM, Grandjean Perrenod Comtesse P, van der Woude LHV, de Groot S. The influence of protocol design on the identification of ventilatory thresholds and the attainment of peak physiological responses during synchronous arm crank ergometry in able-bodied participants. Eur J Appl Physiol 2019; 119:2275-2286. [PMID: 31435767 PMCID: PMC6763408 DOI: 10.1007/s00421-019-04211-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Accepted: 08/13/2019] [Indexed: 11/26/2022]
Abstract
Purpose To examine the effects of stage duration on power output (PO), oxygen uptake (VO2), and heart rate (HR) at peak level and ventilatory thresholds during synchronous arm crank ergometry. Methods Nineteen healthy participants completed a ramp, 1-min stepwise, and 3-min stepwise graded arm crank exercise test. PO, VO2, and HR at the first and second ventilatory threshold (VT1, VT2) and peak level were compared among the protocols: a repeated measures analysis of variance was performed to test for systematic differences, while intraclass correlation coefficients (ICC) and Bland–Altman plots were calculated to determine relative and absolute agreement. Results Systematic differences among the protocols were found for PO at VT1, VT2, and peak level. At peak level, PO differed significantly among all protocols (ramp: 115 ± 37 W; 1-min stepwise: 108 ± 34 W; 3-min stepwise: 94 ± 31 W, p ≤ 0.01). No systematic differences for HR or VO2 were found among the protocols. VT1 and VT2 were identified at 52% and 74% of VO2peak, respectively. The relative agreement among protocols varied (ICC 0.02–0.97), while absolute agreement was low with small-to-large systematic error and large random error. Conclusions PO at VTs and peak level was significantly higher in short-stage protocols compared with the 3-min stepwise protocol, whereas HR and VO2 showed no differences. Therefore, training zones based on PO determined in short-stage protocols might give an overestimation. Moreover, due to large random error in HR at VTs between the protocols, it is recommended that different protocols should not be used interchangeably within individuals.
Collapse
Affiliation(s)
- Ingrid Kouwijzer
- Research and Development, Heliomare Rehabilitation Center, Wijk aan Zee, The Netherlands. .,Center for Human Movement Sciences, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands. .,Amsterdam Rehabilitation Research Center
- Reade, Amsterdam, The Netherlands.
| | - Mitch Valize
- Amsterdam Rehabilitation Research Center
- Reade, Amsterdam, The Netherlands.,Faculty of Health Medicine and Life Sciences, Maastricht University, Maastricht, The Netherlands
| | - Linda J M Valent
- Research and Development, Heliomare Rehabilitation Center, Wijk aan Zee, The Netherlands
| | | | - Lucas H V van der Woude
- Center for Human Movement Sciences, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.,Center for Rehabilitation, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Sonja de Groot
- Center for Human Movement Sciences, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.,Amsterdam Rehabilitation Research Center
- Reade, Amsterdam, The Netherlands
| |
Collapse
|
27
|
Pallarés JG, Cerezuela-Espejo V, Morán-Navarro R, Martínez-Cava A, Conesa E, Courel-Ibáñez J. A New Short Track Test to Estimate the V[Combining Dot Above]O2max and Maximal Aerobic Speed in Well-Trained Runners. J Strength Cond Res 2019; 33:1216-1221. [PMID: 31033773 DOI: 10.1519/jsc.0000000000003121] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Pallarés, JG, Cerezuela-Espejo, V, Morán-Navarro, R, Martínez-Cava, A, Conesa, E, and Courel-Ibáñez, J. A new short track test to estimate the V[Combining Dot Above]O2max and maximal aerobic speed in well-trained runners. J Strength Cond Res 33(5): 1216-1221, 2019-This study was designed to validate a new short track test (Track(1:1)) to estimate running performance parameters maximal oxygen uptake (V[Combining Dot Above]O2max) and maximal aerobic speed (MAS), based on a laboratory treadmill protocol and gas exchange data analysis (Lab(1:1)). In addition, we compared the results with the University of Montreal Track Test (UMTT). Twenty-two well-trained male athletes (V[Combining Dot Above]O2max 60.3 ± 5.9 ml·kg·min; MAS ranged from 17.0 to 20.3 km·h) performed 4 testing protocols: 2 in laboratory (Lab(1:1)-pre and Lab(1:1)) and 2 in the field (UMTT and Track(1:1)). The Lab(1:1)-pre was designed to determine individuals' Vpeak and set initial speeds for the subsequent Lab(1:1) short ramp graded exercise testing protocol, starting at 13 km·h less than each athlete's Vpeak, with 1 km·h increments per minute until exhaustion. The Track(1:1) was a reproduction of the Lab(1:1) protocol in the field. A novel equation was yielded to estimate the V[Combining Dot Above]O2max from the Vpeak achieved in the Track(1:1). Results revealed that the UMTT significantly underestimated the Vpeak (-4.2%; bias = -0.8 km·h; p < 0.05), which notably altered the estimations (MAS: -2.6%, bias = -0.5 km·h; V[Combining Dot Above]O2max: 4.7%, bias = 2.9 ml·kg·min). In turn, data from Track(1:1) were very similar to the laboratory test and gas exchange methods (Vpeak: -0.6%, bias = <0.1 km·h; MAS: 0.3%, bias = <0.1 km·h; V[Combining Dot Above]O2max: 0.4%, bias = 0.2 ml·kg·min, p > 0.05). Thus, the current Track(1:1) test emerges as a better alternative than the UMTT to estimate maximal running performance parameters in well-trained and highly trained athletes on the field.
Collapse
Affiliation(s)
- Jesús G Pallarés
- Human Performance and Sports Science Laboratory, Faculty of Sport Sciences, University of Murcia, Spain
| | | | | | | | | | | |
Collapse
|
28
|
Isometric-based test improves EMG-threshold determination in boys vs. men. Eur J Appl Physiol 2019; 119:1971-1979. [PMID: 31273453 DOI: 10.1007/s00421-019-04185-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2019] [Accepted: 06/28/2019] [Indexed: 10/26/2022]
Abstract
BACKGROUND Children have been hypothesized to utilize higher-threshold (type-II) motor units (MUs) to a lesser extent than adults. Two recent studies, using a cycling-based EMG-threshold (EMGTh) protocol, supported the hypothesis, showing children's EMGTh intensities to be higher than adults'. Conclusions, however, were hampered by children's low EMGTh detection rates. Insufficiently high contractile forces at exhaustion were postulated as the reason for non-detection, predominantly in children. An intermittent isometric contraction test (IICT) protocol facilitates higher contractile forces prior to exhaustion and was shown effective in EMGTh testing of adults. PURPOSE Determine whether an IICT protocol would enhance EMGTh detection in children, and consequently increase the magnitude of the previously observed child-adult EMGTh differences. METHODS 18 boys and 21 men completed one-repetition-maximum (1RM) isometric knee-extension test. The IICT protocol followed, commencing at 25%1RM and comprising five isometric contractions per load, incremented by ~ 3%1RM to exhaustion. Vastus lateralis surface EMG was recorded and EMGTh, expressed as %1RM, was defined as the onset of the EMG-response's steeper segment. RESULTS EMGTh was detected in 88.9% of boys and 95.2% of men, and occurred at higher relative intensities in boys (56.4 ± 9.2%1RM) than in men (46.0 ± 6.8%1RM). This 10.4% difference was 57% greater than the corresponding, previously reported cycling-based age-related difference. CONCLUSIONS With the boys' detection rate nearly on par with the men's, the IICT protocol appears to overcome much of the intensity limitation of cycling-based protocols and provide a more sensitive EMGTh detection tool, thus extending the previously observed boys‒men difference. This difference adds supports to the notion of children's more limited type-II MU recruitment capacity.
Collapse
|
29
|
Carbohydrate Availability and Physical Performance: Physiological Overview and Practical Recommendations. Nutrients 2019; 11:nu11051084. [PMID: 31100798 PMCID: PMC6566225 DOI: 10.3390/nu11051084] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2019] [Revised: 05/11/2019] [Accepted: 05/13/2019] [Indexed: 12/18/2022] Open
Abstract
Strong evidence during the last few decades has highlighted the importance of nutrition for sport performance, the role of carbohydrates (CHO) being of special interest. Glycogen is currently not only considered an energy substrate but also a regulator of the signaling pathways that regulate exercise-induced adaptations. Thus, low or high CHO availabilities can result in both beneficial or negative results depending on the purpose. On the one hand, the depletion of glycogen levels is a limiting factor of performance during sessions in which high exercise intensities are required; therefore ensuring a high CHO availability before and during exercise is of major importance. A high CHO availability has also been positively related to the exercise-induced adaptations to resistance training. By contrast, a low CHO availability seems to promote endurance-exercise-induced adaptations such as mitochondrial biogenesis and enhanced lipolysis. In the present narrative review, we aim to provide a holistic overview of how CHO availability impacts physical performance as well as to provide practical recommendations on how training and nutrition might be combined to maximize performance. Attending to the existing evidence, no universal recommendations regarding CHO intake can be given to athletes as nutrition should be periodized according to training loads and objectives.
Collapse
|
30
|
Pawlak-Chaouch M, Boissière J, Munyaneza D, Gamelin FX, Cuvelier G, Berthoin S, Aucouturier J. Beetroot Juice Does Not Enhance Supramaximal Intermittent Exercise Performance in Elite Endurance Athletes. J Am Coll Nutr 2019; 38:729-738. [DOI: 10.1080/07315724.2019.1601601] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
- Mehdi Pawlak-Chaouch
- Sport, Health and Society, URePSSS–Pluridisciplinary Research Unit, Lille University, Lille, France
| | - Julien Boissière
- Sport, Health and Society, URePSSS–Pluridisciplinary Research Unit, Lille University, Lille, France
| | - Désiré Munyaneza
- Sport, Health and Society, URePSSS–Pluridisciplinary Research Unit, Lille University, Lille, France
| | - François-Xavier Gamelin
- Sport, Health and Society, URePSSS–Pluridisciplinary Research Unit, Lille University, Lille, France
| | - Grégory Cuvelier
- Laboratory of Exercise and Movement, Provincial School of Hainaut (HEPH)-Condorcet, Tournai, Belgium
| | - Serge Berthoin
- Sport, Health and Society, URePSSS–Pluridisciplinary Research Unit, Lille University, Lille, France
| | - Julien Aucouturier
- Sport, Health and Society, URePSSS–Pluridisciplinary Research Unit, Lille University, Lille, France
| |
Collapse
|
31
|
Noble EB, Pilarski JM, Vora HK, Zuniga JM, Malek MH. Log-Transformed Electromyography Amplitude-Power Output Relationship: Single-Leg Knee-Extensor Versus Single-Leg Cycle Ergometry. J Strength Cond Res 2019; 33:1311-1319. [PMID: 31033774 DOI: 10.1519/jsc.0000000000001950] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Noble, EB, Pilarski, JM, Vora, HK, Zuniga, JM, and Malek, MH. Log-transformed electromyography amplitude-power output relationship: single-leg knee-extensor versus single-leg cycle ergometry. J Strength Cond Res 33(5): 1311-1319, 2019-Comparing and contrasting motor unit recruitment and activation for the same muscles for multiple versus single-joint exercise may provide a better understanding of neuromuscular fatigue. The purpose of this study, therefore, is to compare the slope and y-intercept terms for the 3 superficial quadriceps femoris (QF) (vastus lateralis, rectus femoris, and vastus medialis) muscles derived from the log-transformed electromyography (EMG) amplitude-power output relationship between the single-leg knee-extensor ergometry (KE) and the single-leg cycle ergometry (CE). Ten healthy college-aged men who engaged in regular physical activity visited the laboratory on 2 occasions separated by 7 days to perform either single-leg CE or single-leg KE in a randomized order. For each visit, subjects performed incremental exercise until voluntary fatigue. Electromyography electrodes were placed on the superficial QF muscles. The slope and y-intercept terms, for each muscle, for the EMG amplitude versus power output relationship was examined using the log-transformed model for each subject's data. The results indicated no significant (p > 0.05) mean differences for either slope or y-intercept terms between exercise modes and across muscles. In addition, separate repeated-measures analyses of variance (ANOVAs) were used to determine mean differences for the slope and y-intercept values between the 3 muscles. In addition, separate 2 (mode: CE or KE) × intensity (intensity: 30, 60, and 90% of maximal workload) repeated-measures ANOVAs were conducted for each muscle. There was a significant (p < 0.05) mode × exercise intensity interaction for each muscle. Follow-up testing indicated that in most cases, the normalized EMG amplitude was significantly higher for single-leg KE than single-leg CE. These results indicated that incremental single-leg KE activates the superficial QF muscles significantly greater than single-leg CE.
Collapse
Affiliation(s)
- Eric B Noble
- Physical Therapy Program, Department of Health Care Sciences, Wayne State University, College of Pharmacy and Health Sciences, Detroit, Michigan.,Integrative Physiology of Exercise Laboratory, Department of Health Care Sciences, Wayne State University, College of Pharmacy and Health Sciences, Detroit, Michigan
| | - Joshua M Pilarski
- Physical Therapy Program, Department of Health Care Sciences, Wayne State University, College of Pharmacy and Health Sciences, Detroit, Michigan.,Integrative Physiology of Exercise Laboratory, Department of Health Care Sciences, Wayne State University, College of Pharmacy and Health Sciences, Detroit, Michigan
| | - Harshal K Vora
- Physical Therapy Program, Department of Health Care Sciences, Wayne State University, College of Pharmacy and Health Sciences, Detroit, Michigan.,Integrative Physiology of Exercise Laboratory, Department of Health Care Sciences, Wayne State University, College of Pharmacy and Health Sciences, Detroit, Michigan
| | - Jorge M Zuniga
- Department of Biomechanics, University of Nebraska, Omaha, College of Education, Omaha, Nebraska
| | - Moh H Malek
- Physical Therapy Program, Department of Health Care Sciences, Wayne State University, College of Pharmacy and Health Sciences, Detroit, Michigan.,Integrative Physiology of Exercise Laboratory, Department of Health Care Sciences, Wayne State University, College of Pharmacy and Health Sciences, Detroit, Michigan
| |
Collapse
|
32
|
Evaluation of the Electromyography Test for the Analysis of the Aerobic-Anaerobic Transition in Elite Cyclists during Incremental Exercise. APPLIED SCIENCES-BASEL 2019. [DOI: 10.3390/app9030589] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
(1) Background: The aim of this study was to investigate the validity and reliability of surface electromyography (EMG) for automatic detection of the aerobic and anaerobic thresholds during an incremental continuous cycling test using 1 min exercise periods in elite cyclists. (2) Methods: Sixteen well-trained cyclists completed an incremental exercise test (25 W/1 min) to exhaustion. Surface bipolar EMG signals were recorded from the vastus lateralis, vastus medialis, biceps femoris, and gluteus maximus, and the root mean square (RMS) were assessed. The multi-segment linear regression method was used to calculate the first and second EMG thresholds (EMGT1 and EMGT2). During the test, gas exchange data were collected to determine the first and second ventilatory thresholds (VT1 and VT2). (3) Results: Two breakpoints (thresholds) were identified in the RMS EMG vs. time curve for all muscles in 75% of participants. The two breakpoints, EMGT1 and EMGT2, were detected at around 70%–80% and 90%–95% of VO2MAX, respectively. No significant differences were found between the means of VT1 and EMGT1 for the vastii and biceps femoris muscles (p > 0.05). There were no significant differences between means of EMGT2 and VT2 (p > 0.05). (4) Conclusions: It is concluded that the multi-segment linear regression algorithm is a valid non-invasive method for analyzing the aerobic-anaerobic transition during incremental tests with 1 min stage durations.
Collapse
|
33
|
Onset of Accelerated Muscle Deoxygenation During the 20-m Shuttle Run Test in Boys. Pediatr Exerc Sci 2018; 30:474-479. [PMID: 30004296 DOI: 10.1123/pes.2017-0210] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
PURPOSE This study aimed to compare the relative exercise intensity at which the onset of accelerated muscle deoxygenation occurs during the 20-m shuttle run test (20mSRT) between boys and men and to examine whether the timing of the onset of acceleration appearance is related to 20mSRT performance in boys. METHODS Twenty-four boys performed the 20mSRT, during which concentration changes in oxygenated and deoxygenated hemoglobin and myoglobin (ΔOxy-Hb and ΔDeoxy-Hb, respectively) in the m. vastus lateralis were monitored using a portable near-infrared spectroscopy device. The boys' data were compared with those of 29 men in a previous study. RESULTS An onset of accelerated decrease in Δ[Oxy-Hb - Deoxy-Hb] was found in 11 of the 24 boys (45.8%) and 20 of the 29 men (69.0%) and was found at a higher relative exercise intensity in the boys than in the men. The number of laps at which the onset of acceleration occurred correlated with total laps in the boys (r = .87). CONCLUSIONS These findings demonstrate that the onset of accelerated muscle deoxygenation during the 20mSRT occurs at a higher relative exercise intensity in boys than in men. Our findings also show that the timing of the onset of acceleration appearance is associated with 20mSRT performance in boys.
Collapse
|
34
|
Finkel A, Röhrich MA, Maassen N, Lützow M, Blau LS, Hanff E, Tsikas D, Maassen M. Long-term effects of NO3- on the relationship between oxygen uptake and power after three weeks of supplemented HIHVT. J Appl Physiol (1985) 2018; 125:1997-2007. [PMID: 30359537 DOI: 10.1152/japplphysiol.00176.2018] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
The aim of this study was to investigate the later effects of daily NO3- supplementation over 3 wk of training on the relationship between O2 uptake and power at different intensities with an incremental test (IT), a double-wingate test (WT), and an endurance capacity test at 80% Wmax (ECT) before and after the supplementation period. Seventeen male recreational athletes participated in this double-blind placebo (PL)-controlled study. Subjects participated in a 3-wk intermittent high-intensity, high-volume training period with 45 intervals of Wmax - 10 W and an active recovery period of 10 W in between with dietary NO3- (NaNO3) or placebo supplementation (NaCl) (both 8.5 mg·kg-1·day-1) on a cycle ergometer. During a training session, plasma [ NO3- ] ( P < 0.001) and plasma [ NO2- ] ( P < 0.01) were higher in nitrate (N), whereas in pre- and posttests mean plasma [ NO3- ] and [ NO2- ] were not different between groups. In the WT [48 h after cessation of supplementation (C)], the ratio between V̇o2 and power decreased in N ( P < 0.01) with no changes in PL. Endurance capacity (4-5 days after C) similarly increased in both groups ( P < 0.01). However, the total oxygen consumption decreased by 5% ( P < 0.01) in N, with no change in PL. The slope of V̇o2·W-1 in IT (5-7 days after C) decreased in N ( P < 0.01), whereas no changes were found in PL. During low- and moderate-intensity workloads, no changes and differences in V̇o2 could be detected. We conclude that nitrate supplementation causes a sustaining reduction of the oxygen cost per watt during exercise with a large recruitment of type II muscle fibers without affecting endurance capacity. NEW & NOTEWORTHY Because most studies focused on the acute effects of NO3- supplementation on exercise performance during a supplementation period, the sustainability of the effects of the NO3- supplementation remain unknown. We followed the development of V̇o2/W at different intensities during the first week after cessation of daily NO3- supplementation over 3 wk. The results indicate that NO3- supplementation has a long-term effect for at least 7 days after cessation during heavy all-out workloads without affecting endurance capacity.
Collapse
Affiliation(s)
- Armin Finkel
- Institute of Sport Medicine, Hannover Medical School , Hannover , Germany.,Institute of Sports Science, Leibniz University Hannover , Hannover , Germany
| | | | - Norbert Maassen
- Institute of Sport Medicine, Hannover Medical School , Hannover , Germany.,Institute of Sports Science, Leibniz University Hannover , Hannover , Germany
| | - Moritz Lützow
- Institute of Sport Medicine, Hannover Medical School , Hannover , Germany
| | - Larissa Sarah Blau
- Institute of Sport Medicine, Hannover Medical School , Hannover , Germany
| | - Erik Hanff
- Institute of Toxicology, Core-Unit, Proteomics, Hannover Medical School , Hannover , Germany
| | - Dimitrios Tsikas
- Institute of Toxicology, Core-Unit, Proteomics, Hannover Medical School , Hannover , Germany
| | - Mirja Maassen
- Institute of Sport Medicine, Hannover Medical School , Hannover , Germany.,Institute of Sports Science, Leibniz University Hannover , Hannover , Germany
| |
Collapse
|
35
|
Cerezuela-Espejo V, Courel-Ibáñez J, Morán-Navarro R, Martínez-Cava A, Pallarés JG. The Relationship Between Lactate and Ventilatory Thresholds in Runners: Validity and Reliability of Exercise Test Performance Parameters. Front Physiol 2018; 9:1320. [PMID: 30319439 PMCID: PMC6167480 DOI: 10.3389/fphys.2018.01320] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2018] [Accepted: 08/31/2018] [Indexed: 01/09/2023] Open
Abstract
The aims of this study were (1) to establish the best fit between ventilatory and lactate exercise performance parameters in running and (2) to explore novel alternatives to estimate the maximal aerobic speed (MAS) in well-trained runners. Twenty-two trained male athletes ( V ˙ O2max 60.2 ± 4.3 ml·kg·min-1) completed three maximal graded exercise tests (GXT): (1) a preliminary GXT to determine individuals' MAS; (2) two experimental GXT individually adjusted by MAS to record the speed associated to the main aerobic-anaerobic transition events measured by indirect calorimetry and capillary blood lactate (CBL). Athletes also performed several 30 min constant running tests to determine the maximal lactate steady state (MLSS). Reliability analysis revealed low CV (<3.1%), low bias (<0.5 km·h-1), and high correlation (ICC > 0.91) for all determinations except V-Slope (ICC = 0.84). Validity analysis showed that LT, LT+1.0, and LT+3.0 mMol·L-1 were solid predictors of VT1 (-0.3 km·h-1; bias = 1.2; ICC = 0.90; p = 0.57), MLSS (-0.2 km·h-1; bias = 1.2; ICC = 0.84; p = 0.74), and VT2 (<0.1 km·h-1; bias = 1.3; ICC = 0.82; p = 0.9l9), respectively. MLSS was identified as a different physiological event and a midpoint between VT1 (bias = -2.0 km·h-1) and VT2 (bias = 2.3 km·h-1). MAS was accurately estimated (SEM ± 0.3 km·h-1) from peak velocity (Vpeak) attained during GXT with the equation: MASEST (km·h-1) = Vpeak (km·h-1) * 0.8348 + 2.308. Current individualized GXT protocol based on individuals' MAS was solid to determine both maximal and submaximal physiological parameters. Lactate threshold tests can be a valid and reliable alternative to VT and MLSS to identify the workloads at the transition from aerobic to anaerobic metabolism in well-trained runners. In contrast with traditional assumption, the MLSS constituted a midpoint physiological event between VT1 and VT2 in runners. The Vpeak stands out as a powerful predictor of MAS.
Collapse
Affiliation(s)
- Víctor Cerezuela-Espejo
- Human Performance and Sports Science Laboratory, Faculty of Sport Sciences, University of Murcia, Murcia, Spain
| | - Javier Courel-Ibáñez
- Human Performance and Sports Science Laboratory, Faculty of Sport Sciences, University of Murcia, Murcia, Spain
| | - Ricardo Morán-Navarro
- Human Performance and Sports Science Laboratory, Faculty of Sport Sciences, University of Murcia, Murcia, Spain
| | - Alejandro Martínez-Cava
- Human Performance and Sports Science Laboratory, Faculty of Sport Sciences, University of Murcia, Murcia, Spain
| | - Jesús G Pallarés
- Human Performance and Sports Science Laboratory, Faculty of Sport Sciences, University of Murcia, Murcia, Spain
| |
Collapse
|
36
|
Sekiguchi H, Tamaki Y, Kondo Y, Nakamura H, Hanashiro K, Yonemoto K, Moritani T, Kukita I. Surface electromyographic evaluation of the neuromuscular activation of the inspiratory muscles during progressively increased inspiratory flow under inspiratory-resistive loading. Physiol Int 2018; 105:86-99. [PMID: 29602291 DOI: 10.1556/2060.105.2018.1.3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
This study aimed to evaluate neuromuscular activation in the scalene and sternocleidomastoid muscles using surface electromyography (EMG) during progressively increased inspiratory flow, produced by increasing the respiratory rate under inspiratory-resistive loading using a mask ventilator. Moreover, we attempted to identify the EMG inflection point (EMGIP) on the graph, at which the root mean square (RMS) of the EMG signal values of the inspiratory muscles against the inspiratory flow velocity acceleration abruptly increases, similarly to the EMG anaerobic threshold (EMGAT) reported during incremental-resistive loading in other skeletal muscles. We measured neuromuscular activation of healthy male subjects and found that the inspiratory flow velocity increased by approximately 1.6-fold. We successfully observed an increase in RMS that corresponded to inspiratory flow acceleration with ρ ≥ 0.7 (Spearman's rank correlation) in 17 of 27 subjects who completed the experimental protocol. To identify EMGIP, we analyzed the fitting to either a straight or non-straight line related to the increasing inspiratory flow and RMS using piecewise linear spline functions. As a result, EMGIP was identified in the scalene and sternocleidomastoid muscles of 17 subjects. We believe that the identification of EMGIP in this study infers the existence of EMGAT in inspiratory muscles. Application of surface EMG, followed by identification of EMGIP, for evaluating the neuromuscular activation of respiratory muscles may be allowed to estimate the signs of the respiratory failure, including labored respiration, objectively and non-invasively accompanied using accessory muscles in clinical respiratory care.
Collapse
Affiliation(s)
- H Sekiguchi
- 1 Department of Intensive Care, Tomishiro Central Hospital , Okinawa, Japan.,2 Department of Emergency and Critical Care Medicine, Graduate School of Medicine, University of the Ryukyus , Okinawa, Japan
| | - Y Tamaki
- 2 Department of Emergency and Critical Care Medicine, Graduate School of Medicine, University of the Ryukyus , Okinawa, Japan
| | - Y Kondo
- 2 Department of Emergency and Critical Care Medicine, Graduate School of Medicine, University of the Ryukyus , Okinawa, Japan
| | - H Nakamura
- 3 Faculty of Biomedical Engineering, Department of Health-Promotion and Sports Science, Osaka Electro-Communication University , Osaka, Japan
| | - K Hanashiro
- 4 Department of Public Health and Hygiene, Graduate School of Medicine, University of the Ryukyus , Okinawa, Japan
| | - K Yonemoto
- 5 Faculty of Medicine, Advanced Medical Research Center, University of the Ryukyus , Okinawa, Japan
| | - T Moritani
- 6 Department of Applied Physiology, Institute for the Promotion of Common Education, Kyoto Sangyo University , Kyoto, Japan
| | - I Kukita
- 2 Department of Emergency and Critical Care Medicine, Graduate School of Medicine, University of the Ryukyus , Okinawa, Japan
| |
Collapse
|
37
|
EMG amplitude, fatigue threshold, and time to task failure: A meta-analysis. J Sci Med Sport 2018; 21:736-741. [DOI: 10.1016/j.jsams.2017.11.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2017] [Revised: 10/02/2017] [Accepted: 11/05/2017] [Indexed: 11/23/2022]
|
38
|
Belbasis A, Fuss FK. Muscle Performance Investigated With a Novel Smart Compression Garment Based on Pressure Sensor Force Myography and Its Validation Against EMG. Front Physiol 2018; 9:408. [PMID: 29725306 PMCID: PMC5917022 DOI: 10.3389/fphys.2018.00408] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2017] [Accepted: 04/04/2018] [Indexed: 11/21/2022] Open
Abstract
Muscle activity and fatigue performance parameters were obtained and compared between both a smart compression garment and the gold-standard, a surface electromyography (EMG) system during high-speed cycling in seven participants. The smart compression garment, based on force myography (FMG), comprised of integrated pressure sensors that were sandwiched between skin and garment, located on five thigh muscles. The muscle activity was assessed by means of crank cycle diagrams (polar plots) that displayed the muscle activity relative to the crank cycle. The fatigue was assessed by means of the median frequency of the power spectrum of the EMG signal; the fractal dimension (FD) of the EMG signal; and the FD of the pressure signal. The smart compression garment returned performance parameters (muscle activity and fatigue) comparable to the surface EMG. The major differences were that the EMG measured the electrical activity, whereas the pressure sensor measured the mechanical activity. As such, there was a phase shift between electrical and mechanical signals, with the electrical signals preceding the mechanical counterparts in most cases. This is specifically pronounced in high-speed cycling. The fatigue trend over the duration of the cycling exercise was clearly reflected in the fatigue parameters (FDs and median frequency) obtained from pressure and EMG signals. The fatigue parameter of the pressure signal (FD) showed a higher time dependency (R2 = 0.84) compared to the EMG signal. This reflects that the pressure signal puts more emphasis on the fatigue as a function of time rather than on the origin of fatigue (e.g., peripheral or central fatigue). In light of the high-speed activity results, caution should be exerted when using data obtained from EMG for biomechanical models. In contrast to EMG data, activity data obtained from FMG are considered more appropriate and accurate as an input for biomechanical modeling as they truly reflect the mechanical muscle activity. In summary, the smart compression garment based on FMG is a valid alternative to EMG-garments and provides more accurate results at high-speed activity (avoiding the electro-mechanical delay), as well as clearly measures the progress of muscle fatigue over time.
Collapse
Affiliation(s)
- Aaron Belbasis
- School of Engineering, RMIT University, Melbourne, VIC, Australia
| | - Franz Konstantin Fuss
- Smart Equipment Engineering and Wearable Technology Program, Centre for Design Innovation, Swinburne University of Technology, Melbourne, VIC, Australia
| |
Collapse
|
39
|
Hering GO, Hennig EM, Riehle HJ, Stepan J. A Lactate Kinetics Method for Assessing the Maximal Lactate Steady State Workload. Front Physiol 2018; 9:310. [PMID: 29651253 PMCID: PMC5884876 DOI: 10.3389/fphys.2018.00310] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2017] [Accepted: 03/14/2018] [Indexed: 11/13/2022] Open
Abstract
During a continuously increasing exercise workload (WL) a point will be reached at which arterial lactate accumulates rapidly. This so-called lactate threshold (LT) is associated with the maximal lactate steady state workload (MLSSW), the highest WL, at which arterial lactate concentration [LA] does not change. However, the physiological range in which the LT and the MLSSW occur has not been demonstrated directly. We used minor WL variations in the MLSSW range to assess arterial lactate kinetics in 278 treadmill and 148 bicycle ergometer exercise tests. At a certain workload, minimal further increment of running speed (0.1-0.15 m/s) or cycling power (7-10 W) caused a steep elevation of [LA] (0.9 ± 0.43 mM, maximum increase 2.4 mM), indicating LT achievement. This sharp [LA] increase was more pronounced when higher WL increments were used (0.1 vs. 0.30 m/s, P = 0.02; 0.15 vs. 0.30 m/s, P < 0.001; 7 vs. 15 W, P = 0.002; 10 vs. 15 W, P = 0.001). A subsequent workload reduction (0.1 m/s/7 W) stopped the [LA] increase indicating MLSSW realization. LT based determination of running speed (MLSSW) was highly reproducible on a day-to-day basis (r = 0.996, P < 0.001), valid in a 10 km constant velocity setting (r = 0.981, P < 0.001) and a half marathon race (r = 0.969, P < 0.001). These results demonstrate a fine-tuned regulation of exercise-related lactate metabolism, which can be reliably captured by assessing lactate kinetics at the MLSSW.
Collapse
Affiliation(s)
- Gernot O Hering
- Department of Sport and Health Science, University of Konstanz, Konstanz, Germany
| | - Ewald M Hennig
- Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, QLD, Australia
| | - Hartmut J Riehle
- Department of Sport and Health Science, University of Konstanz, Konstanz, Germany
| | - Jens Stepan
- Department of Sport and Health Science, University of Konstanz, Konstanz, Germany
| |
Collapse
|
40
|
Domínguez R, Maté-Muñoz JL, Cuenca E, García-Fernández P, Mata-Ordoñez F, Lozano-Estevan MC, Veiga-Herreros P, da Silva SF, Garnacho-Castaño MV. Effects of beetroot juice supplementation on intermittent high-intensity exercise efforts. J Int Soc Sports Nutr 2018; 15:2. [PMID: 29311764 PMCID: PMC5756374 DOI: 10.1186/s12970-017-0204-9] [Citation(s) in RCA: 68] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2017] [Accepted: 12/07/2017] [Indexed: 12/21/2022] Open
Abstract
Beetroot juice contains high levels of inorganic nitrate (NO3-) and its intake has proved effective at increasing blood nitric oxide (NO) concentrations. Given the effects of NO in promoting vasodilation and blood flow with beneficial impacts on muscle contraction, several studies have detected an ergogenic effect of beetroot juice supplementation on exercise efforts with high oxidative energy metabolism demands. However, only a scarce yet growing number of investigations have sought to assess the effects of this supplement on performance at high-intensity exercise. Here we review the few studies that have addressed this issue. The databases Dialnet, Elsevier, Medline, Pubmed and Web of Science were searched for articles in English, Portuguese and Spanish published from 2010 to March 31 to 2017 using the keywords: beet or beetroot or nitrate or nitrite and supplement or supplementation or nutrition or "sport nutrition" and exercise or sport or "physical activity" or effort or athlete. Nine articles fulfilling the inclusion criteria were identified. Results indicate that beetroot juice given as a single dose or over a few days may improve performance at intermittent, high-intensity efforts with short rest periods. The improvements observed were attributed to faster phosphocreatine resynthesis which could delay its depletion during repetitive exercise efforts. In addition, beetroot juice supplementation could improve muscle power output via a mechanism involving a faster muscle shortening velocity. The findings of some studies also suggested improved indicators of muscular fatigue, though the mechanism involved in this effect remains unclear.
Collapse
Affiliation(s)
- Raúl Domínguez
- Physical Activity and Sport Sciences, College of Health Sciences, Alfonso X El Sabio University, Madrid, Spain
| | - José Luis Maté-Muñoz
- Physical Activity and Sport Sciences, College of Health Sciences, Alfonso X El Sabio University, Madrid, Spain
| | - Eduardo Cuenca
- TecnoCampus. GRI-AFIRS, School of Health Sciences, Pompeu Fabra University, Mataró, Barcelona, Spain
| | - Pablo García-Fernández
- Physical Activity and Sport Sciences, College of Health Sciences, Alfonso X El Sabio University, Madrid, Spain
| | | | - María Carmen Lozano-Estevan
- Physical Activity and Sport Sciences, College of Health Sciences, Alfonso X El Sabio University, Madrid, Spain
| | - Pablo Veiga-Herreros
- Physical Activity and Sport Sciences, College of Health Sciences, Alfonso X El Sabio University, Madrid, Spain
| | - Sandro Fernandes da Silva
- Physical Activity and Sport Sciences, Physical Education Departament, University of Lavras, Lavras, Brazil
| | | |
Collapse
|
41
|
A Novel Electromyographic Approach to Estimate Fatigue Threshold in Maximum Incremental Strength Tests. Motor Control 2017; 22:170. [PMID: 28530475 DOI: 10.1123/mc.2016-0066] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Evaluation of muscular fatigue thresholds in athletes performing short-duration and explosive exercises is difficult because classic parameters do not suffer large variations. Therefore, the aim of this study was to develop a new method to estimate the fatigue threshold in single muscles. Our approach is based on electromyographic data recorded during a maximum incremental strength test until the one repetition maximum is reached. Ten men and 10 women performed a half-squat strength test consisting of five incremental intensities of one repetition maximum. Neither heart rate nor blood lactate concentrations showed significant differences at the various intensities tested. Surface electromyographic activities of vastus lateralis, vastus medialis, and rectus femoris were recorded, finding a break point corresponding to the fatigue threshold occurring in men at 70.74%, 71.48%, and 72.52% of one repetition maximum, respectively. In women, break-point values were 76.66% for vastus lateralis, 76.27% for vastus medialis, and 72.10% for rectus femoris. In conclusion, surface electromyography could be a useful, rapid, and noninvasive tool to determine the fatigue threshold of independent muscles during a maximal half-squat strength test.
Collapse
|
42
|
Kume D, Iguchi A, Endoh H. Accelerated point of muscle deoxygenation during the 20-m shuttle run test. Clin Physiol Funct Imaging 2017; 38:390-395. [PMID: 28414877 DOI: 10.1111/cpf.12426] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2016] [Accepted: 02/22/2017] [Indexed: 11/28/2022]
Abstract
This study examined whether the point of accelerated deoxygenation of active muscle occurs during the 20-m shuttle run test (20mSRT) and, if so, whether it is associated with exercise performance in the test. Twenty-nine male subjects performed the 20mSRT, and concentration changes in oxyhaemoglobin (ΔOxy-Hb) and deoxyhaemoglobin (ΔDeoxy-Hb) in the m. vastus lateralis were measured using a portable near-infrared spectroscopy device. The difference between the relative concentration changes in ΔOxy-Hb and ΔDeoxy-Hb (Δ[Oxy-Hb - Deoxy-Hb]) was regarded as the muscle oxygenation index. Group-averaged Δ[Oxy-Hb - Deoxy-Hb] showed progressive decrease during the test. However, among the individuals, we found an accelerated point of decrease in Δ[Oxy-Hb - Deoxy-Hb] in 20 subjects, which revealed that the laps at the accelerated point correlated with the total laps (r = 0·78). These results demonstrate that the accelerated deoxygenation of active muscle occurs during the 20mSRT, but not in all cases. Our findings also indicate that if the accelerated point of muscle deoxygenation occurs, the timing of its appearance is related to 20mSRT performance.
Collapse
Affiliation(s)
- Daisuke Kume
- Department of Integrated Arts and Science, National Institute of Technology, Okinawa College, Nago, Japan
| | - Akira Iguchi
- Department of Bioresources Engineering, National Institute of Technology, Okinawa College, Nago, Japan
| | - Hiroshi Endoh
- Department of Health and Physical Education, University of the Ryukyus, Okinawa, Japan
| |
Collapse
|
43
|
Jotta B, Coutinho ABB, Pino AV, Souza MN. Lactate threshold by muscle electrical impedance in professional rowers. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2017; 88:045105. [PMID: 28456219 DOI: 10.1063/1.4979072] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Lactate threshold (LT) is one of the physiological parameters usually used in rowing sport training prescription because it indicates the transitions from aerobic to anaerobic metabolism. Assessment of LT is classically based on a series of values of blood lactate concentrations obtained during progressive exercise tests and thus has an invasive aspect. The feasibility of noninvasive LT estimative through bioelectrical impedance spectroscopy (BIS) data collected in thigh muscles during rowing ergometer exercise tests was investigated. Nineteen professional rowers, age 19 (mean) ± 4.8 (standard deviation) yr, height 187.3 ± 6.6 cm, body mass 83 ± 7.7 kg, and training experience of 7 ± 4 yr, were evaluated in a rowing ergometer progressive test with paired measures of blood lactate concentration and BIS in thigh muscles. Bioelectrical impedance data were obtained by using a bipolar method of spectroscopy based on the current response to a voltage step. An electrical model was used to interpret BIS data and to derive parameters that were investigated to estimate LT noninvasively. From the serial blood lactate measurements, LT was also determined through Dmax method (LTDmax). The zero crossing of the second derivative of kinetic of the capacitance electrode (Ce), one of the BIS parameters, was used to estimate LT. The agreement between the LT estimates through BIS (LTBIS) and through Dmax method (LTDmax) was evaluated using Bland-Altman plots, leading to a mean difference between the estimates of just 0.07 W and a Pearson correlation coefficient r = 0.85. This result supports the utilization of the proposed method based on BIS parameters for estimating noninvasively the lactate threshold in rowing.
Collapse
Affiliation(s)
- B Jotta
- Biomedical Engineering Program, Universidade Federal do Rio de Janeiro/COPPE, Rio de Janeiro 21941-914, Brazil
| | - A B B Coutinho
- Biomedical Engineering Program, Universidade Federal do Rio de Janeiro/COPPE, Rio de Janeiro 21941-914, Brazil
| | - A V Pino
- Biomedical Engineering Program, Universidade Federal do Rio de Janeiro/COPPE, Rio de Janeiro 21941-914, Brazil
| | - M N Souza
- Biomedical Engineering Program, Universidade Federal do Rio de Janeiro/COPPE, Rio de Janeiro 21941-914, Brazil
| |
Collapse
|
44
|
Domínguez R, Cuenca E, Maté-Muñoz JL, García-Fernández P, Serra-Paya N, Estevan MCL, Herreros PV, Garnacho-Castaño MV. Effects of Beetroot Juice Supplementation on Cardiorespiratory Endurance in Athletes. A Systematic Review. Nutrients 2017; 9:nu9010043. [PMID: 28067808 PMCID: PMC5295087 DOI: 10.3390/nu9010043] [Citation(s) in RCA: 112] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2016] [Revised: 12/24/2016] [Accepted: 12/30/2016] [Indexed: 01/08/2023] Open
Abstract
Athletes use nutritional supplementation to enhance the effects of training and achieve improvements in their athletic performance. Beetroot juice increases levels of nitric oxide (NO), which serves multiple functions related to increased blood flow, gas exchange, mitochondrial biogenesis and efficiency, and strengthening of muscle contraction. These biomarker improvements indicate that supplementation with beetroot juice could have ergogenic effects on cardiorespiratory endurance that would benefit athletic performance. The aim of this literature review was to determine the effects of beetroot juice supplementation and the combination of beetroot juice with other supplements on cardiorespiratory endurance in athletes. A keyword search of DialNet, MedLine, PubMed, Scopus and Web of Science databases covered publications from 2010 to 2016. After excluding reviews/meta-analyses, animal studies, inaccessible full-text, and studies that did not supplement with beetroot juice and adequately assess cardiorespiratory endurance, 23 articles were selected for analysis. The available results suggest that supplementation with beetroot juice can improve cardiorespiratory endurance in athletes by increasing efficiency, which improves performance at various distances, increases time to exhaustion at submaximal intensities, and may improve the cardiorespiratory performance at anaerobic threshold intensities and maximum oxygen uptake (VO2max). Although the literature shows contradictory data, the findings of other studies lead us to hypothesize that supplementing with beetroot juice could mitigate the ergolytic effects of hypoxia on cardiorespiratory endurance in athletes. It cannot be stated that the combination of beetroot juice with other supplements has a positive or negative effect on cardiorespiratory endurance, but it is possible that the effects of supplementation with beetroot juice can be undermined by interaction with other supplements such as caffeine.
Collapse
Affiliation(s)
- Raúl Domínguez
- College of Health Sciences, University Alfonso X El Sabio University, Madrid 29651, Spain.
| | - Eduardo Cuenca
- Tecnocampus, College of Health Sciences, University of Pompeu Fabra, Mataró-Maresme, Barcelona 08302 Spain.
| | - José Luis Maté-Muñoz
- College of Health Sciences, University Alfonso X El Sabio University, Madrid 29651, Spain.
| | - Pablo García-Fernández
- College of Health Sciences, University Alfonso X El Sabio University, Madrid 29651, Spain.
| | - Noemí Serra-Paya
- Tecnocampus, College of Health Sciences, University of Pompeu Fabra, Mataró-Maresme, Barcelona 08302 Spain.
| | | | - Pablo Veiga Herreros
- College of Health Sciences, University Alfonso X El Sabio University, Madrid 29651, Spain.
| | | |
Collapse
|
45
|
Sasaki K, Kimura T, Kojima S, Higuchi H. The temporal relationship of thresholds between muscle activity and ventilation during bicycle ramp exercise in community dwelling elderly males. J Phys Ther Sci 2016; 28:3213-3219. [PMID: 27942152 PMCID: PMC5140832 DOI: 10.1589/jpts.28.3213] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2016] [Accepted: 07/29/2016] [Indexed: 11/24/2022] Open
Abstract
[Purpose] To compare the appearance time of the ventilatory threshold point and the electromyographic threshold in the activity of the vastus lateralis, rectus femoris, biceps femoris long head and gastrocnemius lateral head muscles during ramp cycling exercise in elderly males. [Subjects and Methods] Eleven community dwelling elderly males participated in this study. Subjects performed exercise testing with an expiratory gas analyzer and surface electromyography to evaluate the tested muscle activities during ramp exercise. [Results] The electromyographic threshold for rectus femoris was not valid because the slope after electromyographic threshold was not significant as compared to that before electromyographic threshold. The slope of the regression line for vastus lateralis was significantly decreased after electromyographic threshold while biceps femoris and gastrocnemius were increased. The electromyographic threshold appearance times for vastus lateralis and gastrocnemius were significantly earlier than ventilatory threshold point. There were no difference in electromyographic threshold appearance times among three muscles. [Conclusion] These results suggest that the increase in the slope of the regression line after electromyographic threshold for vastus lateralis was decreased, possibly indicating to postpone muscular fatigue resulting from the activation of biceps femoris and gastrocnemius as biarticular antagonists. This recruitment pattern might be an elderly-specific strategy.
Collapse
Affiliation(s)
- Kentaro Sasaki
- Department of Physical Therapy, Kinjo University, Japan; Graduate School of Health Sciences (Division of Distance Education), Kyushu University of Health and Welfare, Japan
| | - Tsuyoshi Kimura
- Department of Social Welfare, Faculty of Social Welfare, Kinjo University, Japan
| | | | - Hiroyuki Higuchi
- Graduate School of Health Sciences (Division of Distance Education), Kyushu University of Health and Welfare, Japan
| |
Collapse
|
46
|
Leprêtre PM, Ghannem M, Delanaud S, Porcher T, Barnabé A, Gaillard L, Jaunet N, Weissland T. [Is there a disassociation of ventilatory and electromyographic thresholds in patients with heart disease during a graded cycling exercise?]. Ann Cardiol Angeiol (Paris) 2016; 65:306-310. [PMID: 27697301 DOI: 10.1016/j.ancard.2016.09.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2016] [Accepted: 09/02/2016] [Indexed: 06/06/2023]
Abstract
UNLABELLED Exercise prescription was generally based on the determination of ventilatory thresholds (VT1, VT2) during cardiopulmonary exercise testing (CPX). Changes in surface electromyographic activity (EMGth1, EMGth2) were also related to VT1 and VT2 in healthy subjects. OBJECTIVE To observe the occurrence of EMGth1 and EMGth2 and whether these events accompany VT1 and VT2 during CPX in cardiac patients (CP). METHOD Thirty-four CP (62.1±7.3years, 172.1±6.3cm, 81.3±15.3kg, BMI: 27.3±4.1) performed a cycle CPX at a 60-rpm cadence. VT1 was determined as the breakpoint in the curve of carbon dioxide output against oxygen uptake plot (V-slope method). VT2 was defined as the point at which the ratio of minute ventilation to carbon dioxide output starts to increase. The root mean square of electromyogram (rms-EMG) was on-line calculated from the real time bipolar surface electromyographic signals recorded from the vastus lateralis. EMGth1 and EMGth2 were defined as the first and the second breakpoints in the rms-EMG-power output relationship. RESULTS Peak values of oxygen uptake (16.3±4.6mL·min-1·kg-1) and heart rate (106.7±13.8bpm) were reached at 112.9±38.5w (PMT). VT1 and VT2 occurred at 71.1±25.9w (62.5±5.5% PMT) and 87.9±28.6w (78.0±5.1% PMT). All subjects presented two breakpoints in the rms-EMG curve, EMGth1 at 68.0±24.7w and EMGth2 at 88.5±30.1w, i.e. 60.0±7.6 and 78.6±5.0% of PMT. EMGth1 occurred significantly before VT1 (P=0.004, small effect size). No significant difference was observed between EMGth2 and VT2 (P=0.13, small effect size). CONCLUSION The EMGth1 occurrence before VT1 suggested a role of skeletal muscle conditioning on ventilatory responses, which should be taken into account in cardiac rehabilitation program prescription.
Collapse
Affiliation(s)
- P-M Leprêtre
- EA-3300, laboratoire « adaptations physiologiques à l'exercice et réadaptation à l'effort », UFR-STAPS, université de Picardie-Jules-Verne, campus Sud, allée Paschal-Grousset, 80025 Amiens cedex 1, France.
| | - M Ghannem
- EA-3300, laboratoire « adaptations physiologiques à l'exercice et réadaptation à l'effort », UFR-STAPS, université de Picardie-Jules-Verne, campus Sud, allée Paschal-Grousset, 80025 Amiens cedex 1, France; Centre de réadaptation cardiaque Léopold-Bellan, château d'Ollencourt, 60170 Tracy-Le-Mont, France
| | - S Delanaud
- Laboratoire périnatalité et risques toxiques PERITOX - UMI_01, unité mixte INERIS, CHU Amiens-Picardie, 80480 Salouël, France; Institut d'ingénierie de la santé (2IS), UFR de médecine, université de Picardie-Jules-Verne, 80000 Amiens, France
| | - T Porcher
- Centre de réadaptation cardiaque Léopold-Bellan, château d'Ollencourt, 60170 Tracy-Le-Mont, France
| | - A Barnabé
- Institut d'ingénierie de la santé (2IS), UFR de médecine, université de Picardie-Jules-Verne, 80000 Amiens, France
| | - L Gaillard
- Centre de réadaptation cardiaque Léopold-Bellan, château d'Ollencourt, 60170 Tracy-Le-Mont, France; Institut d'ingénierie de la santé (2IS), UFR de médecine, université de Picardie-Jules-Verne, 80000 Amiens, France
| | - N Jaunet
- Centre de réadaptation cardiaque Léopold-Bellan, château d'Ollencourt, 60170 Tracy-Le-Mont, France
| | - T Weissland
- EA-3300, laboratoire « adaptations physiologiques à l'exercice et réadaptation à l'effort », UFR-STAPS, université de Picardie-Jules-Verne, campus Sud, allée Paschal-Grousset, 80025 Amiens cedex 1, France; Institut d'ingénierie de la santé (2IS), UFR de médecine, université de Picardie-Jules-Verne, 80000 Amiens, France
| |
Collapse
|
47
|
Miramonti AA, Stout JR, Fukuda DH, Robinson EH, Wang R, La Monica MB, Hoffman JR. Effects of 4 Weeks of High-Intensity Interval Training and β-Hydroxy-β-Methylbutyric Free Acid Supplementation on the Onset of Neuromuscular Fatigue. J Strength Cond Res 2016; 30:626-34. [PMID: 26418369 DOI: 10.1519/jsc.0000000000001140] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
This study investigated the effects of high-intensity interval training (HIIT) and β-hydroxy-β-methylbutyric free acid (HMB) supplementation on physical working capacity at the onset of neuromuscular fatigue threshold (PWC(FT)). Thirty-seven participants (22 men, 15 women; 22.8 ± 3.4 years) completed an incremental cycle ergometer test (graded exercise test [GXT]); electromyographic amplitude from the right vastus lateralis was recorded. Assessments occurred preceding (PRE) and after 4 weeks of supplementation (POST). Participants were randomly assigned to control (C, n = 9), placebo (P, n = 14), or supplementation (S, n = 14) groups. Both P and S completed 12 HIIT sessions, whereas C maintained normal diet and activity patterns. The PWC(FT) (W) was determined using the maximal perpendicular distance (D(MAX)) method. Electromyographic amplitude (μVrms) over time was used to generate a cubic regression. Onset of fatigue (TF) was the x-value of the point on the regression that was at D(MAX) from a line between the first and last data points. The PWC(FT) was estimated using TF and GXT power-output increments. The 2-way analysis of variance (ANOVA) (group × time) resulted in a significant interaction for PWC(FT) (F = 6.69, p = 0.004). Post hoc analysis with 1-way ANOVA resulted in no difference in PWC(FT) among groups at PRE (F = 0.87, p = 0.43); however, a difference in PWC(FT) was shown for POST (F = 5.46, p = 0.009). Post hoc analysis among POST values revealed significant differences between S and both P (p = 0.034) and C (p = 0.003). No differences (p = 0.226) were noted between P and C. Paired samples t-tests detected significant changes after HIIT for S (p < 0.001) and P (p = 0.016), but no change in C (p = 0.473). High-intensity interval training increased PWC(FT), but HMB with HIIT was more effective than HIIT alone. Furthermore, it seems that adding HMB supplementation with HIIT in untrained men and women may further improve endurance performance measures.
Collapse
Affiliation(s)
- Amelia A Miramonti
- Institute of Exercise Physiology and Wellness, Educational and Human Sciences, University of Central Florida, Orlando, Florida
| | | | | | | | | | | | | |
Collapse
|
48
|
Zoppirolli C, Pellegrini B, Modena R, Savoldelli A, Bortolan L, Schena F. Changes in upper and lower body muscle involvement at increasing double poling velocities: an ecological study. Scand J Med Sci Sports 2016; 27:1292-1299. [PMID: 27726202 DOI: 10.1111/sms.12783] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/06/2016] [Indexed: 11/29/2022]
Abstract
This study evaluated muscle activity changes in different body compartments during on-snow double poling at increasing velocities. 21 well-trained, male cross-country skiers performed five 3-min double poling trials on a snowy track at 15, 16.5, 18, 19.5, and 21 km/h (set by an audio-pace system). A sixth trial was performed by maintaining a constant maximal speed. Actual skiing velocities were verified using a photocell system. Only 11 subjects met the pre-defined inclusion criteria during the trials and were included in the data analysis. Electromyographical signals from seven muscles, wrist acceleration and heart rate during the last minute of each trial were recorded. Cycle and poling times were measured from acceleration signals; mean muscular activation over a cycle was calculated for each muscle. With increasing double poling velocities from aerobic to maximal intensity (from 65% to 100% of maximal heart rate), upper limb muscles activation was maintained constant (P > 0.05), while trunk and lower limb involvement increased significantly (P < 0.01) with a linear trend. Rectus abdominis and rectus femoris muscles showed the higher rate of change. Trunk and lower limbs provide a progressively greater contribution to the propulsion when increasing double poling velocities are performed, to support the limited capacity of exercise response of upper body muscles. The remarkable rate of involvement of the muscles near the core region of the body becomes strategic to cope with the increased demands of propulsive power.
Collapse
Affiliation(s)
- C Zoppirolli
- CeRiSM (Research Center Sport Mountain & Health), Rovereto, Italy.,Neurological, Biomedical and Movement Sciences Department, University of Verona, Rovereto, Italy
| | - B Pellegrini
- CeRiSM (Research Center Sport Mountain & Health), Rovereto, Italy.,Neurological, Biomedical and Movement Sciences Department, University of Verona, Rovereto, Italy
| | - R Modena
- CeRiSM (Research Center Sport Mountain & Health), Rovereto, Italy.,Neurological, Biomedical and Movement Sciences Department, University of Verona, Rovereto, Italy
| | - A Savoldelli
- CeRiSM (Research Center Sport Mountain & Health), Rovereto, Italy.,Neurological, Biomedical and Movement Sciences Department, University of Verona, Rovereto, Italy
| | - L Bortolan
- CeRiSM (Research Center Sport Mountain & Health), Rovereto, Italy.,Neurological, Biomedical and Movement Sciences Department, University of Verona, Rovereto, Italy
| | - F Schena
- CeRiSM (Research Center Sport Mountain & Health), Rovereto, Italy.,Neurological, Biomedical and Movement Sciences Department, University of Verona, Rovereto, Italy
| |
Collapse
|
49
|
Pallarés JG, Morán-Navarro R, Ortega JF, Fernández-Elías VE, Mora-Rodriguez R. Validity and Reliability of Ventilatory and Blood Lactate Thresholds in Well-Trained Cyclists. PLoS One 2016; 11:e0163389. [PMID: 27657502 PMCID: PMC5033582 DOI: 10.1371/journal.pone.0163389] [Citation(s) in RCA: 91] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Accepted: 09/06/2016] [Indexed: 11/18/2022] Open
Abstract
PURPOSE The purpose of this study was to determine, i) the reliability of blood lactate and ventilatory-based thresholds, ii) the lactate threshold that corresponds with each ventilatory threshold (VT1 and VT2) and with maximal lactate steady state test (MLSS) as a proxy of cycling performance. METHODS Fourteen aerobically-trained male cyclists ([Formula: see text] 62.1±4.6 ml·kg-1·min-1) performed two graded exercise tests (50 W warm-up followed by 25 W·min-1) to exhaustion. Blood lactate, [Formula: see text] and [Formula: see text] data were collected at every stage. Workloads at VT1 (rise in [Formula: see text];) and VT2 (rise in [Formula: see text]) were compared with workloads at lactate thresholds. Several continuous tests were needed to detect the MLSS workload. Agreement and differences among tests were assessed with ANOVA, ICC and Bland-Altman. Reliability of each test was evaluated using ICC, CV and Bland-Altman plots. RESULTS Workloads at lactate threshold (LT) and LT+2.0 mMol·L-1 matched the ones for VT1 and VT2, respectively (p = 0.147 and 0.539; r = 0.72 and 0.80; Bias = -13.6 and 2.8, respectively). Furthermore, workload at LT+0.5 mMol·L-1 coincided with MLSS workload (p = 0.449; r = 0.78; Bias = -4.5). Lactate threshold tests had high reliability (CV = 3.4-3.7%; r = 0.85-0.89; Bias = -2.1-3.0) except for DMAX method (CV = 10.3%; r = 0.57; Bias = 15.4). Ventilatory thresholds show high reliability (CV = 1.6%-3.5%; r = 0.90-0.96; Bias = -1.8-2.9) except for RER = 1 and V-Slope (CV = 5.0-6.4%; r = 0.79; Bias = -5.6-12.4). CONCLUSIONS Lactate threshold tests can be a valid and reliable alternative to ventilatory thresholds to identify the workloads at the transition from aerobic to anaerobic metabolism.
Collapse
Affiliation(s)
- Jesús G. Pallarés
- University of Castilla-La Mancha, Exercise Physiology Laboratory at Toledo, Toledo, Spain
- Human Performance and Sports Science Laboratory, Faculty of Sport Sciences, University of Murcia, Murcia, Spain
| | - Ricardo Morán-Navarro
- University of Castilla-La Mancha, Exercise Physiology Laboratory at Toledo, Toledo, Spain
- Human Performance and Sports Science Laboratory, Faculty of Sport Sciences, University of Murcia, Murcia, Spain
| | - Juan Fernando Ortega
- University of Castilla-La Mancha, Exercise Physiology Laboratory at Toledo, Toledo, Spain
| | | | - Ricardo Mora-Rodriguez
- University of Castilla-La Mancha, Exercise Physiology Laboratory at Toledo, Toledo, Spain
- * E-mail:
| |
Collapse
|
50
|
Detecting fatigue thresholds from electromyographic signals: A systematic review on approaches and methodologies. J Electromyogr Kinesiol 2016; 30:216-30. [PMID: 27529668 DOI: 10.1016/j.jelekin.2016.08.002] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2016] [Revised: 07/26/2016] [Accepted: 08/01/2016] [Indexed: 11/23/2022] Open
Abstract
The aim of the current paper was to systematically review the relevant existing electromyographic threshold concepts within the literature. The electronic databases MEDLINE and SCOPUS were screened for papers published between January 1980 and April 2015 including the keywords: neuromuscular fatigue threshold, anaerobic threshold, electromyographic threshold, muscular fatigue, aerobic-anaerobictransition, ventilatory threshold, exercise testing, and cycle-ergometer. 32 articles were assessed with regard to their electromyographic methodologies, description of results, statistical analysis and test protocols. Only one article was of very good quality. 21 were of good quality and two articles were of very low quality. The review process revealed that: (i) there is consistent evidence of one or two non-linear increases of EMG that might reflect the additional recruitment of motor units (MU) or different fiber types during fatiguing cycle ergometer exercise, (ii) most studies reported no statistically significant difference between electromyographic and metabolic thresholds, (iii) one minute protocols with increments between 10 and 25W appear most appropriate to detect muscular threshold, (iv) threshold detection from the vastus medialis, vastus lateralis, and rectus femoris is recommended, and (v) there is a great variety in study protocols, measurement techniques, and data processing. Therefore, we recommend further research and standardization in the detection of EMGTs.
Collapse
|