Evidence for neuromuscular fatigue during high-intensity cycling in warm, humid conditions

Derek Kay, Francesco Marino, Jack Cannon, Alan St clair gibson, Mike Lambert, Timothy Noakes

Research output: Contribution to journalArticle

149 Citations (Scopus)

Abstract

Further investigations in which changes in multiple physiological systems are assessed systematically are required so that the underlying mechanisms related to the development of fatigue during normal dynamic movements such as cycling can be more clearly delineated.The purpose of this study was to examine and describe the neuromuscular changes associated with fatigue using a self-paced cycling protocol of 60-min duration, under warm, humid conditions. Eleven subjects [mean (SE) age 21.8 (0.8)'years; height 174.9 (3.0)'cm; body mass 74.8 (2.7)'kg; maximum oxygen consumption 50.3 (1.8)'ml'·'kg'·'min'1] performed one 60-min self-paced cycling time trial punctuated with six 1-min 'all out' sprints at 10-min intervals, while 4 subjects repeated the trial for the purpose of determining reproducibility. Power output, integrated electromyographic signal (IEMG), and mean percentile frequency shifts (MPFS) were recorded at the mid-point of each sprint. There were no differences between trials for EMG variables, distance cycled, mean heart rate, and subjective rating of perceived exertion for the subjects who repeated the trial (n=4). The results from the repeated trials suggest that neuromuscular responses to self-paced cycling are reproducible between trials. The mean heart rate for the 11 subjects was 163.6 (0.71)'beats'·'min'1. Values for power output and IEMG expressed as a percentage of that recorded for the initial sprint decreased during sprints 2'5, with normalised values being 94%, 91%, 87% and 87%, respectively, and 71%, 71%, 73%, and 77%, respectively. However, during the final sprint normalised power output and IEMG increased to 94% and 90% of initial values, respectively. MPFS displayed an increase with time; however, this was not significant (P=0.06). The main finding of this investigation is the ability of subjects to return power output to near initial values during the final of six maximal effort sprints that were included as part of a self-paced cycling protocol. This appears to be due to a combination of changes in neuromuscular recruitment, central or peripheral control systems, or the EMG signal itself.
Original languageEnglish
Pages (from-to)115-121
Number of pages7
JournalEuropean Journal of Applied Physiology
Volume84
Issue number1/2
DOIs
Publication statusPublished - 2001

Fingerprint

Fatigue
Heart Rate
Oxygen Consumption

Cite this

Kay, Derek ; Marino, Francesco ; Cannon, Jack ; St clair gibson, Alan ; Lambert, Mike ; Noakes, Timothy. / Evidence for neuromuscular fatigue during high-intensity cycling in warm, humid conditions. In: European Journal of Applied Physiology. 2001 ; Vol. 84, No. 1/2. pp. 115-121.
@article{512366b5dca64120840c32209576db1d,
title = "Evidence for neuromuscular fatigue during high-intensity cycling in warm, humid conditions",
abstract = "Further investigations in which changes in multiple physiological systems are assessed systematically are required so that the underlying mechanisms related to the development of fatigue during normal dynamic movements such as cycling can be more clearly delineated.The purpose of this study was to examine and describe the neuromuscular changes associated with fatigue using a self-paced cycling protocol of 60-min duration, under warm, humid conditions. Eleven subjects [mean (SE) age 21.8 (0.8)'years; height 174.9 (3.0)'cm; body mass 74.8 (2.7)'kg; maximum oxygen consumption 50.3 (1.8)'ml'{\^A}·'kg'{\^A}·'min'1] performed one 60-min self-paced cycling time trial punctuated with six 1-min 'all out' sprints at 10-min intervals, while 4 subjects repeated the trial for the purpose of determining reproducibility. Power output, integrated electromyographic signal (IEMG), and mean percentile frequency shifts (MPFS) were recorded at the mid-point of each sprint. There were no differences between trials for EMG variables, distance cycled, mean heart rate, and subjective rating of perceived exertion for the subjects who repeated the trial (n=4). The results from the repeated trials suggest that neuromuscular responses to self-paced cycling are reproducible between trials. The mean heart rate for the 11 subjects was 163.6 (0.71)'beats'{\^A}·'min'1. Values for power output and IEMG expressed as a percentage of that recorded for the initial sprint decreased during sprints 2'5, with normalised values being 94{\%}, 91{\%}, 87{\%} and 87{\%}, respectively, and 71{\%}, 71{\%}, 73{\%}, and 77{\%}, respectively. However, during the final sprint normalised power output and IEMG increased to 94{\%} and 90{\%} of initial values, respectively. MPFS displayed an increase with time; however, this was not significant (P=0.06). The main finding of this investigation is the ability of subjects to return power output to near initial values during the final of six maximal effort sprints that were included as part of a self-paced cycling protocol. This appears to be due to a combination of changes in neuromuscular recruitment, central or peripheral control systems, or the EMG signal itself.",
author = "Derek Kay and Francesco Marino and Jack Cannon and {St clair gibson}, Alan and Mike Lambert and Timothy Noakes",
note = "Imported on 12 Apr 2017 - DigiTool details were: Journal title (773t) = European Journal of Applied Physiology. ISSNs: 1439-6319;",
year = "2001",
doi = "10.1007/s004210000340",
language = "English",
volume = "84",
pages = "115--121",
journal = "European Journal of Applied Physiology and Occupational Physiology",
issn = "1439-6319",
publisher = "Springer-Verlag London Ltd.",
number = "1/2",

}

Evidence for neuromuscular fatigue during high-intensity cycling in warm, humid conditions. / Kay, Derek; Marino, Francesco; Cannon, Jack; St clair gibson, Alan; Lambert, Mike; Noakes, Timothy.

In: European Journal of Applied Physiology, Vol. 84, No. 1/2, 2001, p. 115-121.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Evidence for neuromuscular fatigue during high-intensity cycling in warm, humid conditions

AU - Kay, Derek

AU - Marino, Francesco

AU - Cannon, Jack

AU - St clair gibson, Alan

AU - Lambert, Mike

AU - Noakes, Timothy

N1 - Imported on 12 Apr 2017 - DigiTool details were: Journal title (773t) = European Journal of Applied Physiology. ISSNs: 1439-6319;

PY - 2001

Y1 - 2001

N2 - Further investigations in which changes in multiple physiological systems are assessed systematically are required so that the underlying mechanisms related to the development of fatigue during normal dynamic movements such as cycling can be more clearly delineated.The purpose of this study was to examine and describe the neuromuscular changes associated with fatigue using a self-paced cycling protocol of 60-min duration, under warm, humid conditions. Eleven subjects [mean (SE) age 21.8 (0.8)'years; height 174.9 (3.0)'cm; body mass 74.8 (2.7)'kg; maximum oxygen consumption 50.3 (1.8)'ml'·'kg'·'min'1] performed one 60-min self-paced cycling time trial punctuated with six 1-min 'all out' sprints at 10-min intervals, while 4 subjects repeated the trial for the purpose of determining reproducibility. Power output, integrated electromyographic signal (IEMG), and mean percentile frequency shifts (MPFS) were recorded at the mid-point of each sprint. There were no differences between trials for EMG variables, distance cycled, mean heart rate, and subjective rating of perceived exertion for the subjects who repeated the trial (n=4). The results from the repeated trials suggest that neuromuscular responses to self-paced cycling are reproducible between trials. The mean heart rate for the 11 subjects was 163.6 (0.71)'beats'·'min'1. Values for power output and IEMG expressed as a percentage of that recorded for the initial sprint decreased during sprints 2'5, with normalised values being 94%, 91%, 87% and 87%, respectively, and 71%, 71%, 73%, and 77%, respectively. However, during the final sprint normalised power output and IEMG increased to 94% and 90% of initial values, respectively. MPFS displayed an increase with time; however, this was not significant (P=0.06). The main finding of this investigation is the ability of subjects to return power output to near initial values during the final of six maximal effort sprints that were included as part of a self-paced cycling protocol. This appears to be due to a combination of changes in neuromuscular recruitment, central or peripheral control systems, or the EMG signal itself.

AB - Further investigations in which changes in multiple physiological systems are assessed systematically are required so that the underlying mechanisms related to the development of fatigue during normal dynamic movements such as cycling can be more clearly delineated.The purpose of this study was to examine and describe the neuromuscular changes associated with fatigue using a self-paced cycling protocol of 60-min duration, under warm, humid conditions. Eleven subjects [mean (SE) age 21.8 (0.8)'years; height 174.9 (3.0)'cm; body mass 74.8 (2.7)'kg; maximum oxygen consumption 50.3 (1.8)'ml'·'kg'·'min'1] performed one 60-min self-paced cycling time trial punctuated with six 1-min 'all out' sprints at 10-min intervals, while 4 subjects repeated the trial for the purpose of determining reproducibility. Power output, integrated electromyographic signal (IEMG), and mean percentile frequency shifts (MPFS) were recorded at the mid-point of each sprint. There were no differences between trials for EMG variables, distance cycled, mean heart rate, and subjective rating of perceived exertion for the subjects who repeated the trial (n=4). The results from the repeated trials suggest that neuromuscular responses to self-paced cycling are reproducible between trials. The mean heart rate for the 11 subjects was 163.6 (0.71)'beats'·'min'1. Values for power output and IEMG expressed as a percentage of that recorded for the initial sprint decreased during sprints 2'5, with normalised values being 94%, 91%, 87% and 87%, respectively, and 71%, 71%, 73%, and 77%, respectively. However, during the final sprint normalised power output and IEMG increased to 94% and 90% of initial values, respectively. MPFS displayed an increase with time; however, this was not significant (P=0.06). The main finding of this investigation is the ability of subjects to return power output to near initial values during the final of six maximal effort sprints that were included as part of a self-paced cycling protocol. This appears to be due to a combination of changes in neuromuscular recruitment, central or peripheral control systems, or the EMG signal itself.

U2 - 10.1007/s004210000340

DO - 10.1007/s004210000340

M3 - Article

VL - 84

SP - 115

EP - 121

JO - European Journal of Applied Physiology and Occupational Physiology

JF - European Journal of Applied Physiology and Occupational Physiology

SN - 1439-6319

IS - 1/2

ER -