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The Dynamics of Locomotor Neuromuscular Fatigue during Ramp-Incremental Cycling to Intolerance
Molly M Baldwin1, Matt R Chadwick1, Alan P Benson1
1School of Biomedical Sciences, Faculty of Biological Sciences & Multidisciplinary Cardiovascular Research Centre, University of Leeds, Leeds, UNITED KINGDOM.
Medicine and Science in Sports and Exercise
|March 11, 2024
Summary
This study shows that neuromuscular performance declines progressively during ramp-incremental exercise, particularly above the gas exchange threshold. Peak power and muscle excitation decrease, indicating task-specific fatigue during whole-body cycling.
Area of Science:
- Exercise Physiology
- Neuromuscular Physiology
- Sports Science
Background:
- Traditional neuromuscular fatigue assessments lack task-specificity for dynamic whole-body exercise.
- Characterizing neuromuscular performance decline during ramp-incremental (RI) exercise is crucial.
Purpose of the Study:
- To characterize the dynamics of neuromuscular performance decline during RI cycle ergometry.
- To investigate the relationship between neuromuscular decline and exercise intensity.
Main Methods:
- Eleven healthy participants underwent RI cycle ergometry to exhaustion.
- Peak isokinetic power (Piso) and electromyography (EMG) were measured intermittently during exercise.
- Pulmonary gas exchange was monitored throughout.
Main Results:
- Peak isokinetic power (Piso) significantly decreased from baseline (832 W) to exhaustion (349 W).
- Piso and peak muscle excitation (EMG) declined progressively above the gas exchange threshold (GET).
- The reduction in Piso preceded the reduction in EMG.
Conclusions:
- Neuromuscular performance decline during RI exercise is intensity-dependent.
- The observed fatigue dynamics align with metabolic and traditional fatigue responses.
- Interleaved assessments effectively characterize neuromuscular fatigue during dynamic exercise.
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