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Pacing strategies during repeated maximal voluntary contractions
I Halperin1, S J Aboodarda, F A Basset
1School of Human Kinetics and Recreation, Memorial University of Newfoundland, St. John's, NL, A1C 5S7, Canada.
European Journal of Applied Physiology
|March 25, 2014
Summary
Knowing the number of maximal voluntary contractions (MVCs) influences performance. Deception about MVC count led to higher force and EMG, suggesting altered pacing strategies in fatiguing protocols.
Area of Science:
- Exercise Physiology
- Neuromuscular Physiology
Background:
- Pacing strategies are known in continuous exercise.
- Pacing during repeated maximal voluntary contractions (MVCs) is not well understood.
Purpose of the Study:
- To investigate if knowledge of the number of MVCs affects force and electromyography (EMG) during fatiguing protocols.
- To examine pacing strategies during repeated MVCs.
Main Methods:
- Thirty male subjects performed 12 MVCs under three conditions: control (known number), unknown (uninformed), and deception (initially told fewer MVCs).
- Force and biceps EMG were measured throughout the fatiguing protocols.
Main Results:
- Subjects exerted greater force and biceps EMG in the deception condition compared to the unknown condition during the first six MVCs.
- In all conditions, force increased in the final MVC (#12) compared to the preceding one (#11).
Conclusions:
- Anticipation of the number of MVCs influences pacing strategies.
- The study questions the assumption of maximal effort throughout repeated MVC protocols.
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