Joint-specific power-pedaling rate relationships during maximal cycling
John McDaniel1, N Scott Behjani, Steven J Elmer
1Department of Exercise Science, Kent State University, Kent, OH.
Journal of Applied Biomechanics
|March 11, 2014
Summary
The way cyclists generate power changes with pedaling rate. Hip and knee joints contribute more power at higher rates, while ankle power decreases, influencing the overall power-pedaling relationship.
Area of Science:
- Sports Science
- Biomechanics
- Human Physiology
Background:
- Previous research established power-pedaling rate relationships in maximal cycling.
- However, the specific contributions of individual joint powers to overall pedal power across different pedaling rates remained uninvestigated.
Purpose of the Study:
- To determine the absolute and relative contributions of joint-specific powers to pedal power during maximal cycling.
- To analyze how pedaling rate influences these joint-specific power contributions, joint velocities, and joint excursions.
Main Methods:
- Ten cyclists completed maximal 3-second cycling trials at five different pedaling rates (60, 90, 120, 150, 180 rpm).
- Joint-specific powers, velocities, and excursions were measured and averaged over complete pedal cycles and different phases (extension/flexion).
- Statistical analyses, including regression and repeated-measures ANOVA, were used to assess the effects of pedaling rate.
Main Results:
- Relative ankle plantar flexion power decreased significantly with increasing pedaling rate (25% to 8%).
- Relative hip extension power (41% to 59%) and knee flexion power (34% to 49%) significantly increased with higher pedaling rates.
- Ankle joint excursion decreased, while hip joint excursion increased as pedaling rate increased; knee extension power remained constant.
Conclusions:
- The observed quadratic power-pedaling rate relationship is a result of differing joint-specific power contributions across pedaling rates.
- These variations are likely influenced by biomechanical factors such as muscle architecture, limb morphology, and motor control strategies.
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