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Force-velocity and power-velocity relationships during maximal short-term rowing ergometry
Robert C Sprague1, James C Martin, Christopher J Davidson
1Department of Kinesiology and Health Education, The University of Texas at Austin, Austin, TX, USA.
Medicine and Science in Sports and Exercise
|February 6, 2007
Summary
Maximal rowing power-velocity relationships were characterized, revealing optimal velocities for peak power output. Duty cycle significantly influences rowing power, highlighting its importance for performance.
Area of Science:
- Sports Science
- Biomechanics
- Human Physiology
Background:
- Maximal rowing power-velocity relationships with distinct ascending/descending limbs and a local maximum have not been previously reported.
- Duty cycle, the proportion of the rowing stroke during the pull phase, is not fixed and affects average muscular power output.
Purpose of the Study:
- To fully describe maximal short-term rowing force-velocity and power-velocity relationships.
- To determine the apex of the power-velocity relationship.
- To assess the influence of freely chosen duty cycle on stroke power.
Main Methods:
- Collegiate male rowers (N=11) performed maximal rowing trials using an inertial load ergometer.
- Measured variables included force, power (averaged and instantaneous), handle velocity, and duty cycle for each stroke.
- Force-velocity and power-velocity relationships were analyzed using regression to determine optimal velocities.
Main Results:
- Force-velocity relationships were linear; power-velocity relationships were quadratic with distinct apexes for stroke (2.04 m/s), pull (3.25 m/s), and instantaneous power (3.43 m/s).
- Maximum power outputs were recorded for stroke (812 W), pull (1995 W), and instantaneous (3481 W).
- Freely chosen duty cycle significantly decreased from the first stroke (58%) to the fifth stroke (26%).
Conclusions:
- The study characterized maximal rowing force-velocity and power-velocity relationships, identifying optimal velocities for maximal power production.
- Differences between maximum pull and stroke power underscore the critical role of duty cycle in rowing performance.
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