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Updated: May 22, 2026
11:15
Determining the Contribution of the Energy Systems During Exercise
Published on: March 20, 2012
Gross efficiency and energy expenditure in kayak ergometer exercise
B B Gomes1, L Mourão, A Massart
1University of Coimbra, Faculty of Sport Sciences and Physical Education, CIDAF, Coimbra, Portugal.
International Journal of Sports Medicine
|April 28, 2012
Summary
Elite sprint kayakers
Area of Science:
- Sports Science
- Exercise Physiology
- Biomechanics
Background:
- Sprint kayaking demands significant energy expenditure and power output.
- Understanding the physiological demands is crucial for optimizing training and performance.
Purpose of the Study:
- To investigate energy expenditure, power output, and gross efficiency in elite sprint kayakers during kayak ergometer exercise.
- To analyze gender-based differences in physiological responses and performance metrics.
- To explore the relationship between energy expenditure, power output, and the contribution of aerobic and anaerobic energy sources.
Main Methods:
- 12 elite sprint kayakers (6 males, 6 females) underwent an incremental intermittent kayak ergometer protocol.
- Measurements included oxygen consumption (VO2), blood lactate concentration, and paddling power output.
- Analysis focused on VO2max, energy expenditure, gross efficiency, and gender-specific physiological responses.
Main Results:
- A non-linear relationship was observed between power output and energy expenditure.
- Male kayakers exhibited higher VO2max, power output, and gross efficiency compared to females.
- Energy expenditure at VO2max did not differ between genders, but anaerobic energy sources significantly contributed to sprint performance.
- Gross efficiency was dependent on aerobic and anaerobic contributions at higher intensities.
Conclusions:
- Elite sprint kayaking performance relies on both aerobic and anaerobic energy systems.
- Gender differences exist in physiological responses and performance metrics, with males showing higher power output and efficiency.
- Individual variations in the energy expenditure-power output relationship suggest differing skill levels among kayakers, particularly males, at specific intensities.
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