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Relationships between energetic, stroke determinants, and velocity in butterfly
T M Barbosa1, K L Keskinen, R Fernandes
1Department of Sports Sciences, Polytechnic Institute of Bragança, Campus Sta. Apolónia, Apartado 1101, 5301-856 Bragança, Portugal. barbosa@ipb.pt
International Journal of Sports Medicine
|December 2, 2005
Summary
This study found significant individual variations in the relationship between energy expenditure and biomechanics during butterfly swimming. Analyzing swimming velocity, stroke frequency, and stroke length individually is key for optimizing training intensity.
Area of Science:
- Sports Science
- Physiology
- Biomechanics
Background:
- Understanding the interplay between bioenergetic and biomechanical factors is crucial for optimizing swimming performance.
- Butterfly stroke presents unique challenges due to its complex coordination and high energy demands.
Purpose of the Study:
- To investigate the relationship between bioenergetic variables (e.g., oxygen consumption, energy expenditure) and biomechanical parameters (stroke length, stroke frequency) in butterfly stroke across various swimming velocities.
- To identify how these relationships vary among elite swimmers.
Main Methods:
- International-level swimmers performed incremental 200-m butterfly swims until exhaustion.
- Cardiopulmonary and gas exchange parameters were measured using a portable metabolic cart.
- Blood lactate concentration, stroke frequency, stroke length, swimming velocity, and stroke index were analyzed.
Main Results:
- Significant correlations were found between total energy expenditure and swimming velocity, energetic cost and stroke frequency, and energetic cost and stroke index.
- Relationships between stroke frequency and velocity, and stroke index and velocity were significant for all swimmers.
- Large inter-individual variations were observed in the relationships between bioenergetic and biomechanical variables.
Conclusions:
- Elite butterfly swimmers exhibit substantial differences in how their energy systems interact with their stroke mechanics.
- Individualized analysis of swimming velocity, stroke frequency, and stroke length is recommended to pinpoint optimal training intensities for improving energetic cost.
- Identifying the 'deflection point' in stroke length relative to velocity can inform targeted training strategies.
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