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05:12
Swimming Performance Assessment in Fishes
Published on: May 20, 2011
Relationships between glide efficiency and swimmers' size and shape characteristics
Roozbeh Naemi1, Stelios G Psycharakis, Carla McCabe
1Faculty of Health, Staffordshire University, Stoke-on-Trent, UK.
Journal of Applied Biomechanics
|November 17, 2011
Summary
Swimmer glide efficiency improves with decreased velocity. Body shape, particularly the chest-to-waist taper and upper body fineness ratio, significantly influences glide performance more than body size.
Area of Science:
- Sports Science
- Biomechanics
- Human Physiology
Background:
- Glide efficiency is crucial for minimizing deceleration in swimming. Body size and shape are known factors influencing hydrodynamic performance.
- Understanding these factors can optimize swimming technique and training.
Purpose of the Study:
- To investigate the relationship between glide efficiency and morphological (size and shape) characteristics in swimmers.
- To identify specific body shape indices that correlate with improved glide efficiency.
Main Methods:
- Eight male and eight female swimmers performed horizontal glides at a controlled depth.
- Photogrammetry was used to measure morphological indices.
- Glide efficiency was calculated at specific velocities and Reynolds numbers; correlations and ANOVA were used for analysis.
Main Results:
- Glide efficiency increased as velocity decreased for all swimmers.
- Several morphological indices and postural angles significantly correlated with glide efficiency.
- The glide coefficient showed significant correlations with chest-to-waist taper, upper body fineness ratio, and chest-to-hip cross-section (males), and waist-to-hip taper (females).
Conclusions:
- Swimmer glide efficiency is more influenced by body shape characteristics and postural alignment than by overall size.
- Specific indices like chest-to-waist taper are key predictors of glide performance.
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