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A Rapidly Incremented Tethered-Swimming Maximal Protocol for Cardiorespiratory Assessment of Swimmers
Published on: January 28, 2020
Rolling rhythms in front crawl swimming with six-beat kick
Ross H Sanders1, Stelios G Psycharakis
1Centre for Aquatics Research and Education, PESLS, The University of Edinburgh, St Leonard's Land, Holyrood Road, Edinburgh, Scotland 8AQ, UK. r.sanders@ed.ac.uk
Journal of Biomechanics
|January 2, 2009
Summary
This study analyzed the rhythm of elite front crawl swimmers using a six-beat kick. Findings reveal consistent shoulder movement and a body wave from hip to ankle, indicating efficient aquatic locomotion.
Area of Science:
- Biomechanics of swimming
- Fluid dynamics in aquatic sports
Background:
- Front crawl is a dominant swimming stroke.
- Understanding the six-beat kick is crucial for optimizing propulsion and efficiency.
Purpose of the Study:
- To characterize the rhythm of skilled front crawl swimmers employing a six-beat kick.
- To analyze the power contributions of Fourier harmonics in body segment angular displacements.
Main Methods:
- Collected 3D video data from seven elite swimmers during simulated 200m front crawl races.
- Analyzed angular displacement signals of shoulders, hips, knees, and ankles using Fourier harmonics (H1, H2, H3).
- Assessed variability across four 50m laps and changes during the 200m race.
Main Results:
- Shoulder roll remained constant, dominated by the first harmonic (H1).
- Significant changes across laps were observed in swimming speed, stroke rate, hip roll, and H3 wave velocity.
- A third harmonic (H3) body wave traveled from hip to ankle with increasing velocity.
Conclusions:
- The observed rhythm characteristics, particularly the H3 body wave, are consistent with efficient propulsive mechanisms in front crawl swimming.
- Elite swimmers exhibit consistent shoulder kinematics but dynamic changes in lower body wave propagation during a 200m race.
- These findings contribute to a deeper understanding of aquatic locomotion and stroke optimization.
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