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Developing a methodology for estimating the drag in front-crawl swimming at various velocities
Kenzo Narita1, Motomu Nakashima2, Hideki Takagi3
1Doctoral Program in Physical Education, Health and Sport Sciences, University of Tsukuba, Japan.
Journal of Biomechanics
|March 3, 2017
Summary
A new method using measured residual thrust (MRT) accurately estimates active drag (Da) in swimming. This active drag was found to be greater than passive drag (Dp), offering valuable data for swimming analysis.
Area of Science:
- Sports Science
- Biomechanics
- Fluid Dynamics
Background:
- Evaluating drag in swimming is crucial for performance analysis.
- Existing methods may not capture drag across various swimming velocities and full strokes accurately.
Purpose of the Study:
- To develop and introduce a novel method for assessing swimming drag.
- To estimate active drag (Da) using measured residual thrust (MRT) at different velocities.
- To compare active drag with passive drag (Dp) in front-crawl swimmers.
Main Methods:
- Introduced the principle and apparatus for the measured residual thrust (MRT) method.
- Estimated active drag (Da) for velocities from 1.0 to 1.4 m/s.
- Measured passive drag (Dp) for velocities from 0.9 to 1.5 m/s.
Main Results:
- Active drag (Da = 32.3 v^3.3) was significantly larger than passive drag (Dp = 23.5 v^2.0).
- Variability in active drag measurements for two swimmers was low (6.5% and 3.0%).
- The MRT method demonstrated reliability and applicability across different swimming velocities.
Conclusions:
- The MRT method provides a viable approach for evaluating active drag in swimming.
- Findings highlight the difference between active and passive drag, important for training and technique.
- This method has the potential for broad application across various swimming styles and research.
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