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Published on: January 28, 2020
Why Swimmers Go Faster: Discriminating Swimming Velocity Using Propulsive Force and Arms Coordination
Jorge E Morais1,2, Tiago M Barbosa1,2
1Department of Sport Sciences, Instituto Politécnico de Bragança, Bragança, Portugal; and.
Journal of Strength and Conditioning Research
|July 31, 2026
Summary
Swimmers achieve faster speeds by increasing propulsive force (PF) and optimizing arm coordination (IdC). Greater PF and a superposition IdC mode are key to enhancing swimming velocity.
Area of Science:
- Sports Science
- Biomechanics
- Human Movement
Background:
- Understanding the biomechanical factors influencing swimming velocity is crucial for performance enhancement.
- Previous research has explored various aspects of swimming technique, but the interplay between propulsive force and arm coordination requires further investigation.
Purpose of the Study:
- To investigate the relationship between propulsive force (PF), index of coordination (IdC), and swimming velocity in front crawl stroke.
- To determine if increased PF and specific IdC modes are associated with faster swimming paces.
Main Methods:
- 12 swimmers (9 males, 3 females) performed front crawl at 200-m and 50-m (all-out) paces.
- Propulsive force (PF) and index of coordination (IdC) were measured.
- Univariate general linear models and effect sizes (Cohen's d, eta square) were used for analysis.
Main Results:
- Swimming velocity and PF significantly increased from 200-m to 50-m pace (p < 0.001).
- The IdC shifted from a catch-up to a superposition mode between paces (p < 0.001).
- Both PF (η2 = 0.35) and IdC (η2 = 0.18) were significant predictors of swimming velocity.
Conclusions:
- Higher propulsive force (PF) and a superposition IdC are critical for achieving maximal swimming velocity.
- Coaches can leverage these findings to improve training strategies by focusing on increasing PF, which naturally promotes a more coordinated arm action for faster swimming.
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