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Predicting dive start performance from kinematic variables at water entry in (sub-)elite swimmers
Marit P van Dijk1,2, Peter J Beek1, A J Knoek van Soest1
1Department of Human Movement Sciences, Faculty of Behavioural and Movement Sciences, Amsterdam Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands.
Plos One
|October 30, 2020
Summary
Competitive swimmers
Area of Science:
- Sports Science
- Biomechanics
- Swimming Performance
Background:
- The dive start is crucial for competitive swimming, especially in short races.
- Previous studies identified key kinematic variables at water entry influencing start performance.
- The combined impact of these variables on dive start success requires further investigation.
Purpose of the Study:
- To develop a predictive model for swim start performance (time to 15m).
- To analyze the relationship between entry state variables and start performance.
- To quantify the influence of specific kinematic factors on dive start outcomes.
Main Methods:
- Fifteen elite swimmers performed dive starts with varied instructions.
- Kinematic data from video recordings were analyzed statistically.
- A mixed-effects model was used to assess entry state and start performance.
Main Results:
- Dive start performance significantly depends on the swimmer's entry state, explaining 86.1% of variance.
- Increased horizontal displacement at entry reduced start time by 0.6s.
- Higher center of mass velocity and flatter entry angle also significantly improved start times.
Conclusions:
- Swim dive start performance is predictable based on the swimmer's state at water entry.
- Optimizing horizontal velocity, entry angle, and displacement can enhance start times.
- Findings offer insights for improving dive start technique and training.
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