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Breaststroke and butterfly intercycle kinematic variation according to different competitive levels with Statistical
Aléxia Fernandes1, Mário J Costa1, Bruno Mezêncio2
1Centre of Research, Education, Innovation and Intervention in Sport and Porto Biomechanics Laboratory, Faculty of Sport, University of Porto, Porto, Portugal.
Journal of Biomechanics
|October 25, 2024
Summary
Elite swimmers exhibit superior sprint breaststroke and butterfly techniques, showing distinct kinematic variations. While breaststroke consistency is maintained, butterfly shows velocity decay, highlighting skill-level differences in swimming mechanics.
Area of Science:
- Biomechanics
- Sports Science
- Motor Control
Background:
- Breaststroke and butterfly require advanced motor skills for efficient propulsion.
- Understanding intercycle kinematic variation is crucial for differentiating swimmer expertise.
- Coordinated force interaction is key to swimming performance.
Purpose of the Study:
- To analyze intercycle kinematic variations in breaststroke and butterfly sprints between elite and national level swimmers.
- To identify differences in swimming technique and performance metrics based on skill level.
- To investigate the relationship between kinematic patterns and sprint performance in competitive swimmers.
Main Methods:
- Twenty elite and 15 national level swimmers performed 25m sprints in breaststroke and butterfly.
- Underwater cameras (120 Hz) captured sagittal plane kinematics.
- Analysis included mean/max/min velocities, stroke rate/length, intracycle variation, and phase durations; statistical parametric mapping was used for intergroup comparisons.
Main Results:
- Elite swimmers demonstrated significantly higher mean and maximum velocities in breaststroke.
- Elite swimmers showed superior mean, maximum, and minimum velocities, and stroke rate in butterfly compared to national level swimmers.
- While breaststroke showed consistent intercycle kinematics across skill levels, butterfly exhibited a mean velocity decay, with variability linked to upper limb recovery and outsweep phases.
Conclusions:
- Skill level significantly impacts technical and strategic execution in sprint breaststroke and butterfly.
- Elite swimmers possess more refined kinematic profiles, particularly in butterfly propulsion.
- Despite performance differences, both elite and national level swimmers display comparable velocity variability between consecutive swimming cycles.
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