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Updated: Jul 4, 2026
06:09
Measuring 3D In-vivo Shoulder Kinematics using Biplanar Videoradiography
Published on: March 12, 2021
[The high level swimmer articular shoulder complex]
Summary
High-level swimming weakens the shoulder joint complex, causing instability and impingement. Swimmers exhibit muscle imbalances and laxity in anterior-inferior capsuloligamentous structures compared to sedentary individuals.
Area of Science:
- Sports Medicine
- Orthopedics
- Biomechanics
Background:
- High-level swimming places significant stress on the shoulder joint complex.
- Previous assumptions suggested swimming might weaken shoulder structures, leading to specific pathologies.
Purpose of the Study:
- To analyze the shoulder joint complex in elite swimmers.
- To investigate the hypothesis that intensive swimming leads to anterior instability, impingement, and rotator cuff muscle imbalance.
Main Methods:
- A comparative study involving 20 elite front crawl swimmers and 20 sedentary individuals.
- Evaluations included comprehensive clinical examination and isokinetic shoulder testing at 60 degrees/s.
Main Results:
- Swimmers showed an unbalanced external/internal rotation ratio (0.52) compared to controls (0.75).
- Intensive swimming resulted in shoulder asymmetry and strength differences (Right: 61.2+/-10.2 Nm vs. Left: 52.8+/-9.8 Nm).
- Clinical findings in swimmers included scapular protraction (55%), mechanical impingement (35%), and anterior-inferior capsuloligamentous laxity (67%).
Conclusions:
- Elite swimming training significantly weakens the shoulder joint complex.
- Findings support the hypothesis of increased risk for anterior instability, impingement, and muscle imbalance in high-level swimmers.
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