Shoulder and hip roll changes during 200-m front crawl swimming

Area of Science:

• Biomechanics of swimming
• Sports science
• Human movement analysis

Background:

• Shoulder roll (SR) and hip roll (HR) are key components of the front crawl stroke.
• Understanding roll dynamics is crucial for optimizing swimming technique and performance.

Purpose of the Study:

• To quantify shoulder roll and hip roll magnitude and changes during a 200-m maximal front crawl swim.
• To investigate the association between shoulder roll, hip roll, and swimming velocity (V).
• To analyze bilateral roll asymmetries and timing differences in shoulder and hip roll.

Main Methods:

• Ten national/international level male swimmers performed a 200-m maximal front crawl swim.
• Performance was captured using synchronized underwater and above-water cameras.
• Four non-breathing stroke cycles (SC) were analyzed for shoulder roll and hip roll calculations.

Main Results:

• Swimmers demonstrated significantly greater shoulder roll than hip roll.
• Swimming velocity generally decreased throughout the 200-m swim.
• Hip roll increased significantly from the first to the last 50m.
• Shoulder roll was negatively correlated with swimming velocity, except in the final stroke cycle.
• A significant left-side dominance in shoulder roll was observed.

Conclusions:

• Separate analysis of shoulder roll and hip roll is essential for understanding their impact on front crawl swimming.
• Faster swimmers exhibited reduced shoulder roll compared to slower swimmers.
• The observed increase in hip roll may be linked to decreased stroke frequency and increased stroke duration.
• Right-handedness may influence shoulder roll symmetry, with greater roll to the left side.