‍Purpose 

The gravity-independent resistance and enhanced eccentric loading offered by flywheel training may make it particularly useful for developing strength and function in commonly injured areas of the upper extremity, such as the shoulder. This study evaluated whether adding flywheel exercises to a shoulder training program improved shoulder strength and function measures in youth tennis players.  

Methods 

26 competitive youth tennis players were assigned to either a flywheel training group or a control group. Both groups completed 3 sessions per week for 12 weeks, which included regular tennis training, stretching, and shoulder exercises with elastic tubing resistance. The flywheel group also performed 10-15 minutes of flywheel exercises during each session. Measures of shoulder muscle strength, range of motion, and asymmetry were measured before and after the training intervention.  

Results 

The flywheel group had several significant improvements, including: 

• Increases in shoulder internal rotation (IR) strength on the dominant (+3.3%) and non-dominant (+6.3%).  

• Increases in shoulder external rotation (ER) strength on the dominant (+21.4%) side.  

• Improved shoulder IR range of motion on the dominant (+15.2%) and non-dominant (+2.6%) side and reduced glenohumeral internal rotation deficit (36.2%).  

The control group did not have significant changes in any measure.   

Key Takeaways 

The addition of 10-15 minutes of flywheel exercises to the routine resulted in significant improvements in shoulder ER and IR strength, and shoulder IR range of motion, which were not observed when only performing stretching and elastic tube resistance exercises. This indicates that flywheel training could be a simple and efficient way of improving measures of shoulder function which are considered important for both performance and injury risk.