‍Purpose:  

To examine the effect of a 10-week flywheel resistance training (FRT) program on kinetic parameters during change of direction (COD) in U-19 soccer players. 

Methods: 

34 professional Spanish soccer players were divided into a FRT group (n = 17) or control group (CON, n = 17).  Both groups were involved in their normal on-field soccer training (practices and matches).  The FRT group participated in 1 – 2 weight training sessions per week for 10 weeks with two exercises per session (flywheel squat and flywheel leg curls).   The starting volume for each exercise occurred at 3 sets of 6 reps during the first week and linearly progressed up to 6 sets of 6 reps in week 10.  Load was determined via inertial load power profile, in which they assessed which inertial load achieved the highest concentric power output for each individual across multiple loads (i.e., the optimal power load).  A host of kinetic parameters were measured via force plates during 2 different COD assessments before and after the training intervention.  

Results: 

The flywheel group was able to produce significantly greater braking and propulsive forces and impulses, and a lower braking and propulsive contact time.  More specifically, they saw improvements up to 32% in braking and 26% in propulsive forces, 23% in braking time, 18% in contact time, and 15% in impulse.  

Key Takeaways: 

• Utilizing an inertial power profile assessment to individualize inertial load to an athlete’s power capabilities seems to be an effective way to program and improve performance.  

• Implementing flywheel training 1 – 2 times a week can dramatically improve athletes COD and deacceleration abilities.