Impact of Plyometric Training Methods on Athletic Performance and Detraining Processes in Youth Female Soccer Players

Lower extremity strength, explosive power, dynamic balance, and functional range of motion are critical determinants of athletic performance and injury prevention in soccer (football). While plyometric training is widely used to improve these qualities, the comparative effects of bodyweight plyometric training versus externally loaded plyometric training, and the maintenance of these effects during detraining periods, remain unclear. This study aims to investigate the effects of two different plyometric training methods on athletic performance and subsequent detraining processes in young female soccer players. Participants will be randomly assigned to three groups: Bodyweight Plyometric Training Group (BW-PT), External Loading Plyometric Training Group (EL-PT, who will wear vests weighing 10% of their body weight), and Control Group (CG, who will only continue with routine soccer training). Training interventions will be conducted for 6 weeks, immediately followed by a 4-week detraining period. To comprehensively assess athletic performance, the following measurements will be taken at baseline (pre-test), immediately after the training period (post-test), and after the detraining period (maintenance test): Isokinetic muscle strength of knee extensors and flexors (peak torque and force development rate at 60°/s and 120°/s), Jumping performance (standing long jump, vertical jump height, and 15-second repeated jump test), Functional range of motion (via Functional Movement Screen - FMS), Dynamic balance (via Y-Balance Test). The primary objective is to determine which plyometric loading strategy, compared to traditional soccer training, provides superior and longer-lasting physiological and biomechanical adaptations in young female athletes.