Impact of Neuromuscular Electrical Stimulation Versus Plyometric Training on Muscle Power, Agility, Pain Intensity, Functional Performance, and Quadriceps Strength in Athletes with Patellofemoral Pain Syndrome

Abstract

Background: Patellofemoral Pain Syndrome (PFPS) is a prevalent musculoskeletal disorder in athletes, leading to anterior knee pain, impaired performance, and reduced functional capacity. Neuromuscular Electrical Stimulation (NMES) and plyometric training are rehabilitation strategies designed to improve muscle strength, agility, and functional outcomes, yet direct comparisons of their efficacy remain limited. Objective: This study aimed to compare the effects of NMES and plyometric training on muscle power, agility, pain intensity, functional performance, and quadriceps strength in athletes with PFPS. Methods: A randomized controlled trial was conducted with 60 athletes aged 18–30 years diagnosed with PFPS. Participants were randomly assigned to NMES or plyometric training for six weeks, three sessions per week. Outcomes included vertical jump test (muscle power), T-test (agility), Visual Analog Scale (pain), single-leg hop test (functional performance), and isometric knee extension (quadriceps strength), assessed at baseline, three weeks, and six weeks. Data were analyzed using repeated-measures ANOVA with adjustments for confounders. Results: Both groups demonstrated significant improvements across all outcomes. Plyometric training produced superior gains in muscle power (mean difference at week 6: −5.3 cm, p = 0.03) and agility (difference 0.8 s, p = 0.01), whereas NMES showed greater reductions in pain (week 6 difference −0.6 points, p = 0.50). Quadriceps strength improved similarly in both groups without significant between-group differences. Conclusion: Plyometric training is more effective for enhancing performance outcomes, while NMES offers greater analgesic benefit. Individualized rehabilitation programs incorporating both interventions may optimize recovery in PFPS athletes.