Effects of different lunges on lower limb muscle activation and patellofemoral joint loading in individuals with patellofemoral pain syndrome

Squats with lateral resistance are used in patellofemoral pain syndrome (PFPS) rehabilitation to target vastus medialis obliquus (VMO) activation, but evidence is inconsistent, and patellofemoral joint loading in these variations remains understudied. This study was to determine the differences in lower-limb muscle activation and patellofemoral joint loading during three lunge squats in PFPS individuals. Twenty-nine college athletes with PFPS performed three lunges: traditional lunge, hip-adduction lunge, and hip-abduction lunge. One-way repeated measures ANOVA was used to compare the variables of interest among the three lunges. The results demonstrated that hip-abduction lunge significantly increased the activation of the gluteus maximus and gluteus medius while concurrently reducing patellofemoral joint loading (descent phase: 2.39 ± 0.72 N/kg; ascent phase: 2.48 ± 0.61 N/kg). For PFPS individuals, the hip-adduction lunge may be more appropriate than the other two lunges when exercising the hip muscles and minimising patellofemoral joint loading.