Effect of hip positions on electromyographic activity of vastus medial oblique (VMO) and vastus lateralis (VL) during prone plank exercises

Abstract

Introduction Prone plank exercises improve overall core stability. However, decreased corestability may cause knee injury, specifically anterior knee pain – for example, anterior cruciateligament injury, resulting in knee injuries caused by hip muscles, and general knee muscle weakness [especially vastus medialis oblique (VMO) and vastus lateralis (VL)].
Materials and Methods A cross-sectional study was performed with 20 healthy volunteers carrying out prone plank exercises, using surface electromyography to measure the subject’s VMO and VL during hip adduction, hip abduction as well as with the hip in neutral position.
Results Prone plank exercises with different hip positions did not generate statistically significant differences in VMO : VL ratios for both of the subject’s legs while in different hip positions (p < 0.05). As well, VMO : VL ratios of both legs in all groups was not statistically different from 1.0 (p < 0.05).
Conclusions Prone plank exercises could promote muscle activation of VML : VO for both of the subject’s legs.