Electromyographic activity characteristics of quadriceps setting in different training positions

Abstract

Purpose：Although there have been several reports comparing the amount of Electromyographic （EMG） activity in the quadriceps setting in different positions in the past, the recommended training position differs depending on the reporter. In this study, we compared EMG activities of the vastus medialis muscle （VM）, vastus lateralis muscle （VL）, and rectus femoris muscles （RF） in 5 quadriceps setting positions that have been shown to be effective, and reexamined which training method is best. Methods：The following five EMG activity levels were measured 2 times isometric contractions of Maximum Voluntary Contraction on the dominant leg for 5 seconds each. （1） Straight Leg Raise exercise （SLR） with the lower leg fixation at the ankle joint in the supine position（ Fixation SLR SET）.（ 2） Quadriceps Setting exercise in which the subject presses the heel against a target in a long sitting position（ Heel SET）.（ 3） Quadriceps Setting exercise in the prone position keeping the toes on the floor（ Prone SET）.（ 4） Quadriceps Setting exercise with synchronized hip adduction in the standing position with foot in inversion （Standing Synchronized SET）. （5） Knee joint extension exercise with knee joint flexion fixed at 60° in sitting position（ Sitting Knee ext SET）. Results: In VM, Heel SET was significantly higher EMG activity than Standing Synchronized SET exercise; in VL, Fixation SLR SET, Heel SET, and Prone SET were significantly higher than in the Standing Synchronized SET exercise; in RF, Fixation SLR SET and Sitting Knee ext SET were significantly higher than in the Standing Synchronized SET exercise. Conclusion: The effective positions for each of VM, VL, and RF were different, and we recommend training methods for each muscle based on the results of this study.