A BIOMECHANICAL STUDY OF DYNAMICS AND EMG IN GYMNASTICS: BACKWARD ROLL TO HANDSTAND

Abstract

In this paper, a dynamical and eletromyographical (EMG) analysis were applied to study a gymnastics movement, the backward roll to handstand. In order to improve and combine technical knowledge and biomechanical description and analysis of sport movements, dynamical approaches have been developed in this sense. Two trained subjects performed this movement. In the EMG analysis, bi-polar surface electrodes were used on the motor point of right m.gluteus maximus and m.triceps suralis and full wave rectification of signal stook place. In the Dynamical analysis, a strain gauges force plate was used to collect the signals of vertical and horizontal ground reaction force (GRF) during the backward roll, and the impulse to handstand. An A/D convertor that simultaneously interfaced the two signals to a computer was employed. The frequency rate for both procedures was 750 Hz. The description of the vertical GRF showed two different peaks during the execution of the backward roll until handstand. These two peaks are related to the extension of hip and lower limb, and the extension of the elbow and flexion of the shoulder. The EMG signals demonstrated a different time duration of muscular activation. In fact, postural corrections of body position during the movement may maintain a high muscular activation. A performance evaluation of sport movements is important to improve technical knowledge and to provide accurate biomechanical methodologies to permit the description, analysis and evaluation of sport movements.