Abstract

This study aims to evaluate the behavior of the neuromuscular muscle groups (rectus femoris and soleus) during the execution of the squat exercise in two different protocols under varying floor angles. To quantify the muscle recruitment during exercise, surface electromyography was used with the following conditions:Free Squats, Squats with Swiss Ball support and three different floors’ positions: standard, decline (45^o of plantarflexion) and ascent (30^o of dorsiflexion). Ten healthy men were subjected to all possibilities for the exercise totaling six variations. EMG data were obtained from rectus femoris and soleus muscles bilaterally and the results of the data collection were determined by calculating the Root Mean Square (RMS). It was observed that higher values of RMS for the squat exercise on the proposed terms were obtained when the angle of the floor was at a sloping position.This result raises the possibility of choosing between the two proposed protocols, the one that is most appropriate for the patient in a specific condition, thereby generating a gain of muscle mass or strength, depending on the goals of rehabilitation.

Key words: Quadriceps, surface EMG, recruitment, squat.