The Effect of Standing and Kneeling Postures on Muscle Activity for Squat

Objective: This study aimed to identify the effects of assuming two types of posture (standing and kneeling) during squat exercise on lower body muscle activity. Design: Cross-sectional study Methods: Twenty-five healthy adults (18 men and 7 women) were instructed to perform the squat exercises while assuming two types of posture (standing and kneeling). EMG (Electromyography) data (% maximum voluntary isometric contraction) were recorded three times from the rectus femoris (RF), gluteus maximus (GMax), gluteus medius (GMed) and biceps femoris (BF) of participant's dominant side and the mean values were analyzed. Results: During the squat exercise with all postures, there was statistically significant difference on rectus femoris, gluteus maximus, gluteus medius, and biceps femoris muscle activity (p<0.05). The results showed that, there was significantly greater rectus femoris, gluteus medius, and biceps femoris muscle activity in standing posture than in kneeling position (p<0.05). However, the gluteus maximus muscle activity was significantly greater with kneeling posture compared to standing posture (p<0.05). Conclusions: With standing posture, it is showed that rectus femoris, gluteus medius, and biceps femoris muscle activity was greater than kneeling position. While the gluteus maximus muscle activity with standing posture was less than with kneeling posture. Therefore, it is considered that this study can be used as a selective indicator of exercise posture for strengthening specific muscle or weakness caused by paralysis.