Muscle activity during bridge exercises on different types of floor surfaces

Bridge exercises help strengthen the muscles of the lower limbs and trunk. Previous studies have examined muscle activity during bridge exercises using balance balls and balance mats during which the body’s balance is only partially disturbed. However, no study has examined muscle activity during bridge exercises when performed on an air mattress, during which the entire body is not balanced. Therefore, the purpose of this study was to verify the differences in muscle activity during bridge exercises when performed on a hard surface like a platform or on an air mattress. Twenty-four healthy university students were instructed to perform bridge exercises using three different knee joint angles (90°, 110°, 130°) and two different types of floor surfaces. Muscle activity of the erector spinae, gluteus maximus and lateral hamstrings was measured by using a surface electromyograph, Each muscle showed significantly higher levels of muscle activity during certain knee joint angle conditions when performed on an air mat (p < 0.05). In the erector spinae, muscle activity at 90° was significantly higher than at 130° of the knee joint in the air mattress condition. For the gluteus maximus, there were no significant differences among the angles of the knee joint. The results of this study show that muscle activity while performing bridge exercises increases when the entire body is placed on a soft surface.