Electromyography
EMG recordings were obtained from 5 lower extremity muscles of the kicking leg. Ag/AgCl electrodes (pickup area 5x5 mm) were placed on the middle of the muscle belly 2 cm apart (bipolar recording) on the following 4 muscles: m. gluteus maximus, m. vastus lateralis, m. rectus femoris and the m. biceps femoris caput longum. Before mounting the electrodes the skin was shaved and cleaned.