Abstract
We designed a 6-min motor stress test on bicycle ergometer at three different exercise intensities of 50, 100 and 150 W, and examined the relation between muscle fatigue of vastus lateralis muscle and the exercise intensity from the results of integrated EMG (IEMG) and median power frequency (MdPF) of 8 healthy males. At the exercise intensities of 50 and 100 W, there was no change both in IEMG and MdPF throughout the experimental period. At the exercise intensity of 150 W, there was no change in IEMG and MdPF until 3 min, but an increase in IEMG and a transfer of MdPF to the low frequency range were observed in 5 subjects from 4 min. This suggests that muscle fatigue of vastus lateralis muscle is induced at the exercise intensity from 100 to 150 W.
