EMG MEDIAN POWER FREQUENCY IN AN EXHAUSTING EXERCISE

EMG median power frequency of the calf muscles was investigated during an exhausting treadmill exercise. This exercise was an uphill run, th e average endurance time was 1.5 min. Median power frequency of the ca lf muscles declined by more than 10% during this exercise. In addition EMG median power frequency of isometric contractions of the same musc les was measured before and in one minute intervals for 10 min after t his run. Immediately after the run isometric median power frequency ha d declined by less than 5% for the soleus muscle, more than 10% for th e gastrocnemius medialis and gastrocnemius lateralis muscles. In the 1 0 min following exercise the isometric median power frequency increase d to pre-exercise levels. Maybe the median power frequency shift to lo wer frequencies during dynamic exercise can be interpreted as a sign o f local muscle fatigue.