Treadmill versus walkway locomotion in humans: an EMG study

Abstract
A descriptive comparative study was done to validate the use of the treadmill as an experimental device to investigate the electromyographic (EMG) signal during human locomotion. Eight subjects walked on a walkway and on a treadmill and EMG recordings of several consecutive strides were made during each procedure. These recordings were made from the soleus, rectus femoris, biceps femoris, vastus medialis and tibialis anterior muscles. By using the correlation coefficient and the value of the slope of the regression line resulting from correlating the linear envelopes (digitized at 50 Hz) of EMG activity from the two walk modes, it was shown that similar profiles of EMG activity exist between the walkway and treadmill. This was so for most muscles investigated with one exception, the biceps femoris. Furthermore, there was a tendency for the treadmill data to indicate slightly larger EMG amplitudes, but lower variation, than did the walkway data. However, in view of the overall similarity of the profiles obtained from both conditions, it is concluded that the treadmill is a valid laboratory instrument to study gait.