Fig. 9. Mean rectified integrated area of the of activity of the longissimus dorsi muscle in the two loaded conditions plotted as a percentage of the mean value in the unloaded condition (= 100% EMG intensity). In three of the dogs the mean EMG activity from the girdles-loaded condition was not significantly different from the unloaded condition. In one of the dogs the mean EMG energy from the girdles-loaded condition was significantly lower than the mean EMG energy from the loaded condition. In all four dogs the mean EMG activity from the mid-trunk loading condition was significantly greater than both the unloaded condition and the girdles-loaded condition.
