Fig. 6. Bar chart of - and ß-burst intensities from the lateral hypaxial muscles of one tiger salamander (individual A) during walking and swimming. For this individual, the intensity of the -bursts is significantly higher than the intensity of the ß-bursts in all four lateral hypaxial muscles during both swimming and walking (paired t-test, P<0.0001). The muscle burst intensity was measured as the rectified integrated area divided by the duration of the burst. Filled and open columns represent the mean burst intensity + S.E.M. of the - and ß-bursts, respectively.