Fig. 2. Serial changes in heart rate. Data are presented as mean and SD. There was a significant treatment × time interaction ( P < 0.001). Analysis of between-groups factors for all time levels showed that heart rate was significant greater in group 1 versus group 0 at 4 min ( P =0.013), 5 min ( P =0.026), 9 min ( P =0.04), 10 min ( P =0.003), 11 min ( P =0.04), and 12 min ( P =0.001). Baseline values were not significantly different ( P =0.06).