Endurance improvement of chronically exercised mice.

<p><b>A,</b> After familiarization, mice were trained for 6 weeks and sacrificed 3 days after the last bout of exercise. This cohort (“chronic exercise”) was compared to a group of mice that performed one exercise trial (“acute exercise”) and sedentary controls. <b>B,</b> An exercise protocol with incremental speed was chosen for the endurance trial and the daily training. <b>C,</b> Blood lactate measurement in mice after an acute bout of exercise (4h post exercise) and after 3 days of recovery. <b>D–G,</b> Endurance running performance of mice before (pre-exercise) and after (chronic exercise) the 6 week training: running time (panel D), distance (panel E), work (panel F) and power (panel G). Bars are average levels and error bars depict standard deviations. N = 8 animals per group pre-exercise and n = 7 animals per group for the chronic exercise (one mouse died during the training period). *p<0.05.