Table 3.

Mean ± SEM Distance run (km) per Rat per 24-h Period of Wheel Access for Experiments 1–7.

Experiment	Group	n	Week 1	Week 2	Week 3	Week 4	Week 5	Week 6
1A	RUN	9	1.16 ± 0.13	3.24 ± 0.55	5.00 ± 0.74	6.08 ± 0.88	5.68 ± 0.96	4.79 ± 0.82
1B	RUN	24	0.98 ± 0.10	2.72 ± 0.35	4.51 ± 0.44	5.72 ± 0.57	5.51 ± 0.58	4.81 ± 0.51
2	RUN	6	0.96 ± 0.06	2.65 ± 0.48	4.22 ± 1.02	5.07 ± 1.42	4.83 ± 1.49	4.96 ± 1.70
3	RUN	24	1.16 ± 0.11	2.55 ± 0.30	3.63 ± 0.42	4.60 ± 0.60	5.05 ± 0.59	4.56 ± 0.61
4	RUN	8–24	1.13 ± 0.08	3.26 ± 0.23	4.92 ± 0.49	6.31 ± 1.07	6.75 ± 0.97	4.68 ± 0.87
5	RUN	24	1.22 ± 0.10	3.03 ± 0.34	4.40 ± 0.43	5.98 ± 0.53	6.22 ± 0.59	5.10 ± 0.54
6	RUN	16	1.18 ± 0.11	3.02 ± 0.39	5.43 ± 0.78	6.43 ± 0.87	7.02 ± 1.01	5.84 ± 0.90
	RUN-I	8	1.03 ± 0.07	1.93 ± 0.30	3.18 ± 0.63	3.94 ± 0.97	3.31 ± 0.74	2.25 ± 0.61
7	RUN	20	0.82 ± 0.09	2.46 ± 0.34	3.95 ± 0.58	4.58 ± 0.76	3.94 ± 0.67	3.53 ± 0.43

A repeated measures anova revealed that there was a significant effect of time on the mean distance run over the 6 week period in each of Experiments 1–7 (P = 0.001 for each experiment). The distance run peaked in weeks 4–5. For Experiment 4, in which animals were killed after 1, 3 or 6 weeks under RUN conditions, the data reflect all available animals. Hence, n = 24 for week 1; n = 16 for weeks 2 and 3; n = 8 for weeks 4, 5 and 6. RUN-I refers to the Intermittent Run group, which had access to the running wheel for only 24 h out of each 72-h period. The values reported for this group reflect the distance run during times of wheel access only.