Circadian rhythm of behavioral activity, core body temperature and food intake in sedentary and wheel-running mice.

<p>(A) Representative actogram in mice housed with access to running-wheels (RW) for four weeks. Light/dark cycles are shown as white/black bars, respectively. (B) Hourly distance of wheel-running by RW mice over 24 h calculated based on numbers of revolutions/h during fourth week of experiment and running-wheel diameter. Gray shading indicates dark period. Data are shown as means ± SEM (<i>n</i> = 3–4). (C) Core body temperature (Tb) rhythm for 24 h under 12 h light-12 h dark cycle. Mice were housed under sedentary (SED; red line) conditions or given free access to running-wheels (RW; blue line) for four weeks and Tb was measured during fourth week. Data are shown as means ± SEM (<i>n</i> = 4–5). Gray shading indicates dark period. (D) Circadian rhythm of food intake for 24 h under 12 h light-12 h dark cycle. Food intake was measured every 30 min during fourth week of the experiment in SED (unfilled circles) and RW (filled circles) mice. Data are shown as means ± SEM (<i>n</i> = 3–4). Gray shading indicates dark period. *<i>P</i> < 0.05 and **<i>P</i> < 0.01, significant differences between SED and RW mice at corresponding Zeitgeber times (ZT).