Figure 1.

Energy metabolism of male Sprague-Dawley rats (Charles River Laboratories) fed a LF (blue line) or HF (red line) diet. Rats were fed a LF or HF diet between 4 and 13 weeks of age. See Table 2 for experimental detail. At 13 weeks of age, rats were placed in a computer-controlled Oxymax instrument (an open circuit calorimeter; Columbus Instruments, OH) to measure 24-h O2 consumption, CO2 production, RQ and heat production (34). Values are mean ± SEM during the day (24 h) at the end of the study. There were 16 rats per diet group. Results were analyzed using a mixed effect model that fits both fixed and random effects (35, 36). The sign “*” denotes a significant effect of diet at the indicated time point. The sign “#” denotes no significant effect of diet at the indicated time point. RQ: P (diet); P (diet x time); P (time); P (time x time) and P (time x time x time) are all less than 0.001. VO2: P (diet) = 0.75; P (diet x time) = 0.12; P (time); P (time x time) and P (time x time x time) are all less than 0.001. VCO2: P (diet); P (diet x time); P (time); P (time x time) and P (time x time x time) are all less than 0.001. HP: P (diet) = 0.138; P (diet x time) = 0.018; P (time); P (time x time) and P (time x time x time) are all less than 0.001.