Figure 2.

Barcharts of changes in heart rate at baseline, during caloric restriction, and free feeding. Mean sleeping heart rate (A) and the sleeping-to-waking heart rate increment (B) were measured every night in all 12 participants at baseline, during caloric restriction and free feeding. Vertical bars represent the standard error of the mean. Measurements were compared using analysis of variance (ANOVA) with repeated measures to test for within-subject changes. The within-subjects P value was adjusted using the Greenhouse-Geisser correction factor for lack of sphericity. Pairwise comparisons of the three study phases were performed by two-sided Student t-test when appropriate. A P value of 0.05 was considered significant after Bonferroni correction for multiple comparisons.