Activity Lomb-Scargle periodograms for B-SAP rats (A, C, E, G) and Lep-SAP rats (B, D, F, H) during light:dark (LD; A and B), dark:dark with ad libitum food (DD: C and D), and DD with restricted feeding (FR; E and F), and DD2 with ad libitum food (G and H). The dotted line represents statistical significance (P < 0.05). The robustness (or consistency) of the rhythm across time is indicated by the amplitude of the periodogram.