Figure 7. Age-related impairments in keto-adaptation are ameliorated with TRF and a previous keto-adaptation cycle. (A) Timeline of dietary interventions used for groups (A, B). Solid blocks indicate TRF-KD, empty blocks indicate TRF-SD. (B) GKI during 1 week of keto-adaptation is significantly lower in TRF-KD-fed rats that transitioned from TRF (red) relative to ad libitum-fed animals (black). However, rats that transitioned from TRF-SD to TRF-KD with a previous cycle of TRF-KD (blue) showed the lowest GKI. (C) Consumption of the TRF-SD was associated with high baseline GKI levels immediately after the cessation of carbohydrate restriction. Data are represented as group mean ± 1 SEM, * indicates p < 0.05 for individual time points, whereas # indicates significant difference across cycles, irrespective of day. For all panels n = 10 young, n = 8 aged.