(Reverse) Morris water maze. Spatial learning and memory were assessed in the Morris water maze (MWM) at baseline (chow) and in a reverse MWM 5 months after allocation in treatment groups (HFD, HFD + exercise, HFD + BCAA + exercise). (A) During 4 constitutive acquisition days, chow-fed mice learned to find the hidden platform. After 5 treatment months, animals of all treatment groups were again subjected to an acquisition trial (2 days) with a novel platform location. The latency to find the hidden platform is indicative of spatial learning ability. (B) Total swim distance was measured during both acquisition phases (baseline and reverse). (C–F) In the probe trial of the reverse MWM, the platform was removed from the pool, and (C) the time spent at the former platform location, (D) frequency of crossing the former platform location, (E) time spent in the former platform quadrant, and (F) the frequency of crossing the former platform quadrant were measured. High-fat diet (HFD), branched-chain amino acids (BCAA). Data are presented as mean ± SEM. * p < 0.05, ** p < 0.01, # 0.05 < p < 0.08 (trend); b: difference HFD vs. HFD + BCAA + exercise group.