Figure 6. Animal preparation and experiment design.

(a) Timeline of the study. Optical measurements and behavioral testing were performed after 5 months of voluntary exercise when the animals were 19–21 months of age. (b) Average daily running distance in km per day for each mouse in the aged exercise group, calculated as the sum of daily running distance divided by a total running period of 5 months. Data are shown as mean ± standard deviation (SD). (c) Daily running distance for two representative mice in the aged exercise group across time.