Purely anecdotal: I'm in my early 30s and find a brisk run to have a huge positive effect on my mental function and general energy levels for the rest of my day

Purely anecdotal: I'm in my early 30s and find a brisk run to have a huge positive effect on my mental function and general energy levels for the rest of my day (I work in biotech and spend half my day in the lab, half behind a screen). In fact, I noticed this difference my very first (pitiful) day of running.