Science in Action: Exercise (confirmation)

During my omega-3 tests, I noticed that exercise seemed to be reducing reaction time (= better brain function). When I tested this, the results surprised me: Reaction time wasn’t lower immediately after exercise but became lower later. Did exercise have a delayed effect or was the shower I took soon after exercise responsible?

To find out, I did a little experiment. The earlier exercise was 30 minutes on a flat treadmill at about 2.8 miles/hour; this time I walked 30 minutes on a steep treadmill at higher speed (about 3.7 miles per hour). Here are the results:

Vertical lines show when the exercise started and stopped. This time there was improvement immediately after the exercise (unsurprising, given that it was much more intense) but even more improvement a half-hour later. I took a shower several hours later; it had no clear effect. The improvement lasted several hours before starting to diminish.

The data are very clear. They imply the earlier results can be believed: Exercise does improve brain function in an unanticipated way. Losing weight with exercise is hard; improving brain function with exercise appears easy. I want to study this effect in detail. Not only should it teach me how to improve brain function, it should also suggest the best dose of exercise for the rest of my body.