A single, half-hour session of moderate exercise is enough to confer an immediate mood-boosting effect, and now scientists have figured out why. In mice – and likely humans – that boost comes from the release of a hormone called adiponectin, which travels into the brain and sparks activity in a region associated with emotional regulation . The result is a lift in mood that could hang around for hours, although the duration has yet to be measured in humans. There are some pretty incredible