Anyone who has ever gone on a run will be familiar with that "runner's high” feeling - that euphoric sense you get after a jog where you feel on top of the world. That post-workout good mood isn't just anecdotal: research has consistently shown that, in addition to physical health benefits, exercise boosts your mood and happiness. I breakdown why exercise is such a powerful mood-booster and how it can make you happy now and in the long-term.