Your brain’s reward system activates during sustained exercise, releasing a complex blend of neurotransmitters and endocannabinoids that create the euphoric “runner’s high.” This sensation emerges from dopamine’s pleasure signals, endorphins’ pain relief, and mood-enhancing endocannabinoids that peak around 30 minutes into moderate activity. This biochemical cascade evolved to help our ancestors during persistence hunting, and today it reinforces positive exercise habits. Understanding these mechanisms can help you optimize your workout’s mental benefits.