Reviewed by Thomas Watson, RRCA-certified running coach & Marathon Handbook founder. Key Takeaways Yes, the runners high is real and well-documented. Modern neuroscience shows it is driven primarily by endocannabinoids (not endorphins as long believed), plus increased blood flow to mood centers and reduced anxiety. Most runners experience it after 20-40 minutes of moderate-intensity running. … Continue reading Is Runner’s High Real? What It Feels Like + How Long It Lasts