I'll also note that the human body produces its own molecules that bind to cannabinoid receptors. Physical exercise is one of the triggers for the body to do t

I'll also note that the human body produces its own molecules that bind to cannabinoid receptors. Physical exercise is one of the triggers for the body to do this. It's thus not surprising that some of the benefits of exercise on the brain are seen when cannabinoids are ingested. See e.g. https://en.wikipedia.org/wiki/Endocannabinoid_system https://en.wikipedia.org/wiki/Endocannabinoid_system