Cannabis Receptors and the Runner’s High

[First published August 4 2010]Maybe it isn't endorphins after all.What do long-distance running and marijuana smoking have in common? Quite possibly, more than you’d think. A growing body of research suggests that the runner’s high and the cannabis high are more similar than previously imagined. The nature of the runner’s high is inconsistent and ephemeral, involving several key neurotransmitters and hormones, and therefore difficult to measure. Much of the evidence comes in the form of animal models. Endocannabinoids—the body’s internal cannabis—“seem to contribute to the motivational aspects of voluntary running in rodents.” Knockout mice lacking the cannabinioid CB1 receptor, it turns out, spend less time wheel running than normal mice.  A Canadian neuroscientist who blogs as NeuroKuz suggests that “a reduction in CB1 levels could lead to less binding of endocannabinoids to receptors in brain circuits that drive motivation to exercise.” NeuroKuz speculates on why this might be the case. Physical activity and obtaining rewards are clearly linked. The fittest and fleetest obtain the most food. “A possible explanation for the runner’s high, or ‘second wind,’ a feeling of intense euphoria associated with going on a long run, is that our brains are stuck thinking that lots of exercise should be accompanied by a reward.” In 2004, the British Journal of Sports Medicine ran a research review, “Endocannabinoids and exercise,” wh...
Source: Addiction Inbox - Category: Addiction Authors: Source Type: blogs