Remember what I said about feeling high?

From a Runner's World, June 2004, article by Amby Burfoot "Is there really a runner's high?"

From his readings in the field, Dietrich knew about a relatively new brain receptor site, first discovered in 1990. This site was shown to be the receptor for THC, the active ingredient in marijuana that produces another kind of high entirely. The site was named the cannabinoid receptor.

since the body is an intelligent system that doesn't develop receptors for no reason at all, this meant the new receptor must be home to a natural body chemical--and not just THC, an exogenous, or "outside the body" substance. The natural chemical was discovered in 1992. It's called anandamide, from the Sanskrit word for "bliss." Anandamide is very similar to THC, and it produces pleasant feelings of relaxation and pain cessation similar to those often described by runners and pot smokers.

Could anandamide be the missing link to runner's high, the substance that endorphins were not? On one long run, Dietrich worked out all the details. "I was convinced that I had hit the nail on the head when it came to a biological explanation for runner's high," he says. "Of course, it would take me two years to prove it."

He started by devising a simple experiment with a small group of subjects who ran or bicycled for 40 minutes and 76 percent of their max heart rate, and then had blood samples drawn immediately after exercising. next the blood samples were flown to a special lab in Irvine, California. The results showed that both the runners and bicyclists had significantly more anandamide in their blood after exercising, with the greatest increase among the runners.

Equally important, as Dietrich already knew, anandamide doesn't have a blood-brain barrier problem, the way endorphins do. if you've got anandamide in your blood, it's going to reach your brain, where the cannabinoid receptor will hungrily grab it and give you a nice buzz. "Anandamide is a tiny little fatty acid that crosses the blood-brain barrier like nobody's business," says Dietrich.

Anandamide does more than just get you high. It also dilates your blood vessels and the bronchial tubes in your lungs. both of these physical adaptations should help you run better and longer.

This makes perfect sense to Dietrich.

Not to mention myself. This is an article that first explained why endorphins can not be the cause of this so-called "runner's high." But now, we know the truth! :)