It’s increasingly recognized that the runner’s high, which used to be attributed to endorphins, is conferred partly by endocannabinoids in the brain. In response to the stress of exercise, the brain produces anandamide, “the bliss chemical” which provides that feeling of elation along with pain reduction and health benefits. A collaboration between researchers in Wisconsin and at Iowa State University has sought to understand this phenomenon in women suffering from depression. Exercise is known to have antidepressant properties and depression is associated with changes in our endocannabinoid system; could a blissful runner’s high help pull someone up from a depressive low? Women diagnosed with major depressive disorder were assigned to a moderate exercise routine involving only 30 minutes of cycling. This routine increased anandamide levels and decreased depressive feelings. Endocannabinoid levels are often diminished in people with depression, and restoring cannabinoid tone with exercise seems promising. Of course, exercise is an important contribution to health independent of its interaction with the endocannabinoid system. Oddly, the same elevation in endocannabinoid levels was not seen when the participants exercised for 30 minutes at whatever intensity they desired. OEA (an anandamide-like molecule involved in feeling satiated with food or alcohol) levels in the blood also increased with moderate exercise, but not with the preferred-intensity group. The blood-concentration of 2-AG actually decreased with exercise, but this may have been a spurious result, as previous studies have shown an increase of 2-AG levels after working out, and the statistical methodology in this article is prone to false results.