The Runner's High
The runner's high is a supposed state of euphoria that runners experience during or after a run. Some report feeling a powerful rush of intense emotions, calmness, physical pleasure or happiness, all of which can have an addictive effect. The hypothesis behind the runner's high is the biochemical effect of running, the brain's release of feel-good endorphins. These chemicals are the brain's naturally occurring opiates. For years, the runner's high was considered new-age lore, but a 2008 study in "Cerebral Cortex" confirmed the link between endorphin rushes and running.
David Raichlen, an anthropologist at the University of Arizona, believes human brains have been wired to encourage engaging in running and other aerobic activities. An affinity for running helped your ancestors to chase down animals for food and avoid becoming prey themselves. At the same time, the human brain may have started releasing endorphins to encourage running, which ultimately encouraged survival. Because of this, some level of the runner's high could be in the evolutionary roots of human beings, due to natural selection.
Exercise addiction can be attributed to the runner's high. Researchers at Tufts University say exercise can be as addictive as drugs. However, it isn't necessarily addictive across the board. Some people may respond to running with addiction, while others never get past the feeling of nausea and pain they associate with intense runs.
Apart from getting an endorphin fix, people may become addicted to running because of the feedback the sport gives them, such as a lean body, feelings of well-being and compliments from other people. In extreme cases, this sort of feedback-induced addiction can lead to compulsive disorders such as exercise bulimia, in which individuals become obsessed with the rituals of exercise to burn the calories they consume. Exercise bulimia is dangerous and can lead to malnutrition, severe weight loss and depression.
Speak with your doctor before beginning a new exercise program. If you suspect you have an unhealthy addiction to exercise, seek the help of a therapist.