When people think about addiction, drugs, alcohol or such impulsive activities as gambling often come to mind. Illicit drugs are commonly considered to be risky in any quantity, while substances like alcohol and prescription drugs are not necessarily inherently dangerous, but can be harmful if used incorrectly or to excess. Gambling can be regarded in a similar light - it does not become a problem for everyone, but some people have lost everything they own as a result of their addiction. But what if someone were addicted to an activity or substance that is generally considered to be beneficial? Is such a situation even possible, and, if so, would such an addiction be considered a problem? Exercise is a great activity to examine in this light. Exercise is a tremendously important element of good overall health, both physical and mental. Furthermore, maintaining the willpower to exercise on a regular basis is very challenging for many people. Although exercise generates rewarding endorphins, it also involves exertion that many people find difficult, and even unpleasant or painful. As a result, the idea that a person could develop an addiction to exercise might seem appealing and beneficial. Is Exercise Addiction Possible? The only behavioral addiction that is currently recognized by the Diagnostic and Statistical Manual of Mental Disorders (DSM) is gambling. Nevertheless, research onto various other kinds of behavioral addictions has multiplied in the years since the most recent manual - the DSM IV - was published. Much of this research suggests that people can indeed develop addictions to certain behaviors that result in a re-programming of their brains' feedback and reward centers. Research into exercise addiction has found that rats in a laboratory setting can become addicted to running on a wheel. Other research into human subjects has found that exercise releases chemicals into the brain that are strongly associated with addiction, such as endorphins, endocannabinoids, and enkephalins. Exercise also seems capable of creating feedback patterns in the brain that cause increased tolerance and cravings. It may be some time before the scientific evidence is sufficiently overwhelming and consistent for the conservative DSM to include exercise addiction in its pages. However, current research and anecdotal evidence suggests that it can be a genuine addiction. Is Exercise Addiction a Problem? So, if exercise addiction is indeed possible, is such an addiction necessarily a bad thing? Is it ever a bad thing? Or can it promote overall health to develop an addiction to an activity that is beneficial to our health? The reality is that a true addiction is always going to negatively impact a person's life in some way, particularly as it develops. An addiction should not be confused with a habit, which can indeed be a beneficial influence on a person's mind. While both are characterized by repetitive behavior patterns, an addiction is a habit of which a person is no longer in control, and which has taken over their life to a disrupting degree. One serious feature of addiction is that it requires ever-increasing exposure to the behavior or substance in question in order for the addict to be satisfied. Although regular exercise is healthy, some exercise addicts report the need to exercise four or five hours per day, or even more. As a person's tolerance increases, he or she is forced to devote an increasing amount of each day to exercise in order to produce the same feeling. Furthermore, addicts are not in control of their need to acquire a substance or engage in certain behavior. While habits may lead people to engage in certain activities without thinking, they do not compel them toward those activities if they choose not to. However, a true addiction gives the addictive activity or substance an artificial importance that eventually outweighs everything else in a person's life. For a person addicted to exercise, the ability to perform those exercises may be valued over work, school, friends, family, and other important parts of life. So while the short term benefits of an addiction to exercise - or a similar activity with generally positive associations - may be present, the long-term effect of an addiction is always going to be a loss of control and the amplification of behaviors to a dangerous extent. Furthermore, interruptions in the ability of addicts to satisfy their cravings put them at greater risk for impulsive and potentially risky behaviors to help them assuage their need for reward stimuli.