This is a question is being addressed by the University of Texas Southwestern Medical Center in collaboration with National Institute on Drug Abuse (NIDA), in a study with people in residential treatment for addiction to stimulants such as cocaine, methamphetamine, amphetamine, or other stimulants, but excluding caffeine and nicotine.
While the mental and physical health benefits of exercise have long been recognized, whether it can actually prevent addiction remains to be seen. In 2008, more than 100 scientists from around the United States gathered for a two-day conference exploring importance of the social context in which physical activity occurs, including school and the natural environment, as well as the relationship of physical activity to physical disorders (obesity), social reward structures (motivation), cognition (attention, impulse control and other motor skills), and mood disorders
(depression, stress), all of which may play a role in substance abuse. Since then, there has been significant interest -- and funding -- into exploring ways that exercise can be used to prevent and treat addiction.
This is an exciting area for research to be heading, particularly as exercise is a natural and healthy way to tackle many of the struggles associated with overcoming addiction. However, while I always encourage moderate exercise, it should be remembered that exercise can be addictive. People with an addictive personality are at particularly high risk of a crossover addiction to exercise being masked, because it is seen as such a healthy behavior.