Saturday, June 21, 2008
Battling Addiction with Exercise
It helps you quit. Can it keep you from starting?
We've all heard the claim: Physical exercise helps addicts who are working their way through withdrawal and recovery. It is one of the most common prescriptions given out by doctors and health professionals, whether you are a recovering alcoholic or a chronic binge eater.
And it makes sense. Exercise has verifiable impacts on not just endorphin levels, but also on levels of circulating serotonin and dopamine. All three neurotransmitter systems are heavily implicated in both maintaining addiction and withdrawing from it. Countless drug addicts have extolled the virtues of vigorous exercise, and there seem to be no compelling reason to doubt them.
But is there reason to think that regular exercise can help prevent addiction from blossoming in the first place?
Dr. Nora Volkow, director of the National Institute on Drug Abuse (NIDA), thinks there is. She told the Cincinnati Enquirer: "It's something we could apply right away. Vaccines, we're not going to get those results in one or two years. It will take probably five, six years to results."
"Exercise has been shown to be beneficial in so many areas of physical and mental health," Volkow said recently at a NIDA-sponsored conference on addiction treatment and research in Cincinnati. "This cross-disciplinary meeting is designed to get scientists thinking creatively about its potential role in substance abuse prevention."
Dr. Bess Marcus of Brown University, who is working on a NIDA-funded study of exercise for smoking cessation, presented the scientific evidence for the addiction/exercise connection. Similarities in the effects on the reward pathways of the brain's limbic system--dopamine activity in particular--may tie the two behaviors together more directly than previously thought. Among the findings:
--Rats in cages with running wheels show less interest in amphetamine infusions than rats without exercise options.
--Baby monkeys who don't roughhouse with their peers have higher levels of impulse control problems and alcohol use when they get older.
--In humans, exercise is known to reduce stress and tension--and anxiety is a well-known side effect of withdrawal, from alcohol and cigarettes to heroin and speed.
--Physical activity may enhance cellular growth in key areas of the brain involved in addiction, thereby aiding the neural rewiring that takes place during detoxification and withdrawal from addictive drugs.
No one knows for sure whether this effect, if it exists, works only in the young, and declines with age, or whether it can be of benefit to anyone as a preventative measure to reduce drug craving. "Statistics indicate that teens who exercise daily are the least likely to report using drugs or alcohol," Volkow said.
However, there are numerous exceptions, one being the classic image of the hard-drinking athlete. "Now the kids who exercise the most actually drink the most," Dr. Lloyd Johnston of the University of Michigan told the Associated Press.