Looking at 19 earlier trials, researchers found that a bout of exercise generally helped hopeful quitters tamp down their nicotine cravings. Whether that translates into a greater chance of quitting, though, is unclear.
"Certainly, exercise seems to have temporary benefits, and as such can be strongly recommended," said Dr Adrian A Taylor, a professor of exercise and health psychology at the University of Exeter in the UK.
Serving your distraction
For its study, published online in Addiction, Dr Taylor's team identified studies that tested the immediate effects of exercise on smokers' cigarette cravings. Smokers were randomly assigned to either exercise - most often, brisk walking or biking - or some kind of passive activity.
Overall, Dr Taylor's team found, people said they had less desire to smoke after working out than they did before.
"After exercise, smokers reported about one-third lower cravings compared with being passive," Dr Taylor said.
How exercise curbs cravings
Exactly why is not clear. But one possibility, Dr Taylor said, is that exercise serves as a distraction. Being active might also boost people's mood, so that they do not feel as great a need to feel better by smoking, Dr Taylor noted.
None of the smokers in these studies was in a quit program or using nicotine replacement products, like gums or patches. Since nicotine replacement therapy curbs cravings, Dr Taylor noted, exercise might have less of an effect for smokers who are using those products, or possibly the other medications used for smoking cessation.
Those include the prescription drugs varenicline (Chantix) and bupropion (Zyban and generics).
Still, exercise is a generally healthy habit for anyone. And, Dr Taylor pointed out, smokers often gain weight when they try to kick the habit - one reason that some people, particularly women, go back to smoking.
"So increasing (calorie) expenditure can help to reduce weight gain after quitting," Dr Taylor said. He noted, though, that more research is needed to see just how effective exercise might be in warding off post-quitting pounds.
Serious attempts needed
As for whether exercise ultimately helps smokers quit, there is little to go on. Dr Taylor said only one of the studies suggested that exercise helps boost quit rates over a year. But the problem, he noted, was that most of the studies had major limitations.
Hopefully, better evidence will become available, Dr Taylor said. He added that large, good-quality studies are underway.
And smokers need all the help they can get. According to the American Lung Association, it takes smokers an average of five to six "serious attempts" to finally quit.
The group recommends that smokers try some combination of therapies - not only nicotine replacement or medication, but behavioural counselling too.
(Reuters Health, August 2012)