Researchers, whose findings appeared in the journal Addiction, combined the data from 19 previous clinical trials and found that a bout of exercise generally helped hopeful quitters reduce their nicotine cravings - though whether that translated into a greater chance of quitting was unclear.

"Certainly, exercise seems to have temporary benefits, and as such can be strongly recommended," said Adrian Taylor, a professor of exercise and health psychology at the University of Exeter in Britain, who led the study.

In the trials used for the study, smokers were randomly assigned to either exercise - most often, brisk walking or biking - or some kind of "passive" activity, such as watching a video or just sitting quietly.

Overall, Taylor's team found, people said they had less desire to smoke after working out than they did before.

Exactly why is not clear. Exercise may serve as a distraction, while being active might also boost people's mood, so that they don't feel as great a need to feel better by smoking, Taylor said.

None of the smokers in the studies was in a quit program or using nicotine replacement products, such as gums or patches. Since nicotine replacement therapy curbs cravings, exercise might have less of an effect on smokers using these products. SOURCE: bit.l/SwF01w

(Reporting from New York by Amy Norton at Reuters Health; Editing by Elaine Lies and Michael Perry)

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