"If we found the same effects in a drug, it would immediately be sold as an aid to help people quit smoking," said Dr. Adrian Taylor, the study's lead author and professor of exercise and health psychology at the University of Exeter.

Taylor and colleagues reviewed 12 papers looking at the connection between exercise and nicotine deprivation. They focused on exercises that could be done outside a gym, such as walking and isometrics, or the flexing and tensing of muscles. According to their research, just five-minutes of exercise was often enough to help smokers overcome their immediate need for a nicotine fix.

After various types of moderate physical exertion, researchers asked people to rate their need for a cigarette. People who had exercised reported reduced a desire.

"What's surprising is the strength of the effect," said Dr. Robert West, professor of health psychology at University College London. West was not involved in the review. "They found that the acute effects of exercise were as effective as a nicotine patch," he said.

West cautioned that it was unknown how long the effects of exercise would last. "You could in theory use exercise to deal with short bouts of nicotine cravings, but we don't know if it would help in the longer term," he said. It is likely that exercise would have to be combined with a larger strategy of other anti-smoking techniques to be successful in helping people quit.

Nearly anything that distracts people from smoking is thought to help, but scientists have long suspected that exercise might have a more potent effect. Taylor theorized that exercise could produce the mood-enhancing hormone dopamine, which could, in turn, reduce smokers' nicotine dependence.

Still, experts were not convinced about the study's practical applications. "Doctors can tell patients to do things until they're blue in the face, but the limiting factor may be getting people to actually take up exercise," said Dr. Peter Hajek, professor of clinical psychology at Queen Mary University Hospital in London. Hajek was not involved in the study.

Hajek said that if people were taught simple exercises, including isometric exercises they could do at their desk, they could potentially stave off their need for a cigarette break. "When you are dying for a cigarette, you can try to exercise instead," he said.