Fourteen studies (n=1,126) were included in the review; 7 appeared to be randomised controlled trials, another one was a controlled trial, and 6 measured differences within individuals.
Nine of the 10 studies comparing the effects of an active and passive condition found a significant reduction in cigarette cravings during and after exercise. The ES for 5 of these studies assessing 'strength of desire to smoke' ranged from 0.50 to 2.07. For 7 of the studies the mean ES at 10 minutes post-treatment was 1.1 (SD=0.9). The effects of different intensities of exercise on cravings were compared in 3 studies, but only 1 reported statistically significant differences; these were in favour of more intense exercise. One study found that isometric exercise reduced cravings relative to a passive condition.
Eight of the 9 studies comparing the effects of an active and passive condition found a significant reduction in at least two withdrawal symptoms during and following exercise. The withdrawal symptoms that were shown to be reduced included stress, anxiety, tension, poor concentration, irritability and restlessness. One study using the Shiffman Withdrawal Scale failed to show a beneficial effect.
Three studies reported a significant improvement in mood and affect during and following exercise, and 1 reported no reduction in state anxiety following exercise.
With regard to smoking topography or behaviour, 4 studies reported a significant but variable increase in time to ad libitum smoking after exercise (ES ranged from 0.85 to 1.2, where reported in 3 studies). One study reported that exercise resulted in a reduction in the time spent holding the first cigarette smoked, and another found that stretching/isometric exercise resulted in a reduction in the number of puffs taken from the first cigarette smoked after exercise.
With regard to responses to cue-elicited cravings, 1 study found that exercise attenuated increases in blood-pressure and the strength of desire to smoke, and an improvement in Mood and Physical Symptoms Scale (MPSS) items such as tension, stress and poor concentration in response to a lit cigarette, and a decrease in restlessness in response to the Stroop task. In contrast, another study found an increase in the desire to smoke following exercise in response to exposure to a lit cigarette.