It is well documented that temporarily abstinent smokers who undergo an acute bout of moderate intensity exercise experience a reduction in nicotine craving and withdrawal. Conversely, available research in chronic exercise and smoking cessation does not reliably demonstrate that combining exercise with well established treatments increases smoking abstinence rates. The overall aim of this dissertation was to investigate mechanisms underlying the beneficial effects of exercise in a group of female smokers taking part in a 14 week exercise plus nicotine replacement therapy (NRT) patch programme. Determining how smokers may benefit from exercise has important implications for designing effective interventions. Three independent yet related studies were conducted. The specific aims of study one (Chapter two) were to determine whether an acute bout of exercise would further reduce craving and withdrawal symptoms in a group of female quitters using NRT, and to explore whether the magnitude of this relief would relate to quit success. It was demonstrated that exercise provided additional craving and withdrawal benefit for these quitters. Magnitude of relief was not found to be related to end of programme quit status. Study two (Chapter three) sought to examine what bearing exercise expectancy (EXP) and credibility (CRED) beliefs of recently quit smokers had on self-reported craving and withdrawal following an acute bout of exercise, and to compare participants\u27 beliefs regarding NRT and exercise as quit smoking aids. Results showed that high exercise EXP and/or exercise CRED were found to be related to craving relief. Participants believed both NRT and exercise to be effective cessation aids. Study three (Chapter four) examined whether participants reported using exercise as a relapse prevention aid, and how readily these two behaviours can be concurrently changed. It was demonstrated that participants were able to simultaneously increase their exercise behaviour and decrease their smoking behaviour. Exercise was not reportedly used as a relapse prevention strategy. Overall, the results of these studies provide evidence that exercise is a worthwhile adjunct smoking cessation treatment, and elucidate some of the reasons as to how it may help individuals quit smoking. The clinical implications of the findings are discussed throughout
