Smokers will complete questionnaires and smoking behaviour will be examined. After abstaining from smoking for approximately 18 hours, they will be randomized to a moderate intensity exercise group or passive sitting group. Smoking behaviour (time to first puff) will be assessed following treatment.

Lung cancer is the leading cause of cancer death in Canadians (Canadian Cancer Society, in which cigarette smoking is responsible for 85% of these cases. Smoking topography, a key facet of smoking behaviour, can be subjectively or objectively measured by quantifying puff volume, maximum puff velocity, interpuff interval, puff duration, number of puffs per cigarette, and the time to smoke a single cigarette. Smoking topography can estimate exposure to carcinogenic toxins present in cigarette smoking (Djordjevic, Hoffman, & Hoffman, 1997). Evidence exists to support that exercise modifies smoking topography (Katomeri & Taylor 2006; Mikhail, 1983; Reeser, 1983; Zacny & Stitzer, 1985).

Recently, Faulkner and colleagues (2011; N = 18) were the first to implement a handheld smoking topography device (CReSS Pocket) to measure smoking behaviour in the context of an acute bout of exercise after a temporary period of abstinence. They found that brisk walking influences an individual's smoking topography. In specific, participants assigned to the exercise condition smoked less per puff and took shorter puff durations, compared to the passive sitting condition. Overall, smoking topographical studies require further investigation due to methodological flaws in order to allow for the objective collection of smoking behaviour data and improved external validity in a sufficiently powered study. Furthermore, the role of cravings, withdrawal and affect as potential mediators of topographical changes due to exercise is a novel area of research.

Inclusion Criteria:

• 18 to 64 years of age
• Smoke 10 cigarettes or more per day
• Not have any medical condition that is contraindicative for exercise
• Not be pregnant or intending on being pregnant over the course of the study
• Be able to read and write in English
• Have a telephone or an email account so that they can be contacted
• Completed the Physical Activity Readiness Questionnaire (PAR-Q)
• Have Medical Doctor's clearance if they answer "YES" to one or more questions on the Physical Activity Readiness Questionnaire (PAR-Q)
• Have not been engaged in a serious quit attempt in the last six months
• Have been smoking for more than 2 years
• Must not be suffering from an illness (e.g. cold) that would affect their typical smoking behaviour

Exclusion Criteria:

• Contraindication to exercise (e.g., disability, unstable angina)
• On medication for physical and/or mental health reasons that would make compliance with the study protocol difficult or dangerous
• Have substance dependency problems (e.g., alcohol)
• Are pregnant
• Be younger than 18 years of age
• Be 64 years or older prior to completion of the study
• Have been engaged in a serious quit attempt in the last six months
• Have been smoking for less than 2 years
• Suffering from an illness (e.g. cold) that would affect their typical smoking behaviour