The overall purpose of this pilot study is to examine effects of Hatha yoga and cardiovascular exercise on craving, mood, cue reactivity, and smoking behavior. Our preliminary study indicated that a single session of either form of activity intervention improved mood, and the yoga intervention appeared to decrease cravings to smoke. The proposed study will extend this preliminary research in several ways.

First, the investigators will expand the exercise-based interventions from one to three sessions, which will more closely resemble how these interventions may be used in the context of smoking cessation. Second, the investigators will recruit smokers who are motivated to quit smoking, further increasing the clinical relevance of the research. Finally, the investigators will examine the effects of the interventions on actual smoking behavior within and outside of the laboratory setting. This may appropriately be considered a "proof of concept" study, as the investigators will not be powered to detect treatment outcome (smoking cessation) differences, nor are the interventions designed to maximize clinical smoking cessation outcomes.

Participants will be randomized to receive 3-sessions of yoga instruction, 3-sessions of cardiovascular exercise, or to a no activity control group. Sessions will be scheduled to occur approximately 7 days apart, with a minimum of 4 between sessions. Mood and craving will be assessed before and after each session, and smoking behavior will be assessed following each session. Finally, a detailed cue reactivity assessment will be conducted prior to the first session and following the last session. Analyses will examine intervention effects on craving, mood, cue reactivity, and smoking behavior. In addition, the investigators will examine several potential mediators and moderators of intervention effects on smoking behavior. Finally, the investigators will continue to examine the feasibility and potential acceptability of each active intervention, to assist in developing future clinical applications of these techniques in the context of smoking cessation.

Inclusion Criteria:

• Smoke at least 10 cigarettes per day
• Smoked regularly at least 2 years
• Carbon monoxide reading at least 8 ppm
• Interest in quitting smoking
• Able to read and understand the consent form and questionnaires
• Not currently practicing yoga

Exclusion Criteria:

• Current Diagnostic and Statistical Manual of Mental Disorders IV (DSM-IV) (American Psychiatric Association, 1994) psychosis
• Major depressive episode, manic episode, or panic disorder
• Current DSM-IV psychoactive substance dependence or use
• Current medication use that might affect physiological responses
• Current use of bupropion, varenicline, or nicotine-containing products other than cigarettes
• Significant health problems that might compromise physiological data collection or be contraindicated for moderate physical exercise or yoga
• Significant hearing or visual impairment; pregnant as determined by urine human chorionic gonadotropin (hCG) test or nursing females
• Body mass index (BMI) 35 or greater