ORIGINAL ARTICLE A prospective study of the determinants of exercise in bladder cancer survivors using the Theory of Planned Behavior Kristina H. Karvinen & Kerry S. Courneya & Ronald C. Plotnikoff & John C. Spence & Peter M. Venner & Scott North Received: 13 December 2007 / Accepted: 8 May 2008 / Published online: 6 June 2008 # Springer-Verlag 2008 Abstract Goals of work Although exercise has gained recognition as an effective supportive care intervention for cancer survi- vors, exercise participation rates are low. The present study examined the determinants of exercise in bladder cancer survivors using the Theory of Planned Behavior (TPB). Patients and methods Bladder cancer survivors (N =397) residing in Alberta, Canada completed a mailed question- naire at baseline that assessed demographic, medical, behavioral, and social cognitive variables and a second questionnaire 3 months later that assessed exercise. Multi- ple regression was the primary analysis. Main results Adjuvant therapy (r = -0.10, p =0.021), cancer invasiveness (r = -0.10, p =0.051), and age (r = -0.11, p = 0.037) were all negatively associated with exercise. Intention (β =0.25, p <0.001), perceived behavioral control (β =0.18, p =0.001), and planning (β =0.12, p =0.018) explained 20.9% of the variance in exercise over a 3-month period. Perceived behavioral control (β =0.32, p <0.001), affective attitude (β =0.18, p =0.002), instrumental attitude (β =0.15, p =0.025) and descriptive norm (β =0.10, p = 0.032) explained 39.1% of the variability in exercise intention. Constructs from the TPB mediated the associa- tions between adjuvant therapy, cancer invasiveness, age, and exercise. Age and adjuvant therapy also moderated some of the associations within the TPB. Conclusions Some medical and demographic variables predict exercise behavior in bladder cancer survivors, but these associations are mediated by the TPB. Interventions based on the TPB may be effective for promoting exercise in this cancer survivor population. Keywords Bladder cancer . Exercise . Determinants Introduction Exercise has gained recognition as a supportive care intervention for cancer survivors by improving a number of quality-of-life parameters in the physical, functional, and emotional domains [38]. Despite evidence of these benefits, exercise rates have been found to be lower in cancer survivors than in non-cancer patient controls [10]. Recent studies indicate that approximately 70 to 80% of cancer survivors do not exercise sufficiently after treatments [13, 27, 42]. Thus, it is important to identify determinants of exercise among cancer survivors to gain a better under- standing of exercise motivation and for the future design of exercise behavior change interventions. Support Care Cancer (2009) 17:171–179 DOI 10.1007/s00520-008-0471-8 K. H. Karvinen : K. S. Courneya : R. C. Plotnikoff : J. C. Spence Faculty of Physical Education & Recreation, E488 Van Vliet Centre, University of Alberta, Edmonton, AB, Canada T6G 2H9 R. C. Plotnikoff Centre for Health Promotion Studies, School of Public Health, University of Alberta, Edmonton, AB, Canada T6G 2H9 P. M. Venner : S. North Department of Medical Oncology, Cross Cancer Institute, 11560 University Avenue, Edmonton, AB, Canada T6G 1Z2 K. H. Karvinen (*) Department of Exercise and Sport Science, East Carolina University, 173 Minges Coliseum, Greenville, NC 27858, USA e-mail: karvinenk@ecu.edu