LAUSR

OBJECTIVE Evidence on the benefits of physical activity (PA) during cancer has caused a paradigm shift from people with cancer being advised to save energy (rest paradigm) to guidelines recommending them to engage in regular PA (activity paradigm). This study examined the rest and the activity paradigm among people with cancer based on the theory of planned behaviour (TPB). METHODS A cross-sectional survey was completed by N = 1244 people (58% women; M = 59.95 years) with breast, prostate and colorectal cancer, including 15 items on rest and activity attitudes. To explain the intention to engage in PA, hierarchical regression analyses were calculated. RESULTS The two-dimensional structure of attitudes (rest and activity) was confirmed. The agreement with the activity paradigm (M = 4.11; SD = 0.78) was higher compared to the rest paradigm (M = 2.56; SD = 0.78, p < .001). The TPB was an appropriate model to explain the intention to engage in PA (R2  = .59), showing that the activity paradigm, but not the rest paradigm, was significantly associated with participants' intention for PA. CONCLUSION Results indicate that the paradigm shift has successfully reached attitudes of people with cancer. Interventions focusing on the benefits of PA rather than addressing rest cognitions promise higher effectiveness in affecting PA levels. CLINICAL TRIAL REGISTRATION NUMBER NCT02678832.