Motivation for Different Types and Doses of Exercise During Breast Cancer Chemotherapy: a Randomized Controlled Trial

Background: Exercise is beneficial for breast cancer patients during chemotherapy, but their motivation to perform different types and doses of exercise is unknown. Purpose: The purpose of this study was to examine the anticipated and experienced motivation of breast cancer patients before and after three different exercise programs during chemotherapy. Methods: Breast cancer patients initiating chemotherapy (N = 301) were randomized to a standard dose of 25–30 min of aerobic exercise, a higher dose of 50–60 min of aerobic exercise, or a combined dose of 50–60 min of aerobic and resistance exercise. Patient preference and motivational outcomes from the theory of planned behavior (i.e., perceived benefit, enjoyment, support, difficulty, and motivation) were assessed before and after the interventions. Results: At pre-randomization, breast cancer patients were significantly (p < 0.001) more likely to prefer the combined program (80.1 %); however, after the interventions there was a significant (p < 0.001) increase in the number of patients preferring the high volume program and having no preference. At pre-randomization, breast cancer patients anticipated more favorable motivational outcomes for the combined program and less favorable motivational outcomes for the high volume program (all p < 0.001). After the interventions, the motivational outcomes experienced exceeded the anticipated motivational outcomes significantly more in the high volume group than the standard or combined groups. Conclusions: Anticipated motivational outcomes for different types and doses of exercise during chemotherapy varied considerably at pre-randomization, but the motivational outcomes experienced after the three interventions were similar. Clinicians can recommend any of the three exercise interventions to breast cancer patients knowing that positive motivational outcomes will result. Clinicaltrials.gov identifier: NCT00249015.