The intervention successfully increased PA and improved fitness and specific aspects of psychological well-being among early-stage breast cancer patients. The success of a home-based PA intervention has important implications for promoting recovery in this population.

Objective: Evidence of the benefits of exercise for those treated for cancer has led to exercise interventions for this population. Some have questioned whether cancer patients offered a home-based intervention adhere to the exercise prescribed.Method: We examined exercise adherence in a randomized controlled trial of a 12-week, home-based exercise trial for breast cancer patients. Three adherence outcomes were examined: minutes of exercise participation=week, number of steps taken during planned exercise=week, and whether the participant met her weekly exercise goal. Predictors of adherence (e.g. demographic and medical variables, Transtheoretical Model variables, history of exercise) were examined.Results: Findings indicate that participants significantly increased their minutes of exercise and steps taken during planned exercise from Week 1 to 12. The percentage of participants achieving exercise goals was highest in the first few weeks. Exercise self-efficacy significantly predicted each adherence outcome. Baseline PA predicted mean exercise session steps over the 12 weeks.Conclusion: Adherence to a home-based exercise intervention for breast cancer patients changes over time and may be related to baseline levels of exercise self-efficacy.