Cancer Exercise: Evaluation of a Mobile App in Breast Cancer Survivors

This study will examine whether a mobile app increases exercise levels in breast cancer survivors after treatments, reduces fatigue, and improves physical functions. This experimental study has 200 participants placed into one of two groups. One group will be asked to use the cancer-specific exercise app over 12 weeks, and the other group will receive the cancer exercise guidelines. Exercise will be measured by self-report questionnaires before and after the intervention and three months later. Self-report questionnaires will measure fatigue and quality of life. This research will determine whether a simple mobile app helps increase exercise in breast cancer survivors. Mobile apps to increase exercise may be provided to all breast cancer survivors after treatments to help them recover and possibly improve survival.

Exercise is beneficial for breast cancer survivors in alleviating treatment side effects, improving quality of life, and possibly survival. Exercise guidelines for cancer survivors recommend 150 minutes of moderate-intensity or 75 minutes of vigorous-intensity aerobic exercise per week and two days of resistance training. However, the number of breast cancer survivors meeting those guidelines declines during treatments because of symptoms such as fatigue, depression, muscle loss, and treatment toxicity. Mobile applications (apps) are promising tools with the potential to overcome barriers to exercise, such as cost, accessibility, time, and travel, which may reduce social health inequalities. Distanced-based interventions, including mobile apps, yield noteworthy results with favorable responses from cancer survivors. However, the literature provides few details regarding the content and features of mobile apps, hindering the understanding of the potential benefits for cancer survivors. The mobile app Cancer Exercise, developed based on Social-Cognitive Theory incorporating several evidence-based behavior change techniques, has been freely available to cancer survivors since 2020. No study to date has examined the efficacy of any existing mobile app for increasing exercise levels and improving outcomes of breast cancer survivors.

The primary aim of this study is to test the efficacy of the mobile app compared to usual care in increasing exercise levels in breast cancer survivors. The secondary aims are to (1) test the efficacy of the app for reducing fatigue and improving quality of life and physical function, (2) examine the effects of the app on motivation, and (3) determine if the app performs differently in diverse subgroups based on demographic (e.g., age, education, ethnicity, and geography) and clinical variables (e.g., disease stage, previous treatments). It was hypothesized that, compared to usual care, the Cancer Exercise app would improve exercise, fatigue, quality of life, physical function, and motivation, similarly across diverse subgroups.

Individuals diagnosed with stage I-III breast cancer (n=200) will be recruited through the Alberta Cancer Registry and randomly assigned to the app intervention (n=100) or usual care (n=100) receiving exercise guidelines. The goal of the intervention group will be to perform at least 90 minutes of aerobic exercise and two days of resistance exercise per week over 12 weeks. Exercise will be measured the Godin Leisure-Time Exercise Questionnaire at baseline, 12 weeks, and 6 months. The European Organization for Research and Treatment of Cancer (EORTC) core 30-item questionnaire (QLQ-C30) will measure quality of life. Analysis of covariance will compare outcomes between groups while adjusting for important demographic and clinical variables. Interactions (subgroup analysis) involving demographic and clinical variables will also be explored.

This research will provide the first evidence of the efficacy of a mobile app for increasing exercise in breast cancer survivors. The results will contribute to regulation in designing app-based exercise interventions to minimize the potential risk of injury and adverse outcomes for breast cancer survivors. With an effective and tested mobile app, healthcare providers may leverage this resource to facilitate safe and easy exercise referrals for patients.

Eligibility Criteria:
Inclusion Criteria:

* ≥ 18 years of age, diagnosed with histologically confirmed stage I, II, or III breast cancer, \> 1 to 5 years after diagnosis (2020-2024) and completed all treatments except hormone therapy, own a smartphone (Apple or Android), able to read and understand English, and interested in increasing exercise.

Exclusion Criteria:

* Not being medically cleared to participate in the exercise intervention by a certified exercise physiologist using the Physical Activity Readiness Questionnaire for Everyone (PAR-Q+) (e.g., known cardiac disease or uncontrolled hypertension), evidence of cancer recurrence, stage IV metastatic breast cancer and unable to walk without material or physical support.