Effectiveness of a self-monitoring app to support physical activity maintenance among rural Canadians with cancer after an exercise oncology program: results from a cluster randomized controlled trial (Preprint)

BACKGROUND Despite the benefits of exercise for individuals with cancer, most individuals remain insufficiently active. Supervised exercise oncology interventions can improve short-term PA levels. However, individuals often struggle to maintain PA levels post-intervention due to persistent psychological (motivation, confidence) and environmental (time, access to resources) PA barriers. Health technology (eHealth) may address some of these barriers and deliver effective, scalable PA interventions in oncology, yet research to date reports mixed effectiveness of eHealth to change PA. Importantly, the use of eHealth to support PA maintenance among rural cancer populations, who may need greater PA support given their lower PA levels and worse health outcomes, remains understudied. OBJECTIVE The study aim was to examine the effectiveness of an app-based self-monitoring intervention to support PA maintenance among rural cancer populations after a supervised online exercise oncology program. METHODS This 2-arm cluster-randomized controlled trial (RCT) was embedded within the Exercise for Cancer to Enhance Living Well (EXCEL) effectiveness-implementation study. Upon consenting, participants were randomized 1:1 by EXCEL class clusters to the intervention, 24-weeks of app-based PA self-monitoring, or waitlist control group, who received access to the app after 24-weeks. Both groups completed a 12-week supervised online exercise oncology program with twice weekly group-based classes, followed by a 12-week self-directed PA maintenance period. Baseline demographics, eHealth use and literacy, and patient-reported outcomes were compared using t-tests and chi-square tests. App use was measured throughout the intervention. The primary outcome, self-reported moderate-vigorous PA (MVPA) minutes, and secondary outcomes, objective MVPA minutes and steps, and app usability ratings, were collected at baseline, 12, and 24-weeks. Intervention effects on self-report MVPA maintenance were assessed via linear mixed modeling. Secondary outcomes were explored descriptively. RESULTS 205/359 eligible EXCEL participants consented, 199 (106 intervention, 93 control) started the study, and 183 (100 intervention, 83 control) and 141 (69 intervention, 72 control) completed measures at 12 and 24 weeks, respectively. Mean age was 57.3 ± 11.5. Most participants were female (87.4%), White (81.9%), and diagnosed with breast cancer (54.3%). Median baseline self-report MVPA minutes were 60.0 (IQR 0-180) and 40.0 (IQR 0-135) for the intervention and waitlist control groups, respectively (P=.74). Median app use duration was 10.3 (IQR 1.3-23.9) weeks with 9.6 (IQR 4.4-17.8) self-monitoring entries per week. Both groups increased MVPA significantly at 12 weeks (P<.001) and maintained increases at 24 weeks (P<.001), relative to baseline, with no between-group differences (p=0.87). Intervention group participants had significantly higher step counts for 7/12 PA maintenance period weeks (P=.048-<.001). CONCLUSIONS The present app-based self-monitoring intervention did not improve MVPA maintenance but may have contributed to increased step counts during the PA maintenance period. More work is needed to realize the full potential of eHealth in exercise oncology. CLINICALTRIAL NCT04790578