Effects of a peer-led physical activity program on psychosocial outcomes among breast cancer survivors.

Objective: To examine the effects of three programs aimed at maintaining moderate-to-vigorous physical activity (MVPA) on breast cancer survivors' quality of life, physical functioning, fatigue and mood.

Methods: 161 survivors participated in a 12-month randomized controlled study and were assigned to one of three groups: Reach Plus, Reach Plus Message, or Reach Plus Phone. All participants received the same intervention for the first 3 months (weekly calls from peer coach) for MVPA adoption. In Months 4-9, Reach Plus monitored MVPA and received feedback reports. Reach Plus Message monitored MVPA and received weekly text/email messages and feedback reports. Reach Plus Phone participants monitored MVPA and received monthly calls from coaches and feedback reports. Intervention delivery ended at 9 months. Assessments were obtained at baseline, 3, 6, 9, and 12-months. Analyses used a series of longitudinal mixed effects models with subject-specific intercepts.

Results: All groups improved significantly across time on psychosocial measures. At 9 months, Reach Plus Message and Reach Plus Phone reported better physical functioning compared to Reach Plus (b = 8.27, 95% CI: [2.27, 14.27]; b = 4.89, 95% CI: [0.01, 10.53]) respectively). At 12 months, Reach Plus Message reported better physical functioning than Reach Plus (b = 4.52, 95% CI: [0.01, 9.75]. Participants who met national PA guidelines reported significantly lower fatigue and higher physical functioning (at 9 and 12 months), and improved mood (at 12 months).

Conclusions: MVPA maintenance via weekly messages or monthly coach calls improved physical functioning. Maintaining MVPA at or above national recommendations was associated with improved physical functioning, mood and less fatigue.