Physical activity intervention benefits persist months post-intervention: randomized trial in breast cancer survivors.

Purpose: Determine durable effects of the 3-month Better Exercise Adherence after Treatment for Cancer (BEAT Cancer) physical activity (PA) behavior change intervention 12 months post-baseline (i.e., 9 months after intervention completion).

Methods: This 2-arm multicenter trial randomized 222 post-primary treatment breast cancer survivors to BEAT Cancer (individualized exercise and group education) vs. usual care (written materials). Assessments occurred at baseline, 3, 6, and 12 months, with the 12 months assessment reported here. Measures included PA (accelerometer, self-report), cardiorespiratory fitness, muscle strength, body mass index, Functional Assessment of Cancer Therapy (FACT), SF-36, fatigue, depression, anxiety, satisfaction with life, Pittsburgh Sleep Quality Index (PSQI), lower extremity joint dysfunction, and perceived memory.

Results: Adjusted linear mixed-model analyses demonstrated statistically significant month 12 between-group differences favoring BEAT Cancer for weekly minutes of moderate-to-vigorous self-report PA (mean between-group difference (M) = 44; 95% confidence interval (CI) = 12 to 76; p = .001), fitness (M = 1.5 ml/kg/min; CI = 0.4 to 2.6; p = .01), FACT-General (M = 3.5; CI = 0.7 to 6.3; p = .014), FACT-Breast (M = 3.6; CI = 0.1 to 7.1; p = .044), social well-being (M = 1.3; CI = 0.1 to 2.5; p = .037), functional well-being (M = 1.2; CI = 0.2 to 2.3; p = .023), SF-36 vitality (M = 6.1; CI = 1.4 to 10.8; p = .011), fatigue (M =  - 0.7; CI =  - 1.1 to - 0.2; p = .004), satisfaction with life (M = 1.9; CI = 0.3 to 3.5; p = .019), sleep duration (M =  - 0.2; CI =  - 0.4 to - 0.03, p = .028), and memory (M = 1.1; CI = 0.2 to 2.1; p = .024).

Conclusions: A 3-month PA intervention resulted in statistically significant and clinically important benefits compared to usual care at 12 months.

Implications For Cancer Survivors: Three months of individualized and group PA counseling causes benefits detectable 9 months later.

Trial Registration: ClinicalTrials.gov NCT00929617 ( https://clinicaltrials.gov/ct2/show/NCT00929617 ; registered June 29, 2009).