Effects of the BEAT Cancer physical activity behavior change intervention on physical activity, aerobic fitness, and quality of life in breast cancer survivors: a multicenter randomized controlled trial

Abstract

Most breast cancer survivors (BCS) are not meeting recommended physical activity guidelines. Here, we report the effects of the Better Exercise Adherence after Treatment for Cancer (BEAT Cancer) behavior change intervention on physical activity, aerobic fitness, and quality of life (QoL). We randomized 222 post-primary treatment BCS to the 3-month intervention (BEAT Cancer) or usual care (UC). BEAT Cancer combined supervised exercise, face-to-face counseling, and group discussions with tapering to home-based exercise. Assessments at baseline, immediately post-intervention (month 3; M3), and 3 months post-intervention (month 6; M6) included accelerometer and self-reported physical activity, submaximal treadmill test, and QoL [Functional Assessment of Cancer Therapy (FACT)-Breast scale]. Adjusted linear mixed-model analyses demonstrated significant effects of BEAT Cancer compared to UC on weekly minutes of ≥ moderate intensity physical activity at M3 by accelerometer [mean between group difference (M) = +41; 95 % confidence interval (CI) = 10-73; p = 0.010] and self-report (M = +93; CI = 62-123; p < 0.001). Statistical significance remained at M6 for self-reported physical activity (M = +74; CI = 43-105; p < 0.001). BEAT Cancer participants were significantly more likely to meet physical activity recommendations at both time points [accelerometer M3 adjusted odds ratio (OR) = 2.2; CI = 1.0-4.8 and M6 adjusted OR = 2.4; CI = 1.1-5.3; self-report M3 adjusted OR = 5.2; CI = 2.6-10.4 and M6 adjusted OR = 4.8; CI = 2.3-10.0]. BEAT Cancer significantly improved fitness at M6 (M = +1.8 ml/kg/min; CI = 0.8-2.8; p = 0.001) and QoL at M3 and M6 (M = +6.4; CI = 3.1-9.7; p < 0.001 and M = +3.8; CI = 0.5-7.2; p = 0.025, respectively). The BEAT Cancer intervention significantly improved physical activity, fitness, and QoL with benefits continuing 3 months post-intervention.

Fig. 1

Participants’ flow through the study (note: more than one reason for ineligibility possible)

Fig. 2

BEAT Cancer intervention effects on physical activity immediately post-intervention (month 3) and 3 months later. Legend: 3 months = immediately post-intervention, 6 months = 3 months after intervention completion; minutes of vigorous activity doubled before adding to minutes of moderate intensity; adjusted least square means with standard error bars provided for month 3 and month 6 only because baseline used as covariate in the model (see text for list of all covariates); a accelerometer measuring free-living physical activity and b self-report measuring leisure-time physical activity only

Fig. 3

BEAT Cancer intervention effects on cardiorespiratory fitness immediately post-intervention (month 3) and 3 months later. Legend: 3 months = immediately post-intervention, 6 months = 3 months after intervention completion; adjusted least square means with standard error bars provided for month 3 and month 6 only because baseline used as covariate in the model (see text for list of all covariates)

Fig. 4

BEAT Cancer intervention effects on quality of life immediately post-intervention (month 3) and 3 months later. Legend: 3 months = immediately post-intervention, 6 months = 3 months after intervention completion; adjusted least square means with standard error bars provided for month 3 and month 6 only because baseline used as covariate in the model (see text for list of all covariates); a Functional Assessment of Cancer Therapy (FACT)-Breast and b FACT physical well-being subscale