The aim of this study was to evaluate the impact of a twice-weekly strength training intervention on perceptions of body image in 234 breast cancer survivors (112 with lymphedema) who participated in the Physical Activity and Lymphedema (PAL) trial. The study population included two hundred and thirty-four women randomly assigned to twice-weekly strength training or control group that completed the 32-item Body Image and Relationships Scale (BIRS) at baseline and 12 months. Percent change in baseline to 12-month BIRS total and subscale scores, upper and lower body strength, and general quality of life (QOL) were compared by intervention status. A series of multiple linear regression models including indicator variables for subgroups based on age, marital status, race, education, BMI, and strength change were used to examine differential intervention impact by subgroup. Strength and QOL variables were assessed as mediators of the intervention effect on BIRS.
Results: Baseline BIRS scores were similar across intervention and lymphedema status. Significantly greater improvement in BIRS total score was observed from baseline to 12 months in treatment vs. control participants (12.0 vs. 2.0%; P < 0.0001). A differential impact of the intervention on the Strength and Health subscale was observed for older women (>50 years old) in the treatment group (P = 0.03). Significantly greater improvement was observed in bench and leg press among treatment group when compared to control group participants, regardless of lymphedema. Observed intervention effects were independent of observed strength and QOL changes. Twice-weekly strength training positively impacted self-perceptions of appearance, health, physical strength, sexuality, relationships, and social functioning. Evidence suggests the intervention was beneficial regardless of prior diagnosis of lymphedema. Strength and QOL improvements did not mediate the observed intervention effects.