Breast cancer survivors (BCS) undergo different types of surgery (e.g. lumpectomy, partial mastectomy, bilateral mastectomy) that may impair physical fitness. Regular participation in exercise is an effective strategy to improve physical fitness after surgery in BCS. The purpose of this study is to examine whether surgery type influences the effects of a 16-week exercise intervention on physical fitness in BCS.

Sedentary, overweight/obese (BMI>25kg/m²) BCS (Stages I–III) were enrolled as part of a larger ongoing RCT. BCS underwent supervised, progressive moderate-to-vigorous aerobic and resistance exercise sessions 3 times/week for 16 weeks. Cardiorespiratory fitness (CRF) and muscular strength (MS) were assessed at baseline and post-intervention. CRF was measured by calculating estimated VO₂max using the 4-minute walk test. MS was assessed from 10-RM (repetition maximum) tests of the leg extension (LE), leg flexion (LF), chest press (CP), and lat pulldown (LP) to estimate 1-RM values. Surgery type was abstracted from medical records. Paired t-test and one-way ANOVA were used to examine the effects of exercise training and surgery variables on physical fitness.

Forty-six (52.7±10.4y), primarily postmenopausal (56.1%), Hispanic (63.1%) BCS completed the intervention. CRF (mean % change 20.1±7.2%) and MS (LE: 42.6±28.1%; LF: 43.9±21.4%; CP: 58.5±55.0%; LP: 35.4±14.1%) significantly increased following the intervention (P<0.01). Post-intervention, MS was significantly higher in BCS who had mastectomy surgery when compared to those who had lumpectomy surgery (P<0.001).

Surgery type may impact improvements in physical fitness following a structured exercise intervention in BCS. Further research is required to understand whether surgical history impacts the effect of exercise on physical fitness in BCS.