Body Composition, Strength And Physical Function In Short- And Long-term Breast Cancer Survivors

Abstract

Previous data have found that breast cancer survivors (BCS) have poorer body composition, strength, and physical function compared to age and weight matched controls. Whether these changes improve over time after treatment remains uncertain. PURPOSE: To compare body composition, strength, and physical function between short-term (ST; <4 years; n=17; age=57±9 yrs) and long-term (LT; >4 years; n=24; age=62±7 yrs) BCS. METHODS: Body composition [lean mass (LM), fat mass (FM)] was assessed using dual-energy X-ray absorptiometry. Lower body strength was assessed using the Biodex leg extension/flexion system at 60 ° isometric knee extension. Upper body strength was assessed using one repetition maximum chest press. Physical function was measured using the continuous-scale physical function performance test. Independent t-tests were used to compare ST and LT-BCS. Significance was accepted at p ≤ 0.05. RESULTS: Time since treatment completion was 1.8±1.0 yrs for ST and 11.8±6.9 yrs for LT. There were no differences in body weight, LM, FM, and upper and lower body strength between groups. Total physical function (ST:64±14; LT:73±11 U) and the functional domains for endurance (ST:66±15; LT:75±12 U) and balance (ST:65±15; LT:75±12 U) were significantly lower in ST-BCS. CONCLUSION: Our findings indicate that without exercise, body composition and strength do not improve whereas physical function improves over time following treatment. Funding: ACSM Doctoral Student Grant; NSCA Doctoral Graduate Student Research Grant.