Changes in Lower Body Functional Strength after Physical Activity Intervention in Sedentary Low Income Breast Cancer Survivors

Abstract

Studies show physically active breast cancer survivors (BCS) can reduce risk of breast cancer (BC) recurrence and BC-related mortality. Physical activity (PA) can help reduce many quality of life (QOL) concerns reported by BCS. Reviews of PA for cancer survivors report interventions improved aerobic fitness, body strength, BMI, and QOL. PURPOSE: Examine changes in lower body functional strength (LBFS) after a 16 week PA intervention in inactive, low-income BCS. Consideration of LBFS is imperative in establishing an active lifestyle which can lead to greater QOL and reduce risk of cancer recurrence. METHODS: Participants (PTS) were low-income, underinsured BCS from the Houston, TX area with less than 150 minutes of moderate PA a week. An in-person PA program was delivered in 12 group sessions over 16 weeks. This included 10 minutes of PA to instruct on intensity, resistance tubes use, and PA safety. PTS were asked to complete 30 minutes of moderate or greater intensity PA 5 or more days a week, and include 2 days resistance training weekly. The short International Physical Activity Questionnaire (IPAQ) (baseline (BL), follow up (F/U)) was used to measure if PTS met PA criteria. The 6 minute walk test (6MWT) and 30 second sit-to-stand (Rikli and Jones Senior Fitness test Manual) were used at BL and F/U to assess lower body physical function (LBPF). RESULTS: We examined 35 PTS, mean age 59, median education some college. IPAQ results show significant increase in PA between BL and F/U in all categories of intensity: walk (p = .018), moderate (p = .007), vigorous (p = .009). We observed significant increase in 30 second sit-to-stand count (p = .045) but not 6MWT (p = .141). Paired t-tests were used between BL and F/U. CONCLUSION: Results suggest PA including guidance in increasing PA can produce positive changes in PA on all intensity levels. Initial gains LBFS may be attributed to newly introduced resistance activity and resulting muscle adaptation. While no significant results were seen in 6MW, gains in LBFS show potential for gains in overall (LBPF) with a well-planned PA program involving progressive overload for aerobic conditioning leading to more PA and better QOL. Funded by the Cancer Research Institute of Texas (CPRIT). Acknowledgements: Center for Energy Balance in Cancer Prevention and Survivorship, Kelsey Research Foundation