Hypothalamic‐Pituitary‐Adrenal Axis Responses to an Acute Bout of Moderate Intensity Aerobic Exercise in Breast Cancer Survivors

Abstract

The purpose of this investigation was to examine the effect of one 30‐minute bout of moderate intensity aerobic exercise on hypothalamic‐pituitary‐adrenal (HPA) axis hormone responses in women with and without a history of breast cancer. Study participants included 21 women between the ages of 40–75 years, 11 of whom had completed treatments for Stage I–III invasive breast cancer (breast cancer survivors) and 10 of whom did not have a history of cancer diagnosis or treatment (controls). Participants completed a 30‐minute session of aerobic exercise on the cycle ergometer at a workload corresponding to 60% of VO2peak. Blood samples were taken pre‐exercise, immediately post‐exercise, and 30 minutes post‐exercise. Plasma concentrations of corticotropin releasing hormone (CRH), adrenocorticotropic hormone (ACTH), and cortisol were measured at each time point using enzyme‐linked immunosorbent assay (ELISA) techniques (Biotang, Inc., Lexington, MA). Data were compared between groups using Mann‐Whitney U tests and across time using Wilcoxon Signed‐Rank tests. Physical characteristics (e.g. age, height, body mass, BMI, percent body fat and VO2peak) were similar between breast cancer survivors and controls (56 ± 8 years vs. 56 ± 7 years; 163.1 ± 5.3 cm vs. 165.7 ± 5.7 cm; 66.8 ± 9.9 kg vs. 77.0 ± 19.0 kg; 25.1 ± 4.1 kg/m2 vs. 28.1 ± 7.3 kg/m2; 31.1 ± 5.3% vs. 33.4 ± 6.6%; and 21.7 ± 6.8 mL/kg/min vs. 24.3 ± 9.8 mL/kg/min, respectively; p = 0.193–0.973). Cortisol was somewhat elevated immediately post‐exercise in breast cancer survivors relative to controls (Table 1, p = 0.085). CRH decreased significantly at 30 minutes post‐exercise relative to immediately post‐exercise values in breast cancer survivors (Table 1, p= 0.003). ACTH decreased somewhat at 30 minutes post‐exercise relative to immediately post‐exercise values in both groups (p = 0.091 and 0.059 for breast cancer survivors and controls, respectively). All other CRH, ACTH, and cortisol responses were similar between groups and across time (p = 0.114–0.929). These results suggest that one 30‐minute session of moderate intensity aerobic exercise has largely similar effects on hormonal responses of the HPA axis in women with and without a history of breast cancer. These preliminary findings continue to demonstrate that moderate aerobic exercise is well tolerated in breast cancer survivors, thus supporting current exercise recommendations for this population.Support or Funding InformationThis work was supported by Elon University Faculty Research and Development funds.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.