The effect of aerobic exercise on levels of growth hormone and 17-beta estradiol in middle-aged women with breast cancer

Breast cancer, is the most common type of cancer and the most common cause of death in middle-aged women in developed countries; Results also show that inactivity and hormonal changes increase the risk of breast cancer. The purpose of this research was to investigate the effect of eight weeks of aerobic exercise on the growth hormone and 17-beta estradiol levels in middle-aged women with breast cancer.
In this semi-experimental study, 15 women with breast cancer with mean age (44.46±17.15 years), Weight (70.53±5.18 kg) and body mass index (27.58±2.18 kg/m2) were selected through available sampling and considered as the experimental group. The exercise program was performed three sessions per week and every session during 40-60 minutes and with an intensity of 30%-60% heart rate reserve (HRR) for eight weeks. As all patients were fasting for 12 hours and did not have vigorous physical activity 24 hours, the levels of growth hormone and 17-beta estradiol were measured before and after eight weeks of aerobic exercise. Data were analyzed by paired samples t-test at a significance levels of P The growth hormone levels did not changed significantly after eight weeks of aerobic exercise (P=0.447), whereas 17-beta estradiol levels decreased significantly (P=0.000).
It seems that eight weeks of aerobic exercise can reduce one of the breast cancer markers (17-beta estradiol); so these training are recommended for the improving or prevention of the breast cancer.