Resistance exercise training, hormone replacement therapy, lean and fat mass, and serum anabolic and catabolic hormones in non-obese and obese postmenopausal women

Abstract

The present study was designed to test the hypothesis that hormone replacement therapy (HRT) and exercise training would be related to differences in resting hormone levels in association with soft tissue composition changes in postmenopausal women. Estrone (E₁), estradiol (E₂), androstenedione (A-4), cortisol, growth hormone (GH) and insulin-like growth factor I (IGF-I) were determined along with estimates of lean soft tissue (LST) and fat mass in total and regional body by dual-energy x-ray absorptiometry in a cross-sectional sample of women on HRT (n = 38) and not on HRT (no HRT, n = 46) and in a 12 month longitudinal data of the effects of exercise training on these variables. Postmenopausal women aged 40-65 years who were on HRT and no HRT were randomized to exercise [HRT (EX+HRT) and no HRT (EX))] and no exercise [HRT (HRT) and no HRT (CONTROL)]. Subjects were further classified in non-obese and obese (>40% fat) resulting in the following groups: no EX (non-obese and obese) and EX (non-obese and obese). Obese HRT had significant higher E₁, E₂, and lower GH than non-obese HRT. IGF-I was lower in obese HRT compared to both non-obese HRT and no HRT. Non-obese HRT had higher cortisol than non-obese no HRT. Exercise training decreased E₁ and E₂ with no effect on GH, IGF-I, A-4 and cortisol. Exercise training without HRT increased total body, arms and legs LST and decreased % fat. Arm LST increased in EX+HRT and in both non-obese EX and obese EX. Leg LST and % fat increased and decreased, respectively, in non-obese EX. The following was concluded from the study: there were no HRT effect on LST: HRT resulted in high E₁, E₂, GH, and cortisol, and low IGF-I; obesity was positively related to E₂ and negatively related to GH and IGF-I; obesity in addition to HRT was associated with a greater decrease in IGF-I; HRT had no beneficial effect on LST gains and fat mass losses resulting from exercise training; our exercise training effectively increased arm LST but not leg LST in the obese; exercise training did not modify E₁, E₂, A-4, cortisol, GH and IGF-I.