Serum basal hormone concentrations, nutrition and physical fitness during strength and/or endurance training in 39-64-year-old women

Abstract

We examined effects of 21 weeks of strength and/or endurance training and nutrition on serum hormones and physical fitness in 39-64-year-old women. Subjects (n=79) were randomized into the endurance group (E), strength group (S), combined group (SE) and controls (C). Total body strength training and high-intensity bicycle training were used. Average energy and nutrient intake remained the same in all groups. Body fat (dual energy X-ray absorptiometry) decreased significantly in all training groups and body mass index in E, SE and C. Only SE increased total body lean mass (2.2%, p=0.001), between groups p=0.044. Maximal cycling power increased more in E (16%) and SE (17%) than in S (8%)(all p<0.001), between groups p<0.001. Knee extension strength increased only in S (7%, p=0.006) and SE (11%, p<0.001). The changes in serum hormones did not differ between the groups, except insulin-like growth factor-1 (p=0.028), characterized by an 8% (p=0.097) increase in SE and a 7% (p=0.074) decrease in C. In women combined training led to marked improvements in physical fitness and body composition. Energy and protein intake was sufficient to ensure training-induced adaptations in muscle mass and physical fitness in response to both endurance and strength training, even though the energy balance was slightly negative in the endurance-trained groups.