Hormonal responses to resistance exercise in long-term trained and untrained middle-aged men.
This cross-sectional study compared hormonal responses to resistance exercise between trained and untrained men to investigate the adaptations of the endocrine system to long-term strength training in middle-aged men. Twenty-one middle-aged men were recruited for this study and matched into a strength-trained group (SG) (n = 10) and an untrained group (UG) (n = 11). In the SG, the individuals had practiced strength training for hypertrophy for at least 3 years. Upper- and lower-body muscle strength was measured with a 1 repetition maximum (1RM) test. Blood samples were collected at rest and after multiple sets of a superset strength training protocol (SSTP), with an intensity of 75% of 1RM values. With these blood samples, the levels of total testosterone (TT), free testosterone (FT), dehydroepiandrosterone (DHEA), cortisol, and sex hormone-binding globulin (SHBG) were determined. In addition, the TT-to-cortisol ratio and TT-to-SHBG ratio were calculated. There was no difference at rest between groups in hormonal values for TT, FT, DHEA, cortisol, the TT-to-SHBG ratio, and the TT-to-cortisol ratio. There were increases after SSTP in the levels of TT, FT, DHEA, and cortisol and the TT-to-SHBG ratio in the UG, but only FT increased in the SG. The SG demonstrated lower values in the TT-to-SHBG ratio after the training session. These results suggest the presence of alterations in anabolic and catabolic hormonal responses to resistance exercise in long-term trained middle-aged men, with the trained subjects demonstrating lower responsiveness in the hormone values. Long-term trained men seem to require a higher volume of training, at least similar to their daily workout, to stimulate greater hormone responses.
Cadore
Eduardo Lusa
EL
Exercise Research Laboratory, Physical Education School, Federal University of Rio Grande do Sul, Porto Alegre, Brazil. edcadore@yahoo.com.br
Lhullier
Francisco Luiz Rodrigues
FL
Brentano
Michel Arias
MA
da Silva
Eduardo Marczwski
EM
Ambrosini
Melissa Bueno
MB
Spinelli
Rafael
R
Silva
Rodrigo Ferrari
RF
Kruel
Luiz Fernando Martins
LF
D000222:Adaptation, Physiological; D000328:Adult; D000704:Analysis of Variance; D015415:Biomarkers / Q000097:blood*; D001823:Body Composition; D003430:Cross-Sectional Studies; D003687:Dehydroepiandrosterone / Q000097:blood; D006728:Hormones / Q000097:blood*; D006801:Humans; D006854:Hydrocortisone / Q000097:blood; D008297:Male; D008875:Middle Aged; D053580:Muscle Strength / Q000502:physiology; D055070:Resistance Training / Q000379:methods*; D012738:Sex Hormone-Binding Globulin / Q000378:metabolism; D013739:Testosterone / Q000097:blood
D015415:Biomarkers; D006728:Hormones; D012738:Sex Hormone-Binding Globulin; D013739:Testosterone; D003687:Dehydroepiandrosterone; D006854:Hydrocortisone