title: Acute hormonal responses to two different fatiguing heavy-resistance protocols in male athletes.
abstract: To examine endogenous hormonal responses to heavy-resistance exercise, ten male strength athletes performed two fatiguing but different types of sessions on separate days. In session A the loads for the leg extensor muscles in the squat-lift exercise were maximal so that the subjects performed 20 sets at 1 repetition maximum (RM) (20 x 1 RM x 100%), whereas during session B the loads were submaximal (70%) but the subjects performed each of the 10 sets until the RM (i.e., 10 repetitions/set or 10 x 10 x 70%). The recovery time between the sets was always 3 min. A decrease of 10.3 +/- 4.7% (P < 0.001) occurred in the squat-lift in 1 RM during session A, whereas session B led to a decrease of 24.6 +/- 18.9% (P < 0.001) in 10 RM. Increases in the concentrations of serum total and free testosterone (P < 0.05 and 0.05, respectively), cortisol (P < 0.001), and growth hormone (GH, P < 0.001) were observed during session B, whereas the corresponding changes during session A were statistically insignificant except for the relatively slight increase (P < 0.01) in serum GH level. The significant (P < 0.001) increase in blood lactate concentration during the two sessions correlated significantly (P < 0.01) with the increase in serum GH concentration. The morning values of serum testosterone and free testosterone were significantly (P < 0.05-0.001) lowered on the 1st and 2nd rest days after the sessions.(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Department of Biology of Physical Activity, University of Jyväskylä, Finland.
authors.forename: K
authors.initials: K
authors.lastname: Häkkinen
authors.forename: A
authors.initials: A
authors.lastname: Pakarinen
mesh_terms: D000328:Adult; D005221:Fatigue / Q000097:blood*; D013006:Growth Hormone / Q000097:blood; D006728:Hormones / Q000097:blood*; D006801:Humans; D006854:Hydrocortisone / Q000097:blood; D007773:Lactates / Q000097:blood; D019344:Lactic Acid; D008297:Male; D005082:Physical Exertion / Q000502:physiology*; D013739:Testosterone / Q000097:blood; D014891:Weight Lifting
chemical_list: D006728:Hormones; D007773:Lactates; D019344:Lactic Acid; D013739:Testosterone; D013006:Growth Hormone; D006854:Hydrocortisone