title: Endogenous anabolic hormonal and growth factor responses to heavy resistance exercise in males and females.
abstract: To examine endogenous anabolic hormonal responses to two different types of heavy resistance exercise protocols (HREPs), eight male and eight female subjects performed two randomly assigned protocols (i.e. P-1 and P-2) on separate days. Each protocol consisted of eight identically ordered exercises carefully designed to control for load, rest period length, and total work (J) effects. P-1 utilized a 5 RM load, 3-min rest periods and had lower total work than P-2. P-2 utilized a 10 RM load, 1-min rest periods and had a higher total work than P-1. Whole blood lactate and serum glucose, human growth hormone (hGH), testosterone (T), and somatomedin-C [SM-C] (i.e. insulin-like growth factor 1, IGF-1) were determined pre-exercise, mid-exercise (i.e. after 4 of the 8 exercises), and at 0, 5, 15, 30, and 60 min post-exercise. Males demonstrated significant (p less than 0.05) increases above rest in serum T values, and all serum concentrations were greater than corresponding female values. Growth hormone increases in both males and females following the P-2 HREP were significantly greater at all time points than corresponding P-1 values. Females exhibited significantly higher pre-exercise hGH levels compared to males. The P-1 exercise protocol did not result in any hGH increases in females. SM-C demonstrated random significant increases above rest in both males and females in response to both HREPs.(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Exercise Physiology Division, U.S. Army Research Institute of Environmental Medicine, Natick, MA 01760-5007.
authors.forename: W J
authors.initials: WJ
authors.lastname: Kraemer
authors.forename: S E
authors.initials: SE
authors.lastname: Gordon
authors.forename: S J
authors.initials: SJ
authors.lastname: Fleck
authors.forename: L J
authors.initials: LJ
authors.lastname: Marchitelli
authors.forename: R
authors.initials: R
authors.lastname: Mello
authors.forename: J E
authors.initials: JE
authors.lastname: Dziados
authors.forename: K
authors.initials: K
authors.lastname: Friedl
authors.forename: E
authors.initials: E
authors.lastname: Harman
authors.forename: C
authors.initials: C
authors.lastname: Maresh
authors.forename: A C
authors.initials: AC
authors.lastname: Fry
mesh_terms: D000222:Adaptation, Physiological; D000328:Adult; D000704:Analysis of Variance; D015444:Exercise / Q000502:physiology*; D005260:Female; D013006:Growth Hormone / Q000097:blood*; D006801:Humans; D007773:Lactates / Q000097:blood; D019344:Lactic Acid; D008297:Male; D012737:Sex Factors; D013002:Somatomedins / Q000378:metabolism*; D013739:Testosterone / Q000097:blood
chemical_list: D007773:Lactates; D013002:Somatomedins; D019344:Lactic Acid; D013739:Testosterone; D013006:Growth Hormone