title: Age-related hormonal adaptations, muscle circumference and strength development with 8 weeks moderate intensity resistance training.
abstract: OBJECTIVE
  To examine the response of the endocrine system, strength development and muscle circumference to moderate-resistance training in younger and middle-aged men.
  
  
  METHODS
  Two groups of men of similar activity background, but differing in age (Y: 21.2±2.2years and M: 49.7±2.1years) participated in an 8-week moderate-resistance training program. Blood sampling was obtained at rest before and after training for analysis of serum testosterone, growth hormone, cortisol and ACTH concentrations. One repetition maximum for the bench press (1RM(BP)) and squat (1RM(S)); thigh (TC) and arm circumference (AC) were also measured. Both groups underwent a 1-h standardized moderate-resistance training session (three series of 8 to 15RM; nine exercises with 1-3min rest between sets) three times a week for 8weeks.
  
  
  RESULTS
  Both the Y and M groups gained significant improvements in 1RM(BP), 1RM(S), TC and AC (P<0.05). Growth hormone and testosterone concentration increased for both groups, while Y men increased greater than M men in resting posttraining testosterone concentration. With training the Y and M men demonstrated significant decreases in ACTH and cortisol concentrations.
  
  
  CONCLUSIONS
  These data indicate moderate-resistance training would lead to gains in maximal strength, muscle circumference and increases anabolic hormone secretion for M men and consequently promoting of health, improve daily life and delay negative effects with aging.
authors: Department of Exercise Physiology, Faculty of Physical Education and Sport Sciences, University of Guilan, PO Box 1438, Rasht, Iran. hamidarazi@yahoo.com
authors: Hamid
authors: H
authors: Arazi
authors: Arsalan
authors: A
authors: Damirchi
authors: Abbas
authors: A
authors: Asadi
mesh_terms: D000222:Adaptation, Physiological / Q000502:physiology*; D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000375:Aging / Q000097:blood / Q000378:metabolism / Q000502:physiology; D015444:Exercise / Q000502:physiology; D006728:Hormones / Q000097:blood* / Q000378:metabolism; D006801:Humans; D008297:Male; D008875:Middle Aged; D053580:Muscle Strength / Q000502:physiology*; D018482:Muscle, Skeletal / Q000254:growth & development*; D009929:Organ Size; D055070:Resistance Training; D055815:Young Adult
chemical_list: D006728:Hormones