title: Effect of physical training on age-related reduction of GH secretion during exercise in normally cycling women.
abstract: OBJECTIVE
  To evaluate whether prolonged physical activity (25 km/week running for 8 years) modifies GH decline.
  
  
  METHODS
  The GH response to maximal exercise on bicycle-ergometer was tested in younger (26-30 years) and older (42-46 years) healthy women. Each age group included 2 subgroups of 10 sedentary and 10 runners, which were compared. The workload was increased at 3 min intervals from time 0 until exhaustion. Subjects with a low maximal capacity (as established in a preliminary test) pedalled for 3-4 min against no workload at the beginning of the test, so that exercises lasted about 15 min in all individuals.
  
  
  RESULTS
  At exhaustion, heart rate and systolic pressure were significantly higher in sedentary than in trained subjects, whereas V(O(2)max), blood glucose and plasma lactate levels were similar in all groups. Exercise induced similar GH responses in younger sedentary and exercise-trained subjects and in older exercise-trained subjects, with mean peak levels 7.5 times higher than baseline. In contrast, in older sedentary women peak GH level was only 4.4 times higher than baseline and was significantly lower than in the other groups.
  
  
  CONCLUSIONS
  These data suggest that in women prolonged physical training exerts protective effects against age-dependent decline in GH secretion.
authors.affiliation: Department of Internal Medicine and Biomedical Sciences, Via A. Gramsci 14, 43100 Parma, Italy. vittorio.coiro@unipr.it
authors.forename: Vittorio
authors.initials: V
authors.lastname: Coiro
authors.forename: Riccardo
authors.initials: R
authors.lastname: Volpi
authors.forename: Dandolo
authors.initials: D
authors.lastname: Gramellini
authors.forename: Maria Ludovica
authors.initials: ML
authors.lastname: Maffei
authors.forename: Elio
authors.initials: E
authors.lastname: Volta
authors.forename: Andrea
authors.initials: A
authors.lastname: Melani
authors.forename: Paolo
authors.initials: P
authors.lastname: Chiodera
mesh_terms: D000328:Adult; D000375:Aging / Q000502:physiology*; D015444:Exercise / Q000502:physiology*; D005260:Female; D019382:Human Growth Hormone / Q000097:blood / Q000378:metabolism*; D006801:Humans; D008875:Middle Aged; D047648:Perimenopause; D057185:Sedentary Behavior
chemical_list: D019382:Human Growth Hormone