title: A single set of low intensity resistance exercise immediately following high intensity resistance exercise stimulates growth hormone secretion in men.
abstract: OBJECTIVE
  The purpose of the present study was to examine the effects of an additional set immediately following high intensity resistance exercise on growth hormone (GH) response.
  
  
  METHODS
  Subjects (n=8) performed 4 resistance exercise protocols (bilateral knee extension exercise) on separate days. The protocols were categorized into 2 types of protocol, namely "Strength-up type (S-type)" and "Combination type (Combi-type)". The S-type was resistance exercise which consisted of 5 sets at 90% of 1 repetition maximum (RM) with 3-min rest periods between sets, whereas the Combi-type is a training protocol which adds an additional set (either 50% of 1 RM [C50-type], 70% of 1 RM [C70-type] or 90% of 1 RM [C90-type]) to the S-type. Serum GH concentration and blood lactate concentration were determined pre-exercise and at 0-60 min postexercise. Relative changes in thigh girth and maximal unilateral isometric strength were determined pre-exercise and immediately postexercise.
  
  
  RESULTS
  The increasing values of GH concentration (DGH) in the S-type was the lowest of all protocols. On the other hand, DGH in the C50-type showed a significantly (p<0.05) higher increase than in the S-type and C90-type, and a relatively higher increase than in the C70-type.
  
  
  CONCLUSIONS
  These results suggests that a high intensity, low volume training protocol to induce neural adaptation resulted in little GH response, but GH secretion was increased by performing a single set of low intensity resistance exercise at the end of a series of high intensity resistance sets.
authors.affiliation: Doctoral Program in Health and Sport Sciences, University of Tsukuba, Tsukuba, Ibaraki, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Goto
authors.forename: K
authors.initials: K
authors.lastname: Sato
authors.forename: K
authors.initials: K
authors.lastname: Takamatsu
mesh_terms: D000328:Adult; D015444:Exercise; D013006:Growth Hormone / Q000097:blood / Q000378:metabolism*; D006801:Humans; D019344:Lactic Acid / Q000097:blood*; D008297:Male; D010806:Physical Education and Training / Q000379:methods*
chemical_list: D019344:Lactic Acid; D013006:Growth Hormone