title: Effects of plyometric exercise session on markers of bone turnover in boys and young men.
abstract: BACKGROUND
  The acute exercise effects on bone markers in adults are unclear, while in children, there are no such data.
  
  
  OBJECTIVE
  To investigate the acute response of biochemical markers of bone turnover to a high-impact exercise session consisting of high-mechanical loading in boys and young men.
  
  
  METHODS
  Twelve boys (10.2 ± 0.4 years) and 14 men (22.0 ± 0.8 years) underwent a protocol of plyometric jumping exercises (total 144 jumps). Venous blood samples were collected pre-, 5 min, 1 and 24 h post-exercise, and analyzed for markers of bone formation and resorption: bone-specific alkaline phosphatase (bone ALP), osteoprotegerin (OPG), amino-terminal cross-linking telopeptide (NTx), and receptor activator of nuclear factor kappa beta ligand (RANKL).
  
  
  RESULTS
  Boys had higher resting bone ALP (111.9 ± 29.2 vs. 30.6 ± 11.2 µg/L, p < 0.05) and NTx levels (49.8 ± 13.2 vs. 21.7 ± 5.9 nM BCE, p < 0.05) than men but no group differences were observed in resting OPG or RANKL. Following exercise (24 h), bone ALP and NTx increased in both boys and men (bone ALP: 24.1 vs. 9.9%, respectively; NTx: 23.5 vs. -5%, respectively), although the group-by-time interaction was not statistically significant. OPG increased significantly (p < 0.05) in both groups (5.7 and 16.1 %, respectively).
  
  
  CONCLUSIONS
  Even one session of plyometric exercises appear to stimulate bone formation in boys and men, as reflected by the increase in bone ALP and OPG. The boys' response appears more pronounced than the men's, suggesting that during growth, cellular bone activities respond with greater magnitude to mechanical stimuli.
authors.affiliation: Department of Kinesiology, Centre for Bone and Muscle Health, Faculty of Applied Health Sciences, Brock University, 500 Glenridge Ave., St. Catharines, ON, L2S 3A1, Canada.
authors.forename: Kimberly
authors.initials: K
authors.lastname: Kish
authors.affiliation: Department of Kinesiology, Centre for Bone and Muscle Health, Faculty of Applied Health Sciences, Brock University, 500 Glenridge Ave., St. Catharines, ON, L2S 3A1, Canada.
authors.forename: Yasmeen
authors.initials: Y
authors.lastname: Mezil
authors.affiliation: Department of Kinesiology, Centre for Bone and Muscle Health, Faculty of Applied Health Sciences, Brock University, 500 Glenridge Ave., St. Catharines, ON, L2S 3A1, Canada.
authors.forename: Wendy E
authors.initials: WE
authors.lastname: Ward
authors.affiliation: Department of Kinesiology, Centre for Bone and Muscle Health, Faculty of Applied Health Sciences, Brock University, 500 Glenridge Ave., St. Catharines, ON, L2S 3A1, Canada.
authors.forename: Panagiota
authors.initials: P
authors.lastname: Klentrou
authors.affiliation: Department of Kinesiology, Centre for Bone and Muscle Health, Faculty of Applied Health Sciences, Brock University, 500 Glenridge Ave., St. Catharines, ON, L2S 3A1, Canada. bfalk@brocku.ca.
authors.forename: Bareket
authors.initials: B
authors.lastname: Falk
mesh_terms: D000469:Alkaline Phosphatase / Q000097:blood; D015415:Biomarkers / Q000097:blood; D001862:Bone Resorption / Q000097:blood; D002648:Child; D006801:Humans; D008297:Male; D010012:Osteogenesis; D053244:Osteoprotegerin / Q000097:blood; D010748:Phosphopeptides / Q000097:blood; D059385:Plyometric Exercise; D011347:Procollagen / Q000097:blood; D053245:RANK Ligand / Q000097:blood; D055815:Young Adult
chemical_list: D015415:Biomarkers; C062121:N-propeptide type I collagen; D053244:Osteoprotegerin; D010748:Phosphopeptides; D011347:Procollagen; D053245:RANK Ligand; D000469:Alkaline Phosphatase
keywords: Bone formation; Bone resorption; Children; Jumping; Mechanical loading