title: Adipocytokine and ghrelin levels in relation to bone mineral density in prepubertal rhythmic gymnasts entering puberty: a 3-year follow-up study.
abstract: OBJECTIVE
  To investigate changes in bone mineral density (BMD) in rhythmic gymnasts (RG) entering puberty and their age-matched untrained controls (UC) over the 36-month period, and associations with leptin, adiponectin and ghrelin over this period.
  
  
  METHODS
  Whole body (WB), lumbar spine (LS) and femoral neck (FN) BMD, WB bone mineral content (BMC), and leptin, adiponectin and ghrelin were measured in 35 RG and 33 UC girls at baseline and at 12-month intervals over the next 3 years. The change over the 36 months was calculated (∆ score).
  
  
  RESULTS
  The pubertal development over the next 36 months was slower in RG compard to UC, while there was no difference in bone age development between the groups. BMD at all sites was higher in RG in comparison with UC at every measurement point. ∆LS BMD and ∆FN BMD, but not ∆WB BMD and ∆WB BMC, were higher in RG compared with UC. None of the measured hormones at baseline or their ∆ scores correlated with ∆BMD and ∆BMC in RG. Baseline fat free mass correlated with ∆WB BMD and ∆WB BMC in RG, while baseline leptin was related to ∆WB BMC, ∆WB BMD and ∆LS BMD in UC.
  
  
  CONCLUSIONS
  Measured baseline hormones and their ∆ scores did not correlate with increases in bone mineral values in RG entering puberty. Although the pubertal development in RG was slower than in UC, high-intensity training appeared to increase BMD growth and counterbalance negative effects of slow pubertal develpment, lower fat mass and leptin in RG.
authors.affiliation: Institute of Sport Sciences and Physiotherapy, Faculty of Medicine, University of Tartu, 18. Ülikooli St., 50090, Tartu, Estonia.
authors.forename: Kristel
authors.initials: K
authors.lastname: Võsoberg
authors.affiliation: Department of Pediatrics, Faculty of Medicine, University of Tartu, Tartu, Estonia.
authors.forename: Vallo
authors.initials: V
authors.lastname: Tillmann
authors.affiliation: Tartu Health Care College, Tartu, Estonia.
authors.forename: Anna-Liisa
authors.initials: AL
authors.lastname: Tamm
authors.affiliation: Institute of Sport Sciences and Physiotherapy, Faculty of Medicine, University of Tartu, 18. Ülikooli St., 50090, Tartu, Estonia.
authors.forename: Toivo
authors.initials: T
authors.lastname: Jürimäe
authors.affiliation: Clinics of Traumatology and Orthopaedics, Faculty of Medicine, University of Tartu, Tartu, Estonia.
authors.forename: Katre
authors.initials: K
authors.lastname: Maasalu
authors.affiliation: Institute of Sport Sciences and Physiotherapy, Faculty of Medicine, University of Tartu, 18. Ülikooli St., 50090, Tartu, Estonia. jaak.jurimae@ut.ee.
authors.forename: Jaak
authors.initials: J
authors.lastname: Jürimäe
mesh_terms: D052242:Adiponectin / Q000097:blood*; D015519:Bone Density; D016022:Case-Control Studies; D002648:Child; D005260:Female; D054439:Ghrelin / Q000097:blood*; D006173:Gymnastics / Q000502:physiology*; D006801:Humans; D020738:Leptin / Q000097:blood; D011627:Puberty / Q000097:blood / Q000502:physiology*
chemical_list: D052242:Adiponectin; D054439:Ghrelin; D020738:Leptin
keywords: Blood biomarkers; Bone mineral density; Puberty; Rhythmic gymnasts