title: Do calcium and vitamin D intake influence the effect of cycling on bone mass through adolescence?
abstract: BACKGROUND
  Cycling has been associated with decreased bone mass during adolescence. Calcium (Ca) and vitamin D (VitD) intake are associated to bone mass and may be important confounders when studying bone mass.
  
  
  OBJECTIVE
  To clarify the effect that Ca and VitD may have on bone mass in adolescent cyclists.
  
  
  METHODS
  Bone mineral content (BMC) and density (BMD) of 39 male adolescents (20 cyclists) were measured. Ca and VitD intake were also registered. Different ANCOVA analyses were performed in order to evaluate the influence of Ca and VitD on BMC and BMD.
  
  
  RESULTS
  Cyclists showed lower values of BMC and BMD than controls at several sites and when adjusting by Ca, Wards triangle BMD appeared also to be lower in cyclists than controls.
  
  
  CONCLUSIONS
  Nutritional aspects might partially explain differences regarding bone mass in adolescent cyclists and should be taken into account in bone mass analysis as important confounders.
authors.affiliation: GENUD Growth, Exercise, Nutrition and Development Research Group, University of Zaragoza, Spain.
authors.forename: A
authors.initials: A
authors.lastname: Gómez-Bruton
authors.forename: A
authors.initials: A
authors.lastname: González-Agüero
authors.forename: H
authors.initials: H
authors.lastname: Olmedillas
authors.forename: A
authors.initials: A
authors.lastname: Gómez-Cabello
authors.forename: A
authors.initials: A
authors.lastname: Matute-Llorente
authors.forename: C
authors.initials: C
authors.lastname: Julián-Almárcegui
authors.forename: J A
authors.initials: JA
authors.lastname: Casajús
authors.forename: G
authors.initials: G
authors.lastname: Vicente-Rodríguez
mesh_terms: D015502:Absorptiometry, Photon; D000293:Adolescent; D000704:Analysis of Variance; D001642:Bicycling / Q000502:physiology*; D015519:Bone Density; D001842:Bone and Bones / Q000033:anatomy & histology* / Q000187:drug effects; D002136:Calcium, Dietary / Q000494:pharmacology*; D006801:Humans; D008297:Male; D009752:Nutritional Status; D014807:Vitamin D / Q000494:pharmacology*; D014815:Vitamins / Q000494:pharmacology*
chemical_list: D002136:Calcium, Dietary; D014815:Vitamins; D014807:Vitamin D