title: [Practice of martial arts and bone mineral density in adolescents of both sexes].
abstract: OBJECTIVE
  The purpose of this study was to analyze the relationship between martial arts practice (judo, karate and kung-fu) and bone mineral density in adolescents.
  
  
  METHODS
  The study was composed of 138 (48 martial arts practitioners and 90 non-practitioners) adolescents of both sexes, with an average age of 12.6 years. Bone mineral density was measured using Dual-Energy X-ray Absorptiometry in arms, legs, spine, trunk, pelvis and total. Weekly training load and previous time of engagement in the sport modality were reported by the coach. Partial correlation tested the association between weekly training load and bone mineral density, controlled by sex, chronological age, previous practice and somatic maturation. Analysis of covariance was used to compare bone mineral density values according to control and martial arts groups, controlled by sex, chronological age, previous practice and somatic maturation. Significant relationships between bone mineral density and muscle mass were inserted into a multivariate model and the slopes of the models were compared using the Student t test (control versus martial art).
  
  
  RESULTS
  Adolescents engaged in judo practice presented higher values of bone mineral density than the control individuals (p-value=0.042; Medium Effect size [Eta-squared=0.063]), while the relationship between quantity of weekly training and bone mineral density was significant among adolescents engaged in judo (arms [r=0.308] and legs [r=0.223]) and kung-fu (arms [r=0.248] and spine [r=0.228]).
  
  
  CONCLUSIONS
  Different modalities of martial arts are related to higher bone mineral density in different body regions among adolescents.
authors.affiliation: Instituto de Biociências, Universidade Estadual Paulista Júlio de Mesquita Filho (Unesp), Rio Claro, SP, Brasil. Electronic address: igorhidekiito44@gmail.com.
authors.forename: Igor Hideki
authors.initials: IH
authors.lastname: Ito
authors.affiliation: Instituto de Biociências, Universidade Estadual Paulista Júlio de Mesquita Filho (Unesp), Rio Claro, SP, Brasil.
authors.forename: Alessandra Madia
authors.initials: AM
authors.lastname: Mantovani
authors.affiliation: Universidade Estadual Paulista Júlio de Mesquita Filho (Unesp), Presidente Prudente, SP, Brasil.
authors.forename: Ricardo Ribeiro
authors.initials: RR
authors.lastname: Agostinete
authors.affiliation: Universidade Estadual Paulista Júlio de Mesquita Filho (Unesp), Presidente Prudente, SP, Brasil.
authors.forename: Paulo
authors.initials: P
authors.lastname: Costa Junior
authors.affiliation: Universidade Estadual Paulista Júlio de Mesquita Filho (Unesp), Presidente Prudente, SP, Brasil.
authors.forename: Edner Fernando
authors.initials: EF
authors.lastname: Zanuto
authors.affiliation: Universidade Estadual Paulista Júlio de Mesquita Filho (Unesp), Presidente Prudente, SP, Brasil.
authors.forename: Diego Giulliano Destro
authors.initials: DG
authors.lastname: Christofaro
authors.affiliation: Universidade do Algarve, Faro, Portugal.
authors.forename: Luis Pedro
authors.initials: LP
authors.lastname: Ribeiro
authors.affiliation: Universidade Estadual Paulista Júlio de Mesquita Filho (Unesp), Presidente Prudente, SP, Brasil.
authors.forename: Rômulo Araújo
authors.initials: RA
authors.lastname: Fernandes
mesh_terms: D000293:Adolescent; D015519:Bone Density; D002648:Child; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D016139:Martial Arts / Q000502:physiology*
keywords: Adolescentes; Adolescents; Artes marciais; Bone mineral density; Densidade mineral óssea; Martial arts