title: Calcaneal Bone Mass Modification in Recreational Runners.
abstract: BACKGROUND
  The calcaneus is the bone of the foot that first receives the impact of running, generating vibrations that might have a positive effect in modifying the trabecular bone mass. The objective of this study was to determine the variation in calcaneal bone density in runners during a 6-month training season, comparing it with a control sample.
  
  
  METHODS
  Bone density of the heel was measured in 33 male recreational runners by means of a contact ultrasonic bone analyzer. Measurements were made on three occasions during a training season: at the beginning, at 350 km, and at 700 km. All of the runners wore the same model of running shoes during this period. Measurements of bone density were also made in a control sample of 62 men who did not engage in physical exercise.
  
  
  RESULTS
  There was a significant decrease in mean calcaneal bone density over the course of the training season (from 86.1 dB/MHz to 83.2 dB/MHz; P = .006), but no significant differences with the control sample value (from 80.7 dB/MHz to 81.1 dB/MHz; P = .314). The runners' body composition changed during the study period, with lean mass increasing and fat mass decreasing.
  
  
  CONCLUSIONS
  Distance running seems to have a negative effect on calcaneal bone mass density during the course of a 700-km training season.
authors.forename: Elena
authors.initials: E
authors.lastname: Escamilla-Martínez
authors.forename: Alfonso
authors.initials: A
authors.lastname: Martínez-Nova
authors.forename: Beatriz
authors.initials: B
authors.lastname: Gómez-Martín
authors.forename: Raquel
authors.initials: R
authors.lastname: Sánchez-Rodríguez
authors.forename: Lourdes María
authors.initials: LM
authors.lastname: Fernández-Seguín
authors.forename: Juan Diego
authors.initials: JD
authors.lastname: Pedrera-Zamorano
mesh_terms: D000328:Adult; D000367:Age Factors; D000886:Anthropometry; D001835:Body Weight; D015519:Bone Density; D002111:Calcaneus / Q000000981:diagnostic imaging*; D016022:Case-Control Studies; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D011998:Recreation; D012016:Reference Values; D018570:Risk Assessment; D012420:Running / Q000502:physiology*; D014463:Ultrasonography / Q000379:methods