title: Muscle strength, power and cardiorespiratory fitness are associated with bone mineral density in men aged 31-60 years.
abstract: BACKGROUND
  Osteoporotic fractures represent a growing economical burden to society, not only because of fractures in women, but also because of an increasing number of fractures in men.
  
  
  OBJECTIVE
  In this cross-sectional study we aimed to investigate the association of muscular and cardio-respiratory fitness with BMD at the spine and hip in men.
  
  
  RESULTS
  The association between independent variables maximal aerobic capacity (VO(2max)), leg power and hand grip strength, and dependent variables BMD at the spine and total hip was explored in a series of linear regression models successively adjusted for age, weight and height, smoking, alcohol intake and leisure time physical activity level. In the fully adjusted model we found a significant association of VO(2max) with BMD at the lumbar spine, p<0.0089. Furthermore, we observed significant associations of VO(2max) (p<0.0022) and leg power (p<0.011) with BMD at total hip.
  
  
  CONCLUSIONS
  We found that cardiorespiratory fitness was associated with BMD in men. Furthermore, hand grip strength and leg power were associated with increasing BMD at the lumbar spine and total hip in men, respectively. Further prospective studies are needed to further investigate the association between physical activity and BMD in men.
authors.affiliation: Research Centre of Ageing and Osteoporosis, Department of Medicine, Copenhagen University Hospital, Glostrup, Denmark Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark peter.schwarz@regionh.dk.
authors.forename: Peter
authors.initials: P
authors.lastname: Schwarz
authors.affiliation: Department of Diagnostics, Copenhagen University Hospital, Glostrup, Denmark.
authors.forename: Niklas
authors.initials: N
authors.lastname: Jørgensen
authors.affiliation: Research Centre of Ageing and Osteoporosis, Department of Medicine, Copenhagen University Hospital, Glostrup, Denmark.
authors.forename: Barbara
authors.initials: B
authors.lastname: Nielsen
authors.affiliation: Research Centre for Prevention and Health, Capital Region of Denmark, Glostrup, Denmark.
authors.forename: Anne Sofie
authors.initials: AS
authors.lastname: Laursen
authors.affiliation: Research Centre for Prevention and Health, Capital Region of Denmark, Glostrup, Denmark.
authors.forename: Allan
authors.initials: A
authors.lastname: Linneberg
authors.affiliation: Research Centre for Prevention and Health, Capital Region of Denmark, Glostrup, Denmark.
authors.forename: Mette
authors.initials: M
authors.lastname: Aadahl
mesh_terms: D000328:Adult; D015519:Bone Density / Q000502:physiology*; D003430:Cross-Sectional Studies; D018737:Hand Strength / Q000502:physiology*; D006615:Hip / Q000502:physiology; D006801:Humans; D007866:Leg / Q000502:physiology*; D008159:Lumbar Vertebrae / Q000502:physiology; D008297:Male; D008875:Middle Aged; D010809:Physical Fitness / Q000502:physiology*; D013131:Spine / Q000502:physiology
keywords: BMD; Handgrip strength; bone; fitness; leg power