title: Serum 25-hydroxyvitamin D is related to indicators of overall physical fitness in healthy postmenopausal women.
abstract: OBJECTIVE
  Inadequate vitamin D status is related to increased adiposity, risk of falls, and muscle weakness, particularly in older people. We hypothesized that serum 25-hydroxyvitamin D [25(OH)D] is related to physical fitness indices (androidal fat, whole body lean mass, balance, strength) in healthy postmenopausal women.
  
  
  METHODS
  Covariates for fitness indices included age or years since menopause, weight, 25(OH)D, energy expenditure, and calcium intake. Overall and regional (androidal fat mass = waist + hip fat) body composition was assessed (N = 242) via dual-energy x-ray absorptiometry.
  
  
  RESULTS
  Regression analyses revealed that 71% of variability (P <or= 0.0001) in androidal fat mass was accounted for by weight (53.0%, P <or= 0.0001), white blood cell (WBC) count (2.0%, P <or= 0.0001), supplemental calcium (1.7%, P = 0.0004), years since menopause (1.1%, P = 0.0034), 25(OH)D (1.0%, P = 0.0051), and vegetable servings (0.6%, P = 0.027); 64% of variability (P <or= 0.0001) in lean mass was accounted for by weight (63.1.%, P <or= 0.0001), WBC count (1.4%, P = 0.0038), and 25(OH)D (1.0%, P = 0.013); 12% of variability (P <or= 0.0001) in balance (right + left leg) was accounted for by age (3.8%, P = 0.0019), 25(OH)D (2.0%, P = 0.025), and WBC count (1.8%, P = 0.032); 14% of variability (P <or= 0.0001) in handgrip strength (right + left) was accounted for by weight (9.3%, P <or= 0.0001), 25(OH)D (2.4%, P = 0.013), WBC count (2.1%, P = 0.019), and age (1.6%, P = 0.044); and 22% of variability (P <or= 0.0001) in torso strength was accounted for by site (15.0%, P <or= 0.0001) and weight (4.6%, P = 0.0003).
  
  
  CONCLUSIONS
  Serum 25(OH)D was the common contributor to physical fitness indices (androidal fat mass, lean mass, balance, handgrip strength) in healthy postmenopausal women.
authors.affiliation: Department of Food Science and Human Nutrition, Iowa State University, Ames, IA 50010-8281, USA.
authors.forename: Jeanne W
authors.initials: JW
authors.lastname: Stewart
authors.forename: D Lee
authors.initials: DL
authors.lastname: Alekel
authors.forename: Laura M
authors.initials: LM
authors.lastname: Ritland
authors.forename: Marta
authors.initials: M
authors.lastname: Van Loan
authors.forename: Erik
authors.initials: E
authors.lastname: Gertz
authors.forename: Ulrike
authors.initials: U
authors.lastname: Genschel
mesh_terms: D000368:Aged; D001823:Body Composition; D015992:Body Mass Index; D049628:Body Size; D001835:Body Weight; D015519:Bone Density; D003430:Cross-Sectional Studies; D004311:Double-Blind Method; D005260:Female; D018737:Hand Strength; D006801:Humans; D007958:Leukocyte Count; D008137:Longitudinal Studies; D008875:Middle Aged; D010809:Physical Fitness / Q000502:physiology*; D010919:Placebos; D017698:Postmenopause / Q000097:blood*; D012044:Regression Analysis; D012621:Seasons; D011795:Surveys and Questionnaires; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood; D014808:Vitamin D Deficiency / Q000503:physiopathology
chemical_list: D010919:Placebos; D014807:Vitamin D; C104450:25-hydroxyvitamin D