Serum 25-hydroxyvitamin D is related to indicators of overall physical fitness in healthy postmenopausal women.
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.
Stewart
Jeanne W
JW
Department of Food Science and Human Nutrition, Iowa State University, Ames, IA 50010-8281, USA.
Alekel
D Lee
DL
Ritland
Laura M
LM
Van Loan
Marta
M
Gertz
Erik
E
Genschel
Ulrike
U
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
D010919:Placebos; D014807:Vitamin D; C104450:25-hydroxyvitamin D