Accession Number : ADA327713

Title :   The Effects of Calcium Intake and Physical Activity on the Bone Mineral Content and Bone Mineral Density of the United States Naval Academy Midshipmen.

Descriptive Note : Master's thesis,

Corporate Author : AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH

Personal Author(s) : Ogawa, Angela M.

PDF Url : ADA327713

Report Date : JUL 1997

Pagination or Media Count : 118

Abstract : Prevention of osteoporosis depends upon the identification of lifestyle factors that increase peak bone mass. We investigated the effects of calcium intake, weight bearing exercise (WBE), and strength training (ST) on total bone mineral content (TBMC) and bone mineral density (BMD) in 22 female and 13 male United States Naval Academy Midshipmen (MIDN). Each received 4 dual energy x-ray absorptiometry scans to measure TBMC and spine and hip BMD during the 2.8 year study period. Calcium intake was estimated at baseline and follow-up using a food frequency questionnaire. Frequency of WBE was determined at each visit using a questionnaire. The female's TBMC was predicted by calcium intake at baseline (p<.01) and increased during the study (p<.001) as did spine BMD. At follow-up calcium was a significant variable in a model predicting TBMC (p<.001), but was weaker than at baseline and not independent of body weight. In the male subjects, TBMC and spine BMD increased significantly (p<.005), (p<.05). Hip BMD did not increase in males or females. WBE was predictive of TBMC (p<.01), in female subjects weighing greater than 60 kg. This suggests that a threshold level of weight bearing (from body weight and exercise) is necessary to stimulate osteogenesis. We conclude that bone accretion occurs early in the third decade in MIDN and is highly influenced by body weight. Calcium intake and WBE in female MIDN may positively modify peak bone mass, although these effects were not independent of body weight.

Descriptors :   *CALCIUM, *SPINAL COLUMN, *BONES, *OSTEOGENESIS, *OSTEOPOROSIS, SCANNING, FREQUENCY, DENSITY, MEASUREMENT, PEAK VALUES, PHYSICAL PROPERTIES, MASS, THRESHOLD EFFECTS, ESTIMATES, BASE LINES, WEIGHT, MALES, ACCUMULATION, FOOD, PREVENTION, QUESTIONNAIRES, MINERALS, BODY WEIGHT, FEMALES, ORAL DOSAGE.

Subject Categories : Biochemistry
      Anatomy and Physiology
      Medicine and Medical Research

Distribution Statement : APPROVED FOR PUBLIC RELEASE