Contributions of exercise, body composition, and age to bone mineral density in premenopausal women

• Published in: Medicine and science in sports and exercise 1995-11, Vol.27 (11), p.1477-1485
• Main Authors: ALEKEL, L, CLASEY, J. L, FEHLING, P. C, WEIGEL, R. M, BOILEAU, R. A, ERDMAN, J. W, STILLMAN, R
• Format: Article
• Language: English
• Subjects: Adult; Biological and medical sciences; Body Composition - physiology; Bone Density; Cross-Sectional Studies; Dancing - physiology; Exercise - physiology; Female; Femur - physiology; Fundamental and applied biological sciences. Psychology; Humans; Lumbar Vertebrae - physiology; Premenopause; Space life sciences; Vertebrates: body movement. Posture. Locomotion. Flight. Swimming. Physical exercise. Rest. Sports; Walking - physiology
• ISSN: 0195-9131; 1530-0315
• DOI: 10.1249/00005768-199511000-00003

The purpose of this cross-sectional study were to determine whether exercisers have greater bone mineral density (BMD) than nonexercisers, whether aerobic dancers have greater BMD than walkers, and to determine the contributions of energy expenditure, body composition, and dietary factors to spine and femur BMD. Measurements were obtained on 93 eumenorrheic women (walkers N = 28; aerobic dancers, N = 34; nonexercisers, N = 31) ages 25-41 yr; lumbar spine and proximal femur BMD, body composition, physical activity, and nutrient intakes. Mean height, weight, and body mass index and median age and calcium intakes were similar for the three groups. Mean (+/- SD) values of the spine, total femur, and femoral neck BMD, respectively, were: walkers (1.092 (+/- 0.098), 0.947 g.cm-2), dancers (1.070 (+/- 0.124), 0.990 (+/- 0.104), 0.908 (+/- 0.106) g.cm-2), and nonexercisers (1.020 (+/- 0.112), 0.887 (+/- 0.073), 0.792 (+/- 0.089) g.cm-2) multiple regression analyses indicated that exercise contributed to spine (P = 0.018), total femur (P =0.012), and femoral neck (P < 0.0001) BMD, whereas type of exercise (aerobic dance vs walking) did not (P > 0.05). Total femoral BMD was influenced by exercise (P = 0.012) and energy expenditure (P = 0.023), while vertebral BMD was influenced by age (P = 0.0067), body weight (P = 0.017), and exercise (P = 0.018). These findings suggest that walking and aerobic dance exercise may provide physically active premenopausal women with greater lumbar and femoral BMD than sedentary females.