PHYSICAL-ACTIVITY AND BONE-MINERAL DENSITY IN ITALIAN MIDDLE-AGED WOMEN

Osteoporosis is a major health issue in postmenopausal women on accoun t of the association between low bone mineral density and fractures. A role of physical activity in the prevention and treatment of low bone mineral density is possible but still unclear. The relationship betwe en low spine bone mineral density measured by means of dual photon abs orptiometry at lumbar spines, and levels of past and recent physical a ctivity has been assessed by means of a population-based screening stu dy carried out on 1373 women (age 40-64 years) in the North-East of It aly. Physical activity at work and in leisure time was investigated fo r three specific periods of life: at age 12, between 15 and 19 years ( during bone formative years), and in the recent years prior to the int erview (30-39 or 50-59 years). Data were analysed comparing low versus high bone mineral density tertile (i.e., 458 and 461 women, respectiv ely), after controlling for other known contributory factors in the de velopment of osteoporosis. A positive association emerged with leisure time physical activity, with significant trends at age 15-19 (odds ra tio (OR) for low versus high tertile of leisure time activity: 1.4, 95 % confidence interval (CI): 0.8-2.4) and at most recent age (OR: 1.7, 95% CI: 1.1-2.6). Risk trends with occupational physical activity were less clear and non-statistically significant. The present Southern Eu ropean cross-sectional study lends further support to the possibility that past and recent physical activity helps increasing bone mineral d ensity in middle-aged women. Although the most beneficial type and int ensity level of exercise has yet to be determined, the present results provide further evidence that participation in even moderate exercise programs should be encouraged.