لینک دانلود و خرید پایین توضیحات دسته بندی : وورد نوع فایل : .doc ( قابل ویرایش و آماده پرینت ) تعداد صفحه : 15 صفحه قسمتی از متن .doc : Physical Activity and Bone Measures in Young Children Received Aug 14, 2000; accepted Nov 20, 2000. Objectives. Physical activity has a beneficial effect on bone development in circumpubertal children, although its effect on younger children is uncertain. In this cross-sectional study, we examined associations between physical activity and bone measures in 368 preschool children (mean age: 5.2 years, range: 4-6 years). Design. Physical activity was measured using 4-day accelerometry readings, parental report of children's usual physical activity, and parental report of children's hours of daily television viewing. Total body and site-specific bone mineral content and area bone mineral density (BMD) were measured by dual energy radiograph absorptiometry. Results. After adju ...