Physical Performance Variables and Bone Mineral Density in a Group of Young Overweight and Obese Men.

The aim of this study was to explore the relationships between performances obtained in different physical tests and bone parameters (bone mineral density [BMD], bone mineral content, hip geometry indices, and trabecular bone score [TBS]) in a group of young Lebanese overweight and obese adult men. Fifty-two overweight and/or obese (body mass index > 25 kg/m2) young men whose ages range from 18 to 35 yr participated in this study. Weight and height were measured, and body mass index was calculated. Body composition, BMD, cross-sectional area and section modulus (Z) of the femoral neck (FN), and TBS were measured by dual-energy X-ray absorptiometry. Maximum oxygen consumption (VO2 max, in liter per minute) was determined by direct measurement while exercising on a medical treadmill. One-repetition-maximum half-squat and maximum power (P max) of the lower limbs were measured using validated exercises. Lean mass was a positive determinant of whole-body bone mineral content (r = 0.71, p < 0.001), FN cross-sectional area (r = 0.51, p < 0.001), and FN Z (r = 0.58, p < 0.001). VO2 max (in liter per minute) was a positive determinant of whole-body BMD (r = 0.47, p < 0.001), total hip BMD (r = 0.43, p < 0.01), and FN BMD (r = 0.42, p < 0.01). VO2 max (in milliliter per minute per kilogram) was a positive determinant of TBS (r = 0.30, p < 0.05). One repetition maximum was a positive determinant of L1-L4 BMD (r = 0.33, p < 0.05). This study suggests that VO2 max (in liter per minute) is a positive determinant of BMD, and VO2 max (in milliliter per minute per kilogram) is a positive determinant of TBS in overweight and obese men.

Performance physique et densité minérale osseuse chez de jeunes adultes libanais.

Introduction: The aim of this study was to explore the relationships between performances obtained in different physical tests and bone parameters (bone mineral density (BMD) and bone mineral content (BMC)) in a group of young Lebanese adults. Methods: One hundred and six young Lebanese adults (45 women and 61 men) whose ages range from 17 to 34 years participated in this study. Weight and height were measured, and body mass index (BMI) was calculated. Daily calcium intake, daily protein intake and physical activity level (h/week) were evaluated using validated questionnaires. The level of physical performance was measured using several physical tests: vertical-jump test, standing long jump test, 3-jumptest, 5-jump-test and 1-RM half-squat. Body composition, bone mineral content (BMC) and BMD at whole body (WB), lumbar spine (L2-L4), total hip (TH) and femoral neck (FN) were measured by dual-energy X-ray absorptiometry (DXA). Results: In women, height, lean mass, 1- RM half-squat and performances obtained in three physical tests (vertical jump test, 5-jump-test and 1-RM halfsquat) were positively correlated to BMD and BMC. In men, lean mass and 1-RM half-squat were positively correlated to BMD and BMC. Conclusion: This study suggests that lean mass and maximum strength obtained in half-squat are positively correlated to BMD in young adults.

Relative importance of lean mass and fat mass on bone mineral density in a group of Lebanese elderly men.

METHODS AND RESULTS: Seventy Lebanese men (aged 65-84 years) participated in this study. Body weight and height were measured and body mass index (BMI) was calculated. Body composition (lean mass, fat mass and fat mass percentage) was assessed by dual-energy X-ray absorptiometry (DXA). Bone mineral content (BMC) of whole body (WB) and BMD of WB, total hip (TH), femoral neck (FN), ultra distal (UD) radius and 1/3 radius were measured by DXA. The ratios WB BMC/height and WB BMD/height were calculated. Fat mass and lean mass were found to be positively correlated to WB BMC, WB BMC/height, and to WB, TH, FN, UD radius and 1/3 radius BMD. After controlling for age and height, fat mass was more strongly correlated to TH BMD and FN BMD than lean mass while lean mass was more strongly correlated to WB BMC, WB BMD, UD radius BMD and 1/3 radius BMD than fat mass. CONCLUSION: This study suggests that, in elderly men, fat mass is a stronger determinant of TH and FN BMD than lean mass while lean mass is a stronger determinant of WB BMC, WB BMD, UD radius BMD and 1/3 radius BMD than fat mass.