Relationships among Physical Activity Bone Mineral Density and Body Composition in Obese and Athletes.

Background: Osteoporosis is a significant global public health issue, increasingly affecting younger individuals and placing substantial economic burdens on society. Risk factors vary, with non-modifiable ones like age and ethnicity, as well as modifiable factors including corticosteroid use, caffeine intake, and reduced exercise. This study examines the relationship between bone density, body components, and physical activity (PA) in enhancing bone health, particularly in obese athletes.

Methods: The 66 participants aged 18 to 30 were classified into two groups: 34 obese and 32 athletes. Measured parameters included body composition through bioelectrical impedance analysis, and bone mineral density (BMD) via quantitative ultrasound, while PA was assessed using the International PA Questionnaire.

Results: Our findings revealed a significant positive correlation between BMD and PA (r=0.284, P=0.023). Additionally, PA demonstrated strong negative correlations with body mass index (BMI), fat mass, and visceral fat (r=-0.738, r=-0.733, and r=-0.704 respectively, all P<0.001). In contrast, no significant correlation was observed between PA and lean mass (r=0.065, P=0.609). BMD was negatively associated with BMI and visceral fat, while a robust correlation between basal metabolic rate and lean mass was evident.

Conclusions: A study comparing athletes involved in high-impact sports indicated that these athletes maintained adequate BMD for their chronological age (Z-score≥-2.0). Moreover, a significant difference in BMD was observed when comparing the athletes to the obese group(P=0.018).