Interactions between Sedentary and Physical Activity Patterns, Lean Mass, and Bone Density in Arab Men

The study examined the associations between physical activity and appendicular lean mass (ALM), fat mass, and bone mineral density (BMD) and examined the role of physical activity on these variables. The participants included 497 men (age: 32.2 ± 10.4 years and body mass index: 28.2 ± 5.4 kg/m²). The study was cross-sectional, and measurements included body composition measured on dual-energy X-ray absorptiometry and self-reported physical activity assessed using the International Physical Activity Questionnaire. Physical activity, including light physical activity, was associated with increased ALM (P ≤ 0.05). Fat indicators, including waist circumference, were positively associated with ALM (P ≤ 0.05), but not with BMD. Physical activity, including moderate-to-vigorous physical activity, was not associated with BMD, whereas ALM and handgrip strength were significantly associated with BMD (P ≤ 0.05). Physical activity independent of exercise intensity was directly associated with ALM and indirectly associated with BMD through increased muscle mass and strength.