Physical activity and cardiometabolic health across an extreme lifestyle gradient

Cardiometabolic diseases commonly rise with market-integration, industrialization, and urbanization, yet the direct role of physical activity remains debated. We collected accelerometry, health, and interview data from 1075 Orang Asli adults in Peninsular Malaysia, who currently span a wide range from rural, non-industrial to urban, industrialized lifestyles. More urban lifestyles were associated with reduced physical activity and worse cardiometabolic health. However, physical activity mediated only a small portion of urbanization's effects, suggesting independent influences. Age-related declines in activity were steeper in urban settings, indicating that non-industrial lifestyles promote activity in old age and may buffer older adults from functional decline. These results support the view that declining physical activity is an evolutionarily novel challenge contributing to poor health in modern environments.