Sitting still while the world gets sicker: Rethinking physical inactivity as a public health emergency.

Physical inactivity (PI) has emerged as a "forgotten pandemic" in global health. Over a quarter of adults worldwide fail to meet recommended physical activity (PA) levels, a proportion that has remained largely unchanged since 2001. This inactivity drives a rising non-communicable disease burden, deepens health inequities, and generates substantial economic costs. Yet preventive action and dedicated funding remain insufficient. Despite international frameworks and national PA plans, with nearly 75% of countries reporting relevant policies, implementation remains inconsistent and population-wide impact elusive. Global efforts are constrained by systemic policy blind spots. Health in All Policies, a governance approach that integrates health considerations into policy decisions across sectors such as urban planning and education, remains widely endorsed but rarely enacted, foreclosing opportunities for action. Viewed through an equity lens, existing strategies disproportionately benefit more advantaged populations, leaving underserved groups behind. These shortcomings are compounded by short political cycles and chronic underinvestment in prevention, which prioritize short-term political wins over long-term gains. A fundamental paradigm shift is required, from fragmented, individually focused initiatives towards a multilevel, systems-based approach that aligns global, national, and local action. PA must be reframed as a societal investment, rather than a lifestyle choice contingent on individual responsibility. Genuine population-level empowerment stems not from placing the burden on individuals, but from creating environments and policies that enable active living. We call on global health leaders to elevate PA promotion to the forefront of political agendas, supported by increased funding, long-term vision, rigorous implementation, and targeted interventions for underserved populations.