Climate change is reducing human physical activity, creating long-term burdens on health and the broader economy, according to a new study. Rising temperatures could lead to hundreds of thousands of premature deaths and billions of dollars in productivity losses as people move less, researchers found.
An international research team from Pontifical Catholic University of Argentina (UCA), including researcher Cristián García-Witulski, analyzed how temperature increases from climate change could reduce physical activity among adults worldwide by 2050, potentially causing hundreds of thousands of premature deaths and billions of dollars in productivity losses. The findings were published on May 17 in The Lancet Global Health.
The researchers modeled how rising temperatures would affect global physical activity through 2050, using data from 156 countries collected between 2000 and 2022. The analysis predicted that global physical inactivity rates would increase by 1.5 percentage points for each additional month when average temperatures exceed 27.8 degrees Celsius.
The impacts varied by country. Physical inactivity rates were projected to rise by 1.85 percentage points in low- and middle-income countries, while high-income countries showed no significant change. Regionally, already-hot areas such as Central America and the Caribbean, East sub-Saharan Africa, and equatorial Southeast Asia were expected to experience greater impacts. The researchers estimated that physical inactivity rates in these regions could increase by more than 4 percentage points for each additional month exceeding 27.8 degrees Celsius.
The health and economic repercussions are substantial. The researchers estimated that reduced physical activity from climate change could lead to 470,000 to 700,000 additional premature deaths annually worldwide. Associated productivity losses were projected to reach $2.4 billion to $3.68 billion. This suggests the climate crisis could disrupt not only workplaces but also daily lifestyle habits and health management practices.
The study is notable for broadening perspectives on climate change's health impacts. Previous discussions have primarily focused on physical harms such as direct deaths from heat waves and reduced labor productivity. This paper is significant for quantifying indirect pathways through which rising temperatures reduce outdoor activity and increase risks of insufficient exercise and chronic diseases.
"This study is meaningful in showing a new pathway through which global warming affects human behavior and health, beyond simply raising average temperatures or increasing extreme weather events," said Kug Jong-seong, a professor in the School of Earth and Environmental Sciences at Seoul National University. "It quantitatively demonstrates, by combining global data with climate model scenarios, that outdoor activity decreases and physical inactivity increases when temperatures rise above certain threshold levels."
Professor Kug noted that the study highlights climate inequality issues. "This suggests that climate change impacts can lead to long-term health burdens through behavioral changes and increased chronic diseases, not just direct harms like heat wave deaths or reduced labor productivity," he said. "Given that impacts appear greater in tropical and low-latitude regions, integrated Earth system research incorporating human activity and health will become increasingly important."