Reduced physical activity due to global heating will lead to rise in health issues, study says | Climate crisis
Rising temperatures make physical activity undesirable or even dangerous in many parts of the world, and as global warming worsens it will further affect people’s ability to move.
Researchers analyzed data from 156 countries between 2000 and 2022 and modeled how rising temperatures could affect physical activity globally by 2050.
They found that each additional month with an average temperature above 27.8°C would increase physical inactivity by 1.5 percentage points on average globally, with an even higher increase of 1.85 points in low- and middle-income countries.
Physical inactivity increases the risk of cardiovascular disease, type 2 diabetes, certain cancers and mental health disorders, all of which shorten life expectancy, said the study’s lead author, Christian García-Witulski, a researcher at Lancet Countdown Latin America and a professor at the Pontifical Catholic University of Argentina.
Reduced physical activity is already a major global health problem and is responsible for around 5% of all adult deaths, according to the study published in the journal Lancet Global Health. About a third of the world’s population does not meet the World Health Organization’s guidelines for weekly exercise.
The study projects that increased physical inactivity could contribute to about half a million additional premature deaths per year and $2.4 billion to $3.68 billion in productivity losses by 2050.
The largest increases in inactivity are expected to occur in warmer regions such as Central America, the Caribbean, eastern sub-Saharan Africa and equatorial Southeast Asia, where inactivity could increase by more than four percentage points per month.
“It’s not just a climate story, it’s also an inequality story. The places expected to face the largest increases in climate-related inactivity are often the same ones with fewer resources to adapt,” García-Witulski said.
“In environments where people have less access to cooling, fewer safe indoor alternatives, and less flexibility in their daily schedules, heat appears more likely to translate into reduced physical activity.”
The model also predicts a greater increase in inactivity among women, which could reflect physiological differences as well as social factors, such as less time and access to cool places to exercise, García-Witulski said.
The results are model projections based on self-reported activity surveys and do not take into account other climate impacts such as extreme precipitation, flooding and tropical cyclones.
The authors say the findings show that physical activity should be treated as a climate-sensitive public health issue, not just an individual lifestyle choice.
“Staying active in a warming world depends not only on personal motivation, but also on urban design, infrastructure and access to reliable information. In practical terms, climate-resilient physical activity policies are those that help people stay active safely, even in warmer conditions,” García-Witulski said.
This means designing cooler cities by expanding tree cover and shade networks in streets and parks, providing affordable, air-conditioned places to exercise, and providing clear advice on how to stay safe in extreme heat, as well as ambitious emissions reductions.
