News release

From: The Lancet

Modelling suggests climate change could drive millions globally into physical inactivity by 2050 and be linked to an estimated half a million premature deaths

Rising temperatures due to climate change could drive millions more adults globally into physical inactivity by 2050, being linked to hundreds of thousands of premature deaths and billions of dollars in lost productivity, suggests a modelling study published in The Lancet Global Health journal.

Climate change is making the world hotter, and this growing heat is likely to affect how active people can be. Physical inactivity is already a major global health problem, with about one in three adults failing to meet World Health Organization guidelines for weekly exercise [1].

This current study analysed data from 156 countries between 2000 and 2022 to model how rising temperatures may affect physical activity globally up to the year 2050. The model suggests that by 2050 each additional month with an average temperature above 27.8°C would increase physical inactivity by 1.5 percentage points globally and by 1.85 percentage points in low- and middle-income countries, but with no clear impact in high-income countries. This translates to a predicted 0.47–0.70 million additional premature deaths annually and US$ 2.40–3.68 billion in productivity losses.

The model predicts the biggest increase in inactivity to be hotter regions such as Central America, the Caribbean, Eastern Sub-Saharan Africa, and Equatorial Southeast Asia, where inactivity could rise by more than 4 percentage points per month spent above 27.8°C. However, the authors highlight that these are modelled projections, based on self-reported activity surveys and also only account for temperature changes, and so there remains major uncertainty as to the exact real-world impacts.

The authors say their results suggest that action is needed to protect public health from rising heat, including designing cooler cities, providing affordable air-conditioned places to exercise, and giving clear advice on how to stay safe in extreme heat, as we all as reducing greenhouse gas emissions.