Climate Action

Here's how physical activity can improve your resilience to heat

Regular physical activity can help to improve our resilience to heat by increasing our sweat production and cardiovascular reserve.

The number of days of extreme heat is set to increase in the years ahead. An active lifestyle can help reduce the impact on our health. Image: Pexels/Taryn Elliott

Thomas Deshayes
Postdoctoral Researcher in Physical Activity Sciences, University of Montreal
Julien Periard
Research Professor, University of Canberra
  • Climate change is causing longer, more frequent and more intense heatwaves.
  • Physical activity can help to limit the decline in cardiorespiratory fitness associated with ageing.
  • It is important to be aware of the signs and symptoms of heat-related illness and to take steps to cool down if you start to feel unwell.

Climate change, a high prevalence of chronic diseases and alarming levels of physical inactivity are three of the central challenges we face in the 21st century.

The increased frequency, duration and intensity of heat waves is one of the undeniable signs that climate change is well underway. According to the various climate scenarios, by the end of the century between half and three-quarters of the world’s population will be exposed to lethal heat for more than 20 days per year.

The future impact of extreme heat events will depend on the extent of climate change, but also on our ability to adapt to it by becoming less sensitive and vulnerable to heat, and therefore more resilient. As researchers in physical activity science and environmental physiology, we are assessing how adopting an active lifestyle can make us better equipped to cope with rising global temperatures.

Discover

What’s the World Economic Forum doing about climate change?

How can the human body combat heat?

A child enjoys water jets in Montréal during a heat wave.
A child enjoys water jets in Montréal during a heatwave. Image: Shutterstock

When exposed to heat, the body deploys several responses to try to dissipate it. The first is conscious and depends on behavioural decisions we make to minimize exposure, such as seeking a cool place, switching on a fan or reducing our physical activity.

Secondly, if these strategies are not sufficient, the brain activates physiological responses that are beyond our control; blood vessels in the skin dilate to increase the blood supply and sweat glands increase their activity to excrete more sweat.

So it’s not surprising that any factor that affects these responses can alter the body’s ability to react adequately to heat exposure.

Who are the most vulnerable groups?

A number of individual factors including age, pre-existing health problems such as cardiovascular disease and Type 2 diabetes, the use of certain medications (anticholinergic drugs, beta blockers, antidepressants and diuretics, among others), being overweight or obese, having low functional and cognitive abilities and low cardiorespiratory fitness are all associated with reduced heat tolerance and a greater risk of developing heat-related health problems. This is reflected in public health figures since these factors are associated with an increased risk of hospitalization or death during an extreme heat event.

This finding can be explained by the fact that several of these conditions are associated with two physiological responses:

  • reduced voluntary and autonomous heat dissipation capacities, which increase the stress imposed on the body;
  • reduced physiological potential, which reduces the body’s ability to cope.

Together, these two conditions increase the likelihood that the stress placed on the body will reach and exceed the body’s physiological potential, increasing the risk of developing heat-related health problems.

How can regular physical activity improve resilience to heat?

Regular physical activity can help to improve our resilience to heat by increasing our sweat production and cardiovascular reserve.
Regular physical activity can help by increasing our cardiovascular reserve. Image: BioRender.com

Interestingly, of the many risk factors for developing heat-related health problems, several can be avoided by adopting a healthy, active lifestyle. In fact, doing regular physical activity throughout one’s life could mean being better equipped to cope with rising global temperatures:

1. By bringing about a number of physiological adaptations that increase heat dissipation capacity (increased sweat production) and the body’s physiological potential (increased cardiovascular reserve), thereby increasing heat tolerance and helping to meet the increased demands placed on the cardiovascular system during heat stress;

2. By limiting the decline in cardiorespiratory fitness and thermoregulatory functions associated with obesity, chronic disease and the use of certain medications. Regular physical activity can also help to limit cognitive and functional decline, enabling people to maintain their independence, an important protective factor against heat;

3. By slowing the decline in cardiovascular function and thermoregulatory functions inherent in aging;

4. By contributing to improved mental well-being, which could help people cope with the stress associated with extreme heat episodes.

Physical activity could therefore make an important contribution to our ability to adapt to rising global temperatures, increasing our individual and community resilience.

However, it is important to note that a number of other risk factors are not directly modifiable by a healthy and active lifestyle, including certain mental health disorders, low socio-economic status and limited access to cool or air-conditioned places, among others. It is also well established that people who engage in intense to moderate physical activity during heat episodes are at greater risk of developing heat-related health problems (agricultural workers, construction workers, restaurant workers, etc.).

Have you read?

Is the next generation sufficiently equipped to meet this challenge?

Younger generations are less active than those who came before them. They risk being more vulnerable to extreme heat.
Younger generations are less active than those who came before them. They risk being more vulnerable to extreme heat. Image: Shutterstock

In Québec, recent figures paint a picture that is more than alarming: a 15 per cent decrease in cardiorespiratory capacity and a 30 per cent decrease in functional capacity in young people compared with their elders who underwent the same tests in the 1980s. Worse still, the researchers observed that among 15- to 17-year-olds, six out of 10 boys and seven out of 10 girls have a cardiorespiratory capacity that will expose them to cardiometabolic health problems in the future.

Such trends suggest that today’s young people may be less and less equipped to tolerate heat, while they will be increasingly exposed to it. From a public health point of view, this is alarming. Maintaining regular physical activity and adequate fitness throughout their lives could make young people better equipped to meet these challenges.

Don't miss any update on this topic

Create a free account and access your personalized content collection with our latest publications and analyses.

Sign up for free

License and Republishing

World Economic Forum articles may be republished in accordance with the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International Public License, and in accordance with our Terms of Use.

The views expressed in this article are those of the author alone and not the World Economic Forum.

Stay up to date:

Climate Crisis

Related topics:
Climate ActionHealth and Healthcare SystemsNature and Biodiversity
Share:
The Big Picture
Explore and monitor how Climate Crisis is affecting economies, industries and global issues
A hand holding a looking glass by a lake
Crowdsource Innovation
Get involved with our crowdsourced digital platform to deliver impact at scale
World Economic Forum logo
Global Agenda

The Agenda Weekly

A weekly update of the most important issues driving the global agenda

Subscribe today

You can unsubscribe at any time using the link in our emails. For more details, review our privacy policy.

The 3 climate priorities humanitarians need to boost their impact

Jagan Chapagain

December 12, 2024

Climate risks are set to slash corporate earnings. Here’s what CEOs and boards can do

About us

Engage with us

  • Sign in
  • Partner with us
  • Become a member
  • Sign up for our press releases
  • Subscribe to our newsletters
  • Contact us

Quick links

Language editions

Privacy Policy & Terms of Service

Sitemap

© 2024 World Economic Forum