The mounting occurrences of intense heat waves signal the advancement of climate change [1]. Projections indicate that a significant portion of the global population will endure potentially deadly heat for over 20 days annually by the century’s close [2].
Our response to extreme heat hinges on climate change and our adaptability, resilience and capacity to withstand rising temperatures. As experts in physical activity science and environmental physiology, we delve into the connection between an active lifestyle and improved heat tolerance [3].
How does the body combat heat? When exposed to heat, the body initiates several defense mechanisms. The first step toward minimizing heat exposure is to make conscious decisions, such as seeking cooler environments and reducing physical exertion.
If these tactics prove inadequate, involuntary physiological responses come into play [4]. Blood vessels dilate in the skin to increase blood flow, while sweat glands intensify sweat production. Factors influencing these reactions can significantly affect the body’s ability to counter heat effectively.
People who are vulnerable
While heat affects everyone, specific population segments are more susceptible, heightening their risk. Age, pre-existing health conditions like heart disease and diabetes, particular medications, obesity, cognitive and physical limitations and low cardiorespiratory fitness all contribute to reduced heat tolerance and greater vulnerability [5].
These conditions are linked to diminished heat dissipation capacity and physiological potential, exacerbating the strain on the body and elevating the risk of heat-related health issues.
What’s the role of physical activity?
Notably, adopting an active lifestyle can mitigate several risk factors for heat-related health problems [6]. Engaging in regular physical activity throughout life can bolster our ability to handle increasing temperatures by [7]:
- Promoting physiological adaptations that enhance heat dissipation and cardiovascular resilience.
- Countering the decline in fitness associated with obesity, chronic diseases and certain medications.
- Slowing the natural aging-related decrease in cardiovascular and thermoregulatory functions.
- Contributing to improved mental well-being, aiding coping during extreme heat episodes.
Physical activity could significantly enhance individual and community resilience to climate change impacts. However, it’s crucial to acknowledge that certain risk factors are not modifiable through activity, such as mental health conditions and limited access to cool spaces [8]. Moreover, some occupations involving moderate to intense physical exertion during heat episodes may increase susceptibility to heat-related health issues.
Preparing the next generation
Current trends in obesity and physical activity among youth are concerning. A steep rise in obesity rates in Canadian children and adolescents coupled with a widespread lack of adherence to exercise guidelines paints a disheartening picture [9].
Similar global patterns reflect diminishing cardiorespiratory and functional capacities among young people. With projections of rising heat exposure, this poses a significant public health concern [10].
Encouraging consistent physical activity and maintaining fitness from a young age could better prepare the upcoming generations to face these challenges head-on.
[1] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9025182/
[2] https://www.wri.org/insights/deforestation-heat-stress-tropics
[3] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10274554/
[4] https://www.ncbi.nlm.nih.gov/books/NBK507838/
[5] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3691706/
[6] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6888447/
[7] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7883311/
[8] https://theconversation.com/can-physical-activity-boost-our-resilience-to-rising-temperatures-209735
[9] https://pubmed.ncbi.nlm.nih.gov/15488429/
[10] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4240518/
