The Impact of Illinois Climate Change and the Heat Index on Outdoor Athletes Over 40

When you hit the running trail and feel like the thermometer must be wrong – it’s got to be hotter than 73 out! – you’re not alone in this feeling. Rapid climate changes in Illinois have impacted the heat index.

Dr. Riana R Pryor, PhD, ATC at the University of Buffalo, says that “The heat index is a calculation that combines the air temperature and the relative humidity and can be thought of as the ‘feels like’ temperature…If you’re in a part of the world that is becoming hotter, this will increase the heat index…”

According to major scientific assessments led by The Nature Conservancy, Illinois has seen dramatic, rapid climate changes in the past decades. You may feel like the summers are hotter and muggier than they used to be. You’re not wrong.

Daniel J. Vecellio, postdoctoral research scholar at the Virginia Climate Center notes that “climate change is occurring, causing increases in the frequency, magnitude, and duration of heatwaves.” As the climate of Illinois changes, more heatwaves hit during the summers. Vecellio says, “This [increase] impacts those partaking in strenuous physical activity…For our bodies to maintain homeostasis…we need to dissipate the heat we [create] via our resting metabolism plus the heat our [bodies produce] through physical activity, as well as any we [gain] from the environment.”

Vecellio notes that a “A high heat index not only means it is hot outside, but typically also means there is a relative increase in humidity…High humidity causes a decrease in the efficiency of sweat doing its job in cooling the body because the sweat can’t be evaporated into the surrounding environment as easily.”

Additionally, folks over 40 have a harder time dealing with these climate changes. According to Dr. Pryor, “Starting around the age of 40 years old…runners will have higher body temperatures…even if they [have] the same fitness status and are running at the same intensity [as younger runners]. As the skin ages, it loses the ability to dissipate heat as easily via sweating…Older runners have a smaller capacity to maximally sweat, limiting their maximal ability to evaporate that sweat to cool down.”

Limiting the negative impact of climate change on your outdoor running is possible through specific prevention strategies. Dr. Pryor notes that the following precautions should be taken.

  1. When the warm season begins, acclimatize to the heat by easing into training with slow increases of duration and pace during the first two weeks.
  2. Run during the cooler parts of the day, when possible.
  3. Run on shaded, windy paths.
  4. Run in a hydrated state and rehydrate with frequent breaks on your run.
  5. Learn the symptoms of heat illnesses and listen to your body.