Heat, Environmental Factors, and Working Out

I have always liked working out outdoors. While I exercise indoors at the gym most of the time, during the weekend I like to go running and walking along a trail by the Bayamón River banks. The beautiful scenery and birds are part of what makes this workout something I look forward to the whole week. However a recent diagnosis of temporary high blood pressure prevented me from working out for a few weeks. Resuming exercise involved only working out indoors and eliminating all high intensity workouts. At first, I was reluctant to refrain from running outdoors. So I have resumed my runs at a slower pace and during the early morning hours.

While I am sunwise during outdoor activities and protect my skin from UV rays by wearing a wide baseball cap, sunscreen and sunglasses, I was not aware that other environmental factors can contribute to heart disease and aggravate high blood pressure. Excessive heat and poor air quality are the most common environmental culprits related to heart problems. Hot weather can worsen ground-level ozone and air quality. In Puerto Rico, during the summer, Sahara dust particles make the situation even worse. According to NOAA’s website, high temperature, humidity and physical exertion can lead to heat disorder or heat stress.

Heat stress occurs when the body can no longer keep blood flowing to supply vital organs nor send blood to the skin to reduce body temperature. Signs of heat exhaustion include:

  • weakness
  • headache
  • breathlessness
  • nausea or vomiting
  • feeling faint or actually fainting.

It takes 30 minutes at least to cool the body down once a person suffers heat exhaustion. If not treated promptly, heat exhaustion can lead to serious heart problems. Preventing heat stress is simple. Here are a few suggestions I am currently following in order to enjoy exercise in the great outdoors without putting my overall health at risk.

  • Take rest breaks–I pause for 5 minutes intervals during my 4-mile jog
  • Limit heat exposure time—Perform outdoor activities early in morning or late afternoon hours
  • Check the air quality index — Avoid exercising when air quality is poor
  • Wear light and loose-fitting clothing
  • Drink plenty of water

Simple steps will allow you to stay healthy while you exercise!

About the author: Brenda Reyes Tomassini joined EPA in 2002. She is a public affairs specialist in the San Juan, Puerto Rico office and also handles community relations for the Caribbean Environmental Protection Division.

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