With July and August quickly approaching, and the hottest weather of the summer so far on our doorstep, summer heat waves are becoming a reality. Get ready to sweat profusely whether you are exercising or just walking to your parking spot from the office. When gearing up for your outside excursions this summer you should not only check the temperature, but also be aware of the amount of moisture in the air. The humidity can be a major player in your outdoor plans and could ruin your day if you don’t plan appropriately.

When our body temperatures starts to go up, humans have a natural cooling mechanism with sweat. When our sweat evaporates from our skin, the process requires energy to change from a liquid to a water vapor. Liquid obtains this energy by using up heat, or in our case, body heat. This allows us to naturally cool back down. With more moisture in the air however, the ability for water to evaporate becomes more difficult. The more moisture present, the harder it is to evaporate, which means in the case of the human body, we retain more heat than they would in dry air. This can be dangerous for conditioned athletes or the average human being. For example: A temperature of 90 degrees at 70% humidity would actually seem like 105 degrees!

This is why we use the heat index to derive the perceived temperature to our bodies. Heat Index is essentially the measurement of the air temperature and relative humidity to derive the “felt air temperature” or apparent temperature by our bodies.

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Knowing the heat index is especially important before exercising outside during the summer. Overheating can be life-threatening but if recognized in the early stages, heat related emergencies can usually be reversed.

Heat cramps, heat exhaustion, and heat stroke are the three main types of heat related illnesses. Some symptoms include:
Heat cramps: muscle spasm

Heat exhaustion: cool, most, pale, ashen or flushed skin, headache, nausea, weakness, exhaustion, dizziness, and heavy sweating.

Heat Stroke: red hot, dry skin, changes in level of consciousness and vomiting.

Make sure this summer to not exercise in hot and humid conditions and make sure to stay attentive to the Heat Index before spending long periods outside. If you have to be outside, be sure to drink plenty of water and take plenty of breaks in the shade to cool down. As said by author Caroline Schoeder, “Some people change their ways when they see the light; others when they feel the heat”.