To cool itself, the body sends extra blood circulating through the skin. This takes blood away from the muscles, which in turn increases heart rate. This trifecta of events leaves the body vulnerable to heat illness.
More: 10 Tips for Hot Summer Runs
Here's what to watch out for:
Heat Cramps
These are painful muscle contractions occurring mainly in the calves, quadriceps and abdominals.
Heat Exhaustion
When experiencing heat exhaustion, body temperatures can rise as high as 104 degrees. This includes the onset of symptoms such as nausea, vomiting, headache, fainting, dizzy spells, weakness, and clammy skin.
More: The Truth About Hydration in the Heat
Heat Stroke
When experiencing heat stroke, body temperatures can rise in excess of 104 degrees. The body will be hot to the touch, but perspiration will be non-existent. If left untreated, heat exhaustion can lead to organ failure, brain damage, and even death.
Athletic fatigue may involve weakness and nausea. Ultimately, the only way around any type of heat illness is preparation and avoidance.
More: 7 Ways to Beat the Summer Heat
Here's how to overcome the dangers of running in the heat:
1. Know what you are getting into.
Be aware of the temperature outside and adjust your workout if it is abnormally hot.
2. Hydrate.
Dehydration can easily lead to heat illness. If you are planning a hard workout, substitute a sports drink for water. The sports drink will be higher in sodium, chloride and potassium.
More: What You Need to Know About Runner Hydration
3. Dress for the weather.
Think lightweight and breathable. Stay away from dark colors and wear a hat.
4. Ease into it.
If it's the first hot day of the year, postpone your long run. Be smart, be patient and be healthy.
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