Exercise and Hot Weather
- Posted on: Jul 19 2017
When the temperature rises, we find it hard to perform the activities that were easier in the cooler months. Read further to find out more about exercise, warm weather and the potential risks associated with the heat.
The Physiology of Heat and the Human Body
When the temperature rises, so does your core body temperature. Your body responds with a natural cooling mechanism, which sends more blood to your skin. The increase in blood flow allows for increased fluid loss, which is seen as perspiration. This natural reaction reduces the amount of blood available to feed muscles, which increases your heart rate.
What Happens When There is Too Much Heat?
When temperatures get too high, your body responds with excess sweating and as a result there is a fluid deficit. This fluid deficit leads to heat related illnesses.
Heat Related Illnesses
Heat cramps are muscle contractions that occur due to dehydration. This can occur with or without a core body temperature increase.
This is a feeling of lightheadedness followed by fainting that is caused by increased air and core body temperatures. Collapse can occur with or without exercise and can be associated with standing after sitting for a long period of time.
Heat exhaustion is characterized by a body temperature less than or equal to 104 degrees F. Symptoms include nausea, vomiting, headache, syncope, sweating and cold clammy skin.
Heat stroke is an emergent condition that begins when the body temperature is greater than 104 degrees F. Symptoms include the symptoms of heat exhaustion accompanied with dry skin, visual disturbance, and fatigue. Heat stroke can lead to brain damage, organ failure, and death.
What to do if You Are Symptomatic?
If you notice signs and symptoms of heat related illness you must take action to reduce your core body temperature. Reduction in core body temperature can occur with a cold towel and ice packs, removal of extra clothing and fans. If you feel symptoms of heat exhaustion you should drink fluids (e.g. water or a sports drink). If you do not feel better within 20 minutes of heat exhaustion symptoms or feel symptoms associated with heat stroke call emergency medical assistance immediately.
Do not exercise outside during heat alerts.
Allow yourself 1-2 weeks to acclimate to the warmer weather. If you consistently perform exercise indoors, reduce the intensity and duration of your exercise outside until you are accustomed to the warmer temperatures.
Drink water or sports drinks to cool down the exercising body. When performing high intensity activity, drink sports drinks to replace electrolytes lost through sweating.
Wear lighter loose clothing to allow the body to cool. Avoid dark colors, which absorb sunlight.
Avoid exercise mid-day due to increased temperatures.
Protect your skin from the sun as sun burn increases fluid loss and skin cancer risk.
Be Careful and Get Moving with Caution this Summer!
By: Mary McCoy PT, DPT