EXTREME AND DEADLY HEAT WAVES Part 2

WHAT ARE HEAT RELATED ILNESSES?

HOW TO PREVENT THEM?

Excess heat works against our body’s physiology. It triggers the body’s compensatory heat regulation mechanism to work hard and prevent our body from overheating.

If heat is too high, the body’s compensatory mechanism goes into overdrive with mechanisms including tachycardia (rapid heartbeats), profound perspiration and labored breathing to control excess heat and to cool the body. 

If this process continuous unabated, the following cascading events and heat related illnesses start to occur: Body’s core temperature starts to raise, profound sweating ensues, rapid dehydration with electrolytes imbalance occurs. The body loses a lot of fluid and electrolytes, especially sodium with profound perspiration.

Laborers and sporty people could lose 20 g of sodium a day, with heavy perspiration in very warm weather. Therefore, fluid and electrolytes loss must be replaced by frequently by drinking liquids to prevent dehydration. The preferred beverage should be, not plain water, but a sports drink that contains certain electrolytes. It should be remembered that thirst is a poor indicator of dehydration during exercise. Frequent fluid intake, without being thirsty is necessary to prevent dehydration.

With dehydration, blood pressure may drop a bit and respiratory alkalosis may follow and dizziness may occur. If these events ignored, it leads to more severe heat exhaustion which manifest itself with more dizziness, nausea, and muscle cramps and a cloudy mind. If these symptoms continue, it progresses to much more dangerous heatstroke, which manifests with headaches, vomiting and mental confusion. The heart starts to fail and can no longer pump enough blood to the periphery for cooling, the core body start to raise to dangerous levels, and if it heats more than 104 F or more, the body’s physiologic functions stop, the brain start to swell, and deep coma and death follows.

These late stages of heat related illnesses need professional hospital care with rapid internal and external cooling as soon as possible.

It is best to prevent heat related illnesses occurring in the first place. A group of exercise scientists have written a comprehensive scientific review about training and competing in the extreme heat, in preparation for Summer Olympics in Tokyo. Their recommendations apply to all of us:

1-     Use your common sense. When it’s very hot outside, do your exercises indoors, or do it very early in the mornings when outside temperature is lower.

2-     Drink ice-cold beverage (preferable sport drinks that contain some sodium and other electrolytes) about 25-30 minutes before exercising. If you drink just before exercise, it will cause stomach cramps.

3-     Aim for acclimatization of your body for working out in warm weather. Start with short sessions when the day is warmest and gradually prolong your work out time. This will get your body accustomed to cope better with excess heat more efficiently, without any uncomfortable symptoms.

4-     Take a quick (10- 20 minutes) warm shower after each acclimatization sessions. This hot shower will make you perspire more which helps your body to acclimatize better.

5-     Beware of the signs of overheating. If you feel dizzy, become nauseous or have muscle cramps immediately stop running, and go to a shaded area to rest and cool off. In is better not to run alone, in a very warm weather, because you might develop excessive heat induced mental fog and impaired judgement that prevents you to make a right decision about your condition.