Wednesday, July 3rd 2019, 2:00 pm - Extreme heat days are an occasional fact of life in Canada, and should be taken seriously.
The lead-up to summer may have been stop-and-start for many, but enduring warmth is here to stay -- and, eventually, the chance of extreme heat events where daytime highs exceed 30°C for prolonged periods of time.
When it is that hideously hot, it's usually a good idea to treat the risks with respect, and take steps to protect yourself.
We've previously talked about five terrible things extreme cold does to humans. Now, here are five horrible effects of extreme heat.
YOUR BODY STARTS ACTING WEIRD
The human body has an internal temperature of around 37°oC, and it does NOT like it when that very specific figure wobbles in either direction.
Changes of as little as a single degree can cause your body’s delicate biochemistry to glitch in unpleasant ways.
WATCH: WE PUT A REPORTER IN 50°C HOT CAR. SEE WHAT HAPPENS
You’d think that prolonged exposure to heat and humidity would have straightforward effects (you’ll read more about heat exhaustion and heat stroke down below), but sometimes the resulting malfunctions can take some odd forms.
Ever had a muscle cramp on a really hot day, say, while doing some heavy lifting? There’s a good chance the temperature is to blame.
What’s happened is that you’ve sweated out a lot of water, but even if you’ve been drinking water to replace it, you’re not getting enough electrolytes. The resulting salt imbalance is what’s causing the cramps.
For people really not used to the heat, there’s a risk of heat edema. To avoid overheating, your body dilates your blood vessels to try radiate as much heat away from your system as possible, causing blood to pool in your ankles.
Even sweating can sometimes not go as it’s supposed to. If you develop tiny red spots on your skin, with a prickly sensation, that’s a heat rash, caused when your sweat pores become blocked.
And according to the U.S. Centres for Disease Control, if you are exposed to extreme heat for a prolonged period, you may stop sweating altogether, a step on the road to potentially fatal heat stroke.
Before you get there, however, the extreme heat will do some unpleasant things to your head as well.
YOUR BRAIN DOESN'T WORK RIGHT
In 2014, Canadian tennis pro Frank Dancevic had a rather unusual court invasion.
Frank Dancevic at the 2013 U.S. Open. Source: Wikimedia Commons/Alexisrael
Like the other players at the Australian Open in Melbourne, he was struggling through a set in record heat, which became so overwhelming he apparently started seeing comic book characters.
"I was dizzy from the middle of the first set and then I saw Snoopy and I thought, 'Wow Snoopy, that’s weird,'" Dancevic said, according to Slate Magazine. "I couldn’t keep my balance anymore and I leaned over the fence and when I woke up people were all around me."
Confusion and dizziness are common effects of too much exposure to extreme heat, thanks to increased blood flow to dilated blood vessels and fluid loss through sweating.
It’s a real hazard for workers who need to keep their concentration in such conditions. The Canadian Centre for Occupational Health and Safety (CCOHS) says aside from increased irritability, you start losing the ability to do skilled or mental tasks.
As for Dancevic’s loss of consciousness, that was potentially something called heat syncope, a temporary drop in blood flow to the brain which occurs when you’ve lost a lot of body fluid due to sweating and low blood pressure.
That could also have accounted for the dizziness too, but given his prolonged exposure, it was just as likely heat exhaustion.
HEAT EXHAUSTION SETS IN
So far we’ve talked about the strange little symptoms of excessive heat, like heat rashes and blood pooling in the ankles. Heat exhaustion is when you’ve lost enough body fluids and salt that the body starts losing its ability to cope.
As your core temperature rises further above the body’s natural 37oC sweet spot, your sweating gets heavier, your thirst becomes intense, your dizziness increases and you feel increasingly fatigued.