Last summer I was training for a 30k race that was going to take place near the end of August. Because I chose a summer race and summer is, quite frankly, my least favourite season, I knew that I was going to have to be prepared for the crazy temperatures that occur in Toronto in the middle of summer. But even though I was doing everything I knew to protect myself from heat-related illness, there was a long run where, regardless of how much water and Gatorade I drank, I started to get a wicked headache and I wasn’t feeling well. I was beginning to feel heat exhaustion and it almost ended my training but with a few tweaks to my training plan I managed to finish my training without any more risk of illness.
Outdoor exercise is the best exercise you can get but nature can be a finicky bitch so keep your wits about you, have some common sense and you’ll do just fine!
Here is a handy guide to working out in the heat and the risks you need to look out for:
It’s not the heat, it’s the humidity
First thing you need to know is that we’re not just talking about a hot day, we’re talking about a hot day with humidity. In other words, a temperature of 100 degrees and little humidity (like 20 or 30% or less) doesn’t place you at the same risk as a temperature of, say, 90 degrees with a humidity of 60% or more.
The reason why you want to be careful about working out in high humidity is that your body is a natural air conditioner, this is why you sweat. It stores heat and as your core temps begin to rise your body normally will release it through sweat and runny noses. But if the humidity is very high, it puts extra stress on your body. You’re not only raising your body’s temps by exercise but the humidity itself raises its temps. When you start to sweat, the extra humidity will inhibit the sweat from being able to evaporate from your skin and you won’t be able to cool your body down appropriately and your chances of heat cramps/exhaustion/stroke is greatly elevated.
What should I look out for?
When you work out in high humidity, you’ll really want to make sure you tune in to your body to check for signs trouble. If you ignore symptoms you risk passing out, becoming severely dehydrated and possibly even death.
Generally, you want to look for signs of unusual fatigue, weakness, dizziness, nausea, muscle cramps and an increase in body temps.
The following give you more specific details of what to look out for:
- Heat cramps – These are painful muscle contractions, usually in the calves, quads and abs. Although your body temps may be normal, the affected muscles may feel firm to the touch.
- Heat exhaustion. This is where your body temps rise to 104 F and you’ll most likely experience one or more of the following symptoms: vomiting, nausea, fainting, headache, cold and weakness or clammy skin. Heat exhaustion can lead directly to heatstroke if left untreated.
- Heatstroke. This is definitely what you want to avoid as heatstroke can lead to brain damage, organ failure or even death. The biggest indicator would be if you stopped sweating even if your skin is hot and you may experience confusion and/or irritability. If this occurs to you or someone around you, you MUST seek medical attention immediately.
How do I safely work out in the heat?
The good news is that you don’t have to stay indoors all summer out of fear, all you need to do is some advanced planning and common sense. Here are some things to keep in mind:
- Acclimatize yourself – It takes roughly 14 days to adjust to temperature changes so keep that in mind when you’re out so don’t freak out and immediately take your workout indoors when it’s hot, go out for your regular workout but just keep it slow until you get used to it.
- Stay hydrated – This should be a no-brainer but I’m still including it! For any workout over an hour you may want to consider bringing a sports drink with you to replace the electrolytes lost while sweating but for workouts less than an hour, water is fine. Don’t wait until you’re thirsty to drink though, that’ll be too late, have a few sips every 10 – 20 minutes and make sure to drink a cup or two immediately before and after your workouts.
- Avoid the hottest part of the day – Unless you have a race during these times, avoid working out between 10am and 3pm as this is when temperatures are at its peak. Try instead to work out earlier in the morning or later in the evening when it’s cooler.
- Wear light, loose fitting clothes – And make sure it’s made out of a material that “wicks” away your sweat so your body can cool itself better and wear a hat!
- Wear sunscreen – Sunburns inhibit the bodies ability to stay cool so make sure you wear sunscreen. Plus, skin cancer sucks.
- Have a backup plan – If the humidity is insanely hot (i.e., if there’s a heat alert in your city) don’t be a hero and take your workouts indoors. I feel absolutely no admiration for people who work out in dangerous temps so make sure you have a backup plan in place.
- Be aware of your prescriptions – This is a surprising tip I’ve learned. Many medications and prescriptions can increase your chance of heat-related illnesses by promoting heat storage or impairing sweat glands. People taking medications such as antipsychotic medications, antihistamines, antidepressants, and even some muscle relaxants could interfere with sweating so talk to your doctor before heading outdoors.