It’s not news that it’s been hot. In the middle of a 100-degree day, it might be wise to move to the air conditioning for a workout. But, honestly, isn’t adventuring outside one of the reasons you train?
Exercising in high temperatures intensifies how hard your body needs to work to maintain normal function. As you move, your core temperature naturally rises — the American College of Sports Medicine says core body temperature rises by almost 2 degrees every five minutes.
In order to cool itself, your body sends more blood to the skin in order to cool. Your heart pumps faster to send blood to muscles. Sweat ensues.
Under some circumstances, this can lead to heat illnesses — a plethora ofconditions ranging from mild heat exhaustion to the more-serious heat stroke. Four people — including a mountain biker and an experienced hiker — died last week in Arizona in temperatures that reached 100+. Experts say one of the most important things you can do to stave off heat illnesses is to stay hydrated. But it’s just as important to acclimatize to well before participating in a race or other endurance event.
It can take two weeks or more of regular exposure to heat to fully acclimatize. So be aware of this during workouts this month, and if you feel unusually fatigued or just “strange,” ease off.
Joe Friel, who pretty much wrote the book on endurance cycling training, recommends that for a planned intense workout keep the pace or power the same but shorten the work intervals and lengthen the recoveries (heart rate is not a good indicator of intensity when it’s hot). Be aware that your heart rate will be higher than normal for any given sub-maximal pace or power. Don’t let that concern you. It’s just a part of exercising in hot weather.
Take on some extra water as well — and pour some on your head while you’re at it.
Here are some other tips from Friel:
- Acclimate. It takes 10-14 days of frequent exposure of heat for your body to adapt. After a couple weeks, you can expect to perform better in the heat — but your performance may still be diminished from what you might have done in cooler conditions.
- Stay cool before your workout. Drinking very cold fluids before may help (at least in the short term)
- Stay cool during. Keep the sun out of your eyes and off your face. Pour cool water on your head, but a cool cloth around your neck. Runners may use ice from event aid stations in their hats. Keeping your liquid cool or cold can help. Think about getting an insulated water bottle or bladder (Elevate sells these), and/or freezing part of your bottle and topping it off with water.
- Hydrate appropriately. Be aware that over drinking can lead to hyponatremia; the key is to drink when thirsty. A predetermined schedule can be helpful — let’s say a timer every 15 minutes — but it should not be there to remind you to drink not to force liquid.
- As always, eat well. There are a couple of studies that suggest you may need more carbs and protein before and after a hot workout.
- Sports drinking and electrolyte powders can help head off dehydration and cramps. Investing extra sodium is not an answer, and be more harmful than helpful.
(If you have questions, your coach can help guide you to figure out what might work best for you, so ask!)
Bonus points come fall: A study showed that the effects of proper heat acclimatization — improved sweat response, lowered heart rate, and lowered body temperature — stay with an athlete even when training in cooler temperatures .
Now those are details worth sweating over!