Summer is a great time for outdoor activities: the days are long and warm, and there are plenty of things to do, whether it be swimming, cycling, kayaking or going for a walk. But summer has its own hazards that can present challenges: extreme heat, humidity, poor air quality and the sun’s UV rays are just a few of the things to consider when planning a warm weather workout.
Registered kinesiologist Faith Delos-Reyes, program coordinator and exercise specialist with the Women’s Cardiovascular Health Initiative at Women’s College Hospital, notes that some of the most serious dangers in hot weather are dehydration, heat exhaustion and heat stroke.
To stay hydrated, drink water before, during and after exercising, but don’t just think about hydration when you’re active.
“Think about hydration all day, and aim to drink two to three litres (nine to 12 cups) of water a day. Don’t just chug water before a workout,” Delos-Reyes says. “Choose healthy snacks such as fruit that help keep you hydrated, and stay away from coffee before and after a workout because caffeine is a mild diuretic. It’s a good idea for adults to limit their caffeine intake to 400 milligrams per day, which is about three cups of coffee.”
Even if it’s hot, don’t neglect your warm-up. Delos-Reyes notes that warming up and cooling down are still important in hot weather, because it’s harder for your body to recover from exertion if you start and stop vigorous activity abruptly.
When, where and how
To get the most out of summer while beating the heat, Delos-Reyes recommends thinking about when, where and how you exercise in hot weather.
“The best times for working out outdoors in warm weather are early morning and in the evening,” she says. “Stay out of the sun from 10 a.m. to 4 p.m. when the sun is at its most intense.”
Exercising in hot weather puts extra stress on the body. Exercise itself, as well as air temperature, increases core body temperature. You may want to think about modifying your regular workout in hot and humid weather.
“Do the activities you’re used to doing, but take the pace down a bit,” Delos-Reyes suggests. “For example, if you usually walk briskly to work, walk a bit more slowly in the heat or decrease walking duration. If playing a sport, play it a little less intensely. For example, if you are playing tennis, forget the one-bounce rule during hot weather: agree to adjust the rules to let the ball bounce twice if you need to so you don’t have to keep sprinting across the court.”
Another option is to consider water sports, such as swimming or aquafitness, that help keep you cool. Alternatively, you might want to do activities that are less vigorous, such as gardening.
Think about where to exercise in the heat. Choose shady areas or cloudy times of day over direct sun.
“For example, if you like to walk, choose a shaded walking path in an area with trees instead of a walk on the boardwalk in constant direct sun,” says Delos-Reyes. “Wear sunscreen, a hat, light-coloured clothing and good walking shoes. Even though it’s summer, don’t wear flip-flops because they offer no support or protection for your feet.”
Be mindful of the potential hazards of warm weather workouts. Use weather forecasts and air quality reports as a guideline for when to take your workout indoors.
“If there is a public warning about extreme heat, smog or poor air quality, or a warning about high weather-related risks to elderly people or children, don’t exercise outdoors,” Delos-Reyes says. “You might want to try indoor activities such as fitness class, spinning or yoga classes, or mall walking, instead.”
Be alert to the danger signs of heat exhaustion:
- dizziness or lightheadedness
- nausea or vomiting
- fatigue or weakness
- headache or confusion
- unusual shortness of breath
- rapid heart rate
- profuse sweating
“If you are experiencing symptoms of heat exhaustion, stop what you are doing, cool your body and rehydrate by drinking lots of water. Rest, go to the nearest cool and shaded area, take a cool shower or use cold compresses,” says Delos-Reyes. “Heat exhaustion can lead to heat stroke, so if you experience any of the above symptoms, you want to treat them.”
Heat stroke has more extreme symptoms, such as muscle cramping, seizures, fainting, or ceasing to sweat despite the heat. Heat stroke is life-threatening. It is defined as core body temperature of 105 F or 40 C. Heat stroke is a medical emergency: call 911 or go to the emergency department.
This information is provided by Women’s College Hospital and is not intended to replace the medical advice of your doctor or health care provider. Please consult your health care provider for advice about a specific medical condition. This document was last reviewed on: Aug. 11, 2015