Working out in hot weather is safe for most healthy people if you take a few precautions: train in the cooler parts of the day, drink water before, during and after, ease into the heat over a couple of weeks and know the warning signs of heat illness. Boston summers bring high humidity, and humidity makes heat feel even harder on your body. Here’s how to stay safe and keep training through the summer.
How heat affects your workout
When it’s hot, your body works harder to cool itself. Your heart rate rises, you sweat more and you lose fluids and salt faster. Humidity makes it worse, because sweat doesn’t evaporate as easily, so your body can’t cool down as well.
That’s why the same run or workout can feel much harder in July than in October. It’s normal to slow down in the heat.
Tips for working out in hot weather
Pick the right time
Early morning and evening are the coolest parts of the day. Avoid hard outdoor workouts in the middle of the afternoon on hot, humid days.
Hydrate before, during and after
- Drink water through the day, not just at the gym
- Have a glass or two of water an hour or so before you train
- Sip during your workout, especially if it’s longer than 30 minutes
- On long, sweaty sessions, an electrolyte drink can help replace the salt you lose
- After training, keep drinking until your urine is pale yellow
Ease into it
Your body adapts to heat over about one to two weeks. During the first hot stretch of summer, go a little shorter and easier than usual and build back up.
Dress for the heat
Wear light colored, loose, breathable clothes. If you’re outside, add a hat and sunscreen.
Lower the intensity
On really hot days, it’s fine to go slower, take more breaks or swap a hard session for an easier one. Pushing too hard in the heat isn’t worth the risk.
Move your workout indoors
When the heat index climbs, training in an air conditioned gym is the easiest way to stay consistent. Lifting, classes and cardio machines let you keep your routine without battling the weather.
Know the warning signs
Heat illness can come on fast. Stop exercising, get somewhere cool and drink fluids if you notice:
- Heavy sweating, cold or clammy skin
- Dizziness or lightheadedness
- Headache or nausea
- Muscle cramps
- Unusual weakness or fatigue
Get emergency help right away if someone becomes confused, stops sweating, has hot dry skin, faints or has a very high body temperature. These can be signs of heat stroke, which is a medical emergency.
People who are older, have certain health conditions or take some medications can be more sensitive to heat. If that’s you, check with your doctor about exercising in hot weather.
Summer is a great time to get stronger
The heat is a good reason to move some of your training inside and focus on strength. Longer days and lighter schedules make summer a great time to build a routine:
- Strength train two or three times a week in an air conditioned gym
- Keep outdoor cardio to cooler mornings and evenings
- Use a Spin class for a hard cardio workout without the sun
- Set a summer goal, like adding weight to your squat or finishing four weeks of consistent training
Four steady weeks can make a noticeable difference in how you feel. For more on that, read Consistency in Fitness: How Small Efforts Add Up.
Eat for hot weather
Hot days can kill your appetite, but your body still needs fuel. Water rich foods like watermelon, cucumbers, berries and tomatoes help with hydration, and a little salt with meals helps replace what you sweat out. Read more about tomatoes for athletes.
Train in the air conditioning at Mike’s Fitness JP
When it’s too hot outside, Mike’s Fitness JP gives you more than 15,000 square feet of air conditioned space to train, with more squat racks than most gyms in the city, plus free weights, machines and cardio. Every membership includes every group class, and there are no contracts and no start up fees.
The gym is a short walk from the Stony Brook stop on the Orange Line, with free parking right at the building, and it’s open from 5:30 AM to 10 PM on weekdays, so you can train early or late when it’s cooler out.
New to the gym? Every membership includes a free fitness assessment with a certified trainer. If you want more structure for the summer, look at personal training.
Stay cool, stay consistent
Hot weather doesn’t have to stop your progress. Train smart, drink plenty of water, listen to your body and move inside when the heat gets serious. You’ll come out of summer stronger.
