Workouts in the heat can seriously boost your fitness. For one, the heat makes you stronger. There’s a reason that some of the best marathoners in the world hail from countries where winter is an 80-degree day. When you train in the heat, you sweat. Sweating tells your body to send blood to the surface of your skin to aid in cooling you down, and that means there is a decrease in blood volume and oxygen going to your muscles. That sounds like a bad thing, but over time your body adapts, forcing itself to do more with less during a workout. Then, when the temperature drops in the fall and suddenly all that oxygen-rich blood starts pumping into your muscles, you find yourself measurably fitter than you were in the summer. (In one study, cyclists who biked for 10 sessions in 100° F heat, followed by a time trial in 55° F, experienced a 7 percent increase in their performance.)
But, of course, heat has its downsides. Working out in extreme summer heat makes everything feel harder. As a rule of thumb, for every 10 degrees above 50° F, your aerobic fitness performance suffers by around 3 percent. In one study, people biking in 100° F conditions experienced a 9 percent drop in pace compared to a group biking in 68° F conditions. “When you work out in the heat, you increase your core body temperature more quickly,” explains Kami Blease, a Los Angeles-based personal trainer for Fyt, the nation’s largest personal training service. “This makes your body work harder to cool you off, therefore increasing your heart rate” and your sense of exertion. As a result, you run slower and lift lighter — and still feel just as tired as if you’d crushed your workout goals. That’s not to mention heat exhaustion and dehydration — side effects of pushing it too hard on a hot day.
How To Use Heat To Get Fit
Hot day workouts should embrace short bursts. Research also shows that short-duration physical activities — i.e. sprints — can improve in the heat (possibly because your muscle fibers and ligaments are extra-limber and the bouts of work aren’t long enough to really stress your aerobic system). Similarly, some studies show that when heat is applied directly to muscles during an abbreviated weights session, performance is enhanced.
So, “you can still work out in the heat,” says Blease. You just “need to be more aware of how your body responds to movement in those conditions. If you want a strength workout, I recommend something short and sweet. Think of compound movements like a squat with an overhead press or walking lunges with a biceps curl.” Working multiple body parts at once gives you a more intense, but shorter, workout, she adds. Just make sure to give your body ample rest, whether between lifting sets or bouts of cardio.
As for which is better in sauna-like conditions, cardio, or strength, Blease is noncommittal. “It’s less about the type of exercise and more about how you prepare and pace yourself when working out in the heat,” she says. With that in mind, check out these two workout plans—one for cardio, one for strength — for steamy summer days.
Your Summer Heat Cardio Workout
- Warm up: 5 minutes fast walking
- 3 x 60-second sprints; 60 seconds of recovery between sprints
- 5 x 20-second sprints; 30 seconds of recovery between sprints
- 10 x 10-second sprints; 20 seconds of recovery between sprints
- Cool down: 5 minutes slow jogging or walking
Your Summer Heat Strength Workout
- Squat with Overhead Press
How to: Stand with feet hip-width apart, holding weights (or water jugs) at your shoulders. Squat until legs are bent to 90 degrees. (“Think about sitting down and back like you would sit in a chair, keeping most of the weight in your heels,” says Blease.) Stand and press weights overhead, palms facing in.
How many: 3 sets of 10 reps; 60-second rest between sets
- Pushup with a Row
How to: Start in an extended plank position, feet slightly wider than hips and hands slightly outside shoulders. Place weight on ground between your hands. Lower into your pushup, guiding elbows back around 45 degrees; press back up to plank position. Pick the weight up with your right hand, keeping your elbow close to your body, and “row” the weight toward your chest. (“Think more of a scoop back rather than pulling it straight up,” says Blease.) Do a row on both sides, and then start again with your pushup.
How many: 3 sets of 6-8 reps on each side; 60-second rest between sets
- Walking Lunge with Biceps Curl
How to: Hold the weights or water jugs down by either side. Take large step forward so that both knees can comfortably bend to about 90 degrees. Drive front knee forward without letting it go over your toes. As you straighten your legs and pick up your back foot to bring it to meet your front, curl the weights towards your shoulders, leading with your palms. Release the weights as you stand fully up with your feet together and then step forward on the opposite side and repeat.
How many: 3 sets of 10-12 reps; 60-second rest between sets
Feeling ambitious? Repeat this circuit again!
Tips And Tricks For Working Out In The Heat:
- Go hard—but short. Save the mile repeats for a cooler day. High temps are ideal for distances between 100 and 400 meters — that’s a quarter to full lap around a standard track. (Don’t have a track or meter markers? Run hard for 20-45 seconds, then walk for equal time to recover.)
- Dress wet. If you’re heading out into the heat for a sweat session, give yourself a head start by soaking your shirt and shorts in cold water, wringing them out, and putting them on. Looking, the things are going to be drenched in sweat in another 10 minutes anyway. This way, you’ll give your body temp a slight dip to get started.
- Dress cold. Another time-honored tip summer runners swear by: Store your workout clothes in the freezer overnight.
- Do hard things first. Start with your hardest sets. Think: Bavarian split squats while holding a gallon jug of water in each hand, 8 reps x 2 sets, then switch to standard squats.
- Make hydration part of your workout. Weighted vests are trendy, but can you drink them? Instead, grab two 1.5 liter water bottles and carry one in each hand as you jog. When you’re thirsty, drink. When you’re not, you’ll be give your forearms and biceps a (small) workout as you swing your arms back and forward on your run. (Top tip from the American Council on Exercise: Add a pinch of salt to your water bottle — it has the same effect of boosting electrolytes as a sports drink for a fraction of the price.)
- Find shade. “While you might want to work out in the heat, you don’t necessarily have to work out in the sun,” says Blease. “Try to find shady spots, wear a hat, and apply sunscreen.”