The Worst Summer Exercise Mistakes

Warm weather is the ultimate motivation to get outside and start moving. But don’t get burned by these hot weather slip-ups

June 10, 2011
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You don't have to be a meteorologist to know this summer is going to be a hot one. Outdoor exercise is a perk of warmer days, but when temperatures skyrocket, you're at greater risk for dehydration, sunburn, and even chafing. But staying safe (and comfortable) in the sun requires more than just the occasional slap of sunscreen. Here, the 11 worst summer exercise habits that'll leave you hot and bothered--and how to fix them. (Looking to change up your exercise routine? Try these perfect yoga positions for summer.)

Slim, Calm, Sexy Yoga: Get a Yoga-Slim Body in Just 15 Minutes a Day!

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Drinking Hot Coffee Before Your Run

Sure, drinking java has been shown to help you run faster and work out longer, but you might want to limit your prejog joe during the summer months. The caffeine in coffee acts as a diuretic and may increase your chances of dehydration if you drink more than 5 cups. And, if you like your brew hot, you could be hurting your performance. A study published in the journal Medicine & Science in Sports & Exercise found that cooling your body before a run could enhance performance. People who drank an ice-cold slushie before working out in the heat were able to run longer and felt less exhausted than those who drank cold water.

Just because it's hot out doesn't mean you have to lay off exercise. Find out how you can run off 10, 20, even 30 pounds when you pick up a copy of Run Your Butt Off!

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Wearing Too Loose Clothing

No one wants to feel like their legs are stuck in spandex sausage casing, but sprinting around with flapping shorts can increase your chances of chafing. Add summer sweat to the mix and you'll exacerbate the burn. If you're prone to chafing, invest in BodyGlide or petroleum jelly and try wearing spandex underneath your running shorts, says Chris Travers, an exercise physiologist at the Cleveland Clinic. When picking out a pair, you don't want the fit to be too tight or too loose--both will create friction and rubbing. Take a look at the seams to make sure that they're not too rough or raised.

Another tip from Travers: The stiffness of brand-new clothing can up your chances of chafing, so give them a wash before wearing.

Search: The best running shorts

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Not Eating After a Workout

When it's hot as blazes, you may find your cravings for heavy, filling foods falls by the wayside. The appetite-curbing power of heat holds true after a workout, too. A study in the American Journal of Clinical Nutrition found that people who worked out in hotter temperatures (97°F) ate 300 fewer calories at their next meal than those who exercised in cooler temps (77°F). While cutting back on calories isn't necessarily a bad thing, be mindful to refuel properly after your workout. You should eat a snack that has both carbs and protein within 30 minutes after your workout to replenish your glycogen (aka quick energy) supply, as well as to stop your muscles from breaking down. For people who don't feel like eating at all after a summer workout, try replenishing with liquid calories, such as a sports drink containing whey protein, recommends Chris Mohr, PhD, RD, of Mohr Results in Louisville, KY. You're getting in needed calories and rehydrating your body.

Video: What to eat after a workout

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Wearing a Hot, Black Number

Black exercise tanks may be slimming, but they trap heat. "Darker clothes are going to hold more heat than lighter-colored outfits, so you're going to want to avoid the blacks, dark blues, and dark grays when it's sunny out," says Travers. While it's true that darker clothes tend to block the sun's UV rays better than lighter options, sports apparel companies are making tops treated with chemicals that add UV protection. Merino wool products also naturally block the sun's rays better than other fabric blends. Stay cool and still look chic with Icebreaker's GT Run Rush tank in ember or cove. The lightweight merino wool shirts are wrinkle-free, naturally anti-odor, protect you from UV rays, and are cute, to boot.

Bonus: Check out the winners of our 2011 summer running shoe guide

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Forgetting to Hydrate at the Pool

Playing in water isn't the same as drinking it. "Because swimmers are in the water, it can be easy to overlook how much water the body loses through sweat as compared with exercise on land," says Jeffrey Chu, a swim coach with the Three Village Swim Club in East Setauket, NY, and a member of the USA Swimming National Committee for Safety Education. When you can't feel your sweat, your body misses its cue to hydrate. Plus, because water transfers heat more quickly than air, swimming in warm water can make it harder for you to dissipate heat produced while working out. It's harder for you to cool off, making it all the more important to stay hydrated.

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Only Drinking Water During Your Workout

Whether you're in the water or on land, you're probably already slightly dehydrated by the time you feel thirsty. To avoid muscle cramps and dehydration, you need to drink up before, during, and after your sweat session. Drink 17 to 20 ounces of water 2 to 3 hours before you workout and gulp another 8 ounces during your warm-up. While exercising, you should take in another 7 to 10 ounces every 15 minutes or so. When you're done, remember to rehydrate and weigh yourself: Drink 8 ounces in the 30 minutes following a workout, and an additional 16 to 24 ounces for every pound of water weight you sweated out.

Related: 12 ways to make water less boring

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Trying to Reach a New PR

Everything tends to slow down in the summer, including your split times. It's for good reason, too: Trying to reach a new PR in hot conditions isn't just unrealistic, it's also dangerous. When you're exerting yourself in warmer temperatures, core temperatures rise faster, as does your heart rate--putting you at risk for heat stress. [When you run on a hot day], "you perspire more, so you're losing fluids and electrolytes at a more rapid rate, and it's harder to breathe when it's humid outside," says Travers.

Instead of focusing solely on how fast you're running, tune in to how your body is feeling. Keeping track of your heart rate might be a better indicator of how hard you're working as compared with how fast you're running. If you're going to go out for a hard run, or for speed work, you're better off going early in the morning or even taking it indoors.

Want more great running tips? Sign up for a full year of Runner's World magazine and get the scoop from insiders.

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Going Shirtless

When you're sweating buckets, it sure feels a lot nicer to lose the cotton shirt, but you're also putting yourself at greater risk for sun damage. Whether your shirt is on or off, make sure you apply at least 1 ounce (the amount it takes to fill a shot glass) of sunscreen on all exposed parts, recommends the American Academy of Dermatology. Slather on a sweat-proof lotion with an SPF of 30 or higher.

For additional coverage, wear a wicking shirt, like the TNP T by Under Armour. "Shirts like these have sunscreen built in," says Mohr, who is also a spokesperson for Under Armour. "They cool you and protect you--so that's a win-win."

Related: Gear to keep you going

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Sleeping In

Lazy weekends are nice, but don't even think about pushing off your morning sweat session by an hour during the summer. It gets too hot, too fast, and you're putting yourself at greater risk for heat exhaustion. Avoid exercising outside from 11 a.m. to 3 p.m.--the hottest times of the day--and aim to head out early in the morning or during the evening when the temperatures are cooler.

If you waited too long to start your outdoor routine, try this fun living room workout instead!

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Cycling Without a Helmet…

It can be tempting to toss your helmet when it's humid out, but committing this cardinal safety sin won't actually make you any cooler. Ball State University researchers found that cyclists who wore helmets in hot-dry conditions and hot-humid conditions were no hotter than those who went helmetless. However, some helmets do trap heat--especially if you're using one from 6 or 7 years ago. So pick one that maximizes airflow. "Try on a helmet, then look in a mirror," says Don Palermini, director of marketing at Bell Sports. "If you can see through the top few vents and out the back of the helmet--something good channeling allows--then it's likely you'll be more comfortable."

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…Or Choosing the Wrong One

Contrary to what you might think, more vents in a helmet don't equal better cooling. Fewer large vents that connect to channels within the helmet liner help air flow better than a lot of smaller vents that let air in, but don't direct it out. It also helps to match your helmet to the kind of cycling you do, says Palermini. A good mountain bike helmet generally has larger, wider vents on top that help dissipate heat  when you are moving at slow speeds, like when you're climbing a steep trail. A good road cycling helmet tends to have longer vents that do a better job at moving air through when you are going faster.

Next Up: How to sun-proof your summer workout