As the dog days of summer hit, you may be tempted to abandon running for jumping through a sprinkler or napping in a hammock. If that makes you feel a little guilty, take heart: It’s not (just) laziness—it’s self-preservation. “When the outside temperature increases, our bodies can’t dissipate heat as effectively,” says exercise physiologist Julia Moffitt, Ph.D., assistant professor of physiology and pharmacology at Des Moines University. “Therefore, our bodies have a natural inclination to become less active.” Add other hot-weather roadblocks, such as allergies, dehydration, and even interrupted sleep, and you may think about storing your running shoes in the closet until fall. Not so fast. Your performance doesn’t have to suffer just because temperatures are ramping up. Here’s how to put the sizzle back into your summer running.
Summer Setback: HOT TEMPS MAKE YOU LAZY
“When we go out in the cold, our brain tells our muscles to contract, which generates heat to keep us warm,” Moffitt says. When it’s hot, the opposite happens: The brain instructs the muscles to relax to keep body temperature from increasing. “That’s why you may feel more motivated to hang out under a shade tree—it’s your body’s attempt to avoid overheating,” says Moffitt. Also, the process of sweating to stay cool diverts blood away from muscles, which may leave them feeling sluggish.
COOL RUNNING Avoid that lethargic feeling by easing into hot-weather running, says Moffitt. Do your main workouts before 10 a.m. or after 6 p.m., and go for a 15-to 20-minute light run or walk in the heat of the day. Increase the intensity and length of your hot workouts by five to 10 minutes over two weeks. Allow even more time to adjust to humid environments, and replace fluids lost through sweating with sports drinks. “When we are gradually exposed to warm environments, our bodies respond by being able to more efficiently distribute blood flow, which helps us increase sweat production so we can maintain effort without overheating,” Moffitt says. To stay cool during a run, dump water over your head, which will help drop your core temperature, says Lewis Maharam, M.D., medical director for the Rock ‘n’ Roll Marathon Series. Also, a recent study shows that runners who drink ice slushies run about 10 minutes longer than when they have a cold drink.
Summer Setback: AH-AH-AH-CHOO!
Pollen from ragweed, Bermuda grass, Blue grasses, and Red Top grass are common during the summer, and if you’re susceptible to allergies, running can exacerbate symptoms, such as itchy eyes, sneezing, and congestion. “Runners have a higher respiratory rate than less active people do, which brings more pollen into the nose and lungs,” says Nathanael S. Horne, M.D., an allergy and asthma specialist in New York City.
COOL RUNNING Pollen counts are often highest between 5 a.m. and 10 a.m., so you might find relief by running later in the day, Horne says. Allergy sufferers should check pollen.com for updates and hit the treadmill when pollen counts are very high. Shower immediately after running; pollen that settles on hair, clothes, and eyelids can continue to trigger reactions. Runners with contacts might fare better wearing their glasses, which may serve as a shield. Because rain often removes pollen from the air, Horne says you might want to lace up after a storm. You can also try an antihistamine such as loratadine or cetirizine.
Summer Setback: LONGER DAYS = SHORTER NIGHTS = LESS SLEEP
The additional hours of light during the summer reduce production of melatonin, a hormone that makes you feel sleepy. This may keep you up later and wake you earlier. “Even if you are sleep-deprived by only a couple of hours, your normal run can seem harder,” Moffitt says. Skimping on shut-eye during the summer can be especially problematic if you’re training for a fall marathon, as sleep is important for muscle recovery after long runs.
COOL RUNNING Evening runs mean cooler temperatures and less pollen, but don’t head out too late. Your brain will be stimulated and your heart rate and body temperature will be elevated for two hours after your run. To ward off night sweats that could disrupt your sleep, the National Sleep Foundation recommends using an air conditioner or fan to keep your bedroom cool (between 55 and 75° F). And use black-out window shades to block out early-morning sun.
Summer Setback: SUPERSWEATY WORKOUTS LEAVE YOU DEHYDRATED
According to a recent British review, losing just two percent of your body weight through sweating and dehydration can diminish your running performance up to 20 percent and as much as 60 percent in a hot environment. More important, heat illnesses, such as cramps and heat exhaustion, can begin when core temperature rises only a few degrees above normal, often related to dehydration from sweat losses (see “Danger Zone,” below).
COOL RUNNING Start by determining your sweat rate, says Mindy Millard-Stafford, Ph.D., director of the exercise physiology laboratory at the Georgia Institute of Technology in Atlanta. Weigh yourself naked on a digital scale before and after a run. For every pound of weight loss, rehydrate with 16 ounces of fluid. When you run, sip a sports drink or water when you’re thirsty, but don’t drink more than the amount determined by your sweat rate. To replace salt and other electrolytes lost through sweat, eat a snack such as baked pita chips dipped in almond butter after a run.
Recognize—and deal with—harmful heat ailments.
SPOT IT Spasms in the abdomen, arms, calves, or hamstrings
TREAT IT Stop running for the day; sip sports drink; gently massage the cramp.
SPOT IT Heavy sweating, headache, dizziness, nausea
TREAT IT Stop running; get in shade; sip sports drink; see a doctor if symptoms continue.
SPOT IT Confusion, rapid breathing, fainting, cessation of sweating
TREAT IT Stop running; call for emergency help; get in shade; cool skin with water.
Sunblock vs. Vitamin D
A RECENT STUDY reports that many runners are low on vitamin D, a nutrient our bodies make by absorbing sunlight. Another study reports that marathoners show an increased risk for skin cancer. So how should we approach sun protection? Experts say wear sunscreen (SPF 30 or higher) while running. If you aren’t prone to sunburn, get 10 minutes of midday sun exposure three times a week. If you are, take a multivitamin. “Most daily multivitamins contain 200 to 400 IU of vitamin D,” says dermatologist Barbara A. Gilchrest, M.D. “That’s more than enough for a healthy runner who inevitably gets some sun. Even with a layer of SPF sunscreen, 20 percent of the sun’s UVB rays will enter the skin and produce the maximum daily amount of vitamin D your body needs.”