When exercising in July and August in the Mid-South, it's not just hot outside. It's hot inside, too. Actually, it's hot inside you .
According to SportsDoctor.com, exercise "increases internal heat production 15 to 20 times more than at resting levels." Our brain — specifically, the hypothalamus — does what it can to regulate the temperature increase by opening our sweat glands and dilating surface blood vessels. But there's only so much heat a body can take before the dangers of hyperthermia set in. Beyond the obvious tips — drink fluids before and after exercise, avoid caffeine and alcohol, exercise in the morning or evening — what can a Memphian do to exercise in extreme heat and remain healthy?
Mike Stark is entering his eighth year as the University of Memphis football team's strength and conditioning coach. When preseason camp starts each August, Stark is responsible for roughly 100 athletes training in temperatures that aren't exactly "football weather." A key element to conditioning the Tiger players is acclimating them over the summer through incremental exposure to the heat. Starting in June, the players will run one day a week at 1:30 p.m. When the second cycle of Stark's program starts in July, the athletes will do this run three times a week.
Stark advises his players to drink eight ounces of water for every 25 pounds of body weight. "Water is the body's gasoline," he notes. "And with water making up 70 percent of your body, you really can't get too much when it comes to running in what most people consider unbearable heat." As for dangerous symptoms, Stark and the U of M coaching staff look carefully for an athlete who is not sweating. That's the kind of danger sign that could lead to heatstroke, and will end an athlete's training day. When asked if there are any virtues to training in extreme heat, Stark says mental toughness. "[Football players] that mentally won't, physically don't."
For the gizmo-and-gadget set, there are myriad items that — depending on your faith in the product — can help you fight heat and stay healthy during summer exercise:
> Camelbak has a hip-mounted water system called FlashFlo that allows you to carry 45 ounces of water strapped to your waist (yes, like a camel). The pack even has pockets for wallets, small purses, and keys. (outdoorsinc.com) $40.
> Patagonia's Airius running hat is designed for endurance training. Lightweight and made of a fast-drying polyester fabric, it's the hat you see on marathoners. (outdoorsinc.com) $25.
> SunGuard is an additive that, when combined with your laundry detergent, penetrates the fibers of your clothes and absorbs UV light (as opposed to allowing it to pass through the fabric to your skin). A single treatment is said to provide protection for up to 20 washings. A single box is just $1.99. (sunguardsunprotection.com).
> Polar offers a sports bra with a built-in transmitter belt to monitor your heart rate. (polar-heartrate-monitors.com) $34.95.
Whatever tools you choose to help fight the oppression of a Memphis summer, be warned that they may comfort, but they cannot cure. Dr. Kevin Newman is a cardiologist and associate professor at the University of Tennessee Health Sciences Center. Dealing largely with heart patients, he has a keen awareness of the hazards of exerting oneself in extreme heat. He goes so far as to advise his patients not to exercise outside when the temperature is above 80 degrees.
Newman defines the basic problem as "heat dissipation and not enough of the blood flow going to the vital organs that the heart depends on, such as the kidneys." Newman has seen his share of heart-failure patients who succumb to the extreme heat, so he advises caution for anyone even remotely susceptible to heart-related ailments. "I'm not telling someone to not exercise in the heat," he stresses. "If they're used to it, and they're in good condition, it's fine. But generally speaking, there are no virtues to exercising in the heat over doing so in an air-conditioned environment. And it can be especially dangerous for the elderly."
Newman adds that lengthy exposure to heat is worse than a brief, intense period of exercise. And the more stress on muscles, the more dangerous the activity in the heat. So take those images of weightlifters on the beach and toss them out of your consciousness. Perhaps the best tip of all for getting the most out of your body during a Memphis summer is as elementary as a grade-school admonishment: Use your brain.
Carson Irwin contributed to this story.