You can't outrun the sun. Not even if you're a 2:46 marathoner like Carwyn Sharp, Ph. D. Last August, the Houston-based exercise scientist was diagnosed with invasive malignant melanoma, the most serious form of skin cancer; it kills about 7,500 Americans every year. Luckily, Sharp's cancerous mole on his right ear and a portion of his lobe were removed before the melanoma had spread. "For me, skin cancer was out of sight, out of mind," says Sharp, 35, who grew up in Australia and wore sunscreen infrequently. "Like a lot of runners, I didn't think about it."
While no studies specifically indicate that runners suffer higher rates of skin cancer, experts believe that outdoor athletes are more prone. "If you run outside with your body exposed to the sun, your skin gets damaged, and that increases your risk of skin cancer," says Peter O'Neill, M. D., a dermatologist and marathoner from Garden City, New York.
Despite such warnings, the same health-conscious people who shun smoky restaurants and fast-food joints don't seem as concerned about the potential danger of running in the sun. A 2005 study reported that 85 percent of outdoor athletes didn't use sunscreen at all.
"I think runners have some resistance to it," Dr. O'Neill says. "Your watch, your replacement drink, your shoes ... these are all things that have a direct impact on the quality of your run. You should be doing things to protect your skin, but that pay-o ff may seem vague and distant."
It was for Sharp—until he was having a chunk of his ear removed. Now that the threat of cancer is real, he's doing all he can to prevent another bout, including running before sunrise and wearing sunscreen even under his clothes. By taking these simple precautions, you too can run safely outdoors this summer.