According to the latest study carried out by European scientists, marathoners face increased likelihood of skin cancer, including melanoma.
The research "confirms things we are already aware of," stated Dr Robin Ashinoff, chief of dermatologic, Mohs, and laser surgery at Hackensack University Medical Centre in Hackensack, New Jersey. "We ought to be counseling these people to try and do their outside activities not in the sunny weather, to wear a hat when the sun is the strongest, T-shirt, long sleeves, and to put on sun block. They’re at great risk."
As far as background information in the research is concerned, there is evidence indicating that endurance exercise, such as marathon running, may increase the risk of skin cancer. Not only are outdoor sportsmen exposed to enormous levels of ultraviolet radiation, but invigorating exercise may stifle the immune system.
Golfers and tennis players are also at high risk
"Each person spending a lot of time outdoors - runners, bicyclists, golfers, tennis players - all have a lot of sun damage," explained Ashinoff, who wasn’t engaged in the current research.
"People spending more time in the sun are at elevated melanoma risk," added Dr Vijay Trisal, assistant professor of surgical oncology at City of Hope Cancer Centre in Duarte, California.
Melanoma constitutes one of the deadliest and most destructive type of cancer. Other types of skin cancer, like basal cell carcinoma and squamous cell carcinoma, for example, are usually less fatal but can be disfiguring.
The Austrian authors o the research, themselves enthusiastic runners, treated eight ultra marathon runners with malignant melanoma in the previous decade. All of the melanomas were situated in parts of the body that were not covered or were only partly covered by clothing in the course of physical activity.
How the research was performed
For this research, the group of specialists from the Medical University of Graz recruited 210 marathon runners (166 of them men), between 19 and 71 years of age, at a local marathon and compared them with 210 controls recruited at a skin cancer screening campaign.
All partakers were checked for skin cancer and filled in a questionnaire concerning any personal and family history of skin cancer, sun sensitivity and sun exposure. Marathoners also answered several questions concerning their training.
Controls appeared to be more sensitive to the sun (meaning they had lighter eyes and more sensitive skin types). However, the marathoners had more dysplastic nevi (unusual moles, that can become malignant melanoma) and more liver spots. The more extreme the training regimen, the more pronounced the irregularities.
As a consequence of their involvement in the research, twenty four marathoners and fourteen people in the control group were referred to dermatologists for probable non-melanoma skin cancer.
The vast majority of the marathoners (96.7 percent) said that they wore shorts and short-sleeved or sleeveless shirts. Only 56.2 percent admitted that they regularly used sunscreen while training or competing, whereas 41.9 percent admitted that they used it sporadically, and 1.9 percent said they never used it.
Marathoners and other outdoor sportsmen should stick to some common-sense rules, Trisal explained, such as "don’t spend time outdoors at midday, wear a wide-brimmed hat and a sunscreen of more than 15 SPF."
Emergency for whole body
"Everything that makes you happy and feel really good is, somewhat, good for your health. Nevertheless, it is currently well established that invigorating exercise, and especially marathons/ultra marathons, symbolize emergency states for the whole body," said Dr Christina M. Ambros-Rudolph, a lead author of the research and a dermatologist at the Medical University of Graz.
"Taking sunscreen alone is not sufficient procedure due to the fact that it can lose its power with sweating. It would be essential to keep away from training in sun-peak hours (11 am to 3 pm) and wear sensible gear covering shoulders and upper back," she added.
Ambros-Rudolph and her team are now finishing a follow-up research.
