NEW YORK (Reuters Health) — Marathon runners may face an increased risk of skin cancer, Austrian researchers report.Based on the findings, they conclude, long-distance runners should make an effort to reduce their exposure to ultraviolet (UV) radiation by using sunscreen, wearing protective clothing, and organising their training and competition routines accordingly.

Dr. Christina M. Ambros-Rudolph of the Medical University of Graz in Austria and colleagues decided to investigate melanoma risk among long-distance runners after treating eight ultramarathon runners with the disease over a ten-year period.

Along with sun exposure, immunosuppression due to intense training has been proposed as a potential trigger for melanoma, they note in the Archives of Dermatology.

They recruited 210 marathon runners ranging in age from 19 to 71 years for the study, matching them by age and sex with a control group of non-marathoners. Even though men and women in the control group had more signs of sun sensitivity, such as light eye and skin colour and more birthmarks, the marathoners were more likely to have changes in the skin that signal an increased malignant melanoma risk.

And just 56.2 percent of the runners reported using sunscreen regularly, even though nearly all said they ran in shorts and sleeveless or short-sleeved shirts. While the jury is still out on the role of immunosuppression in boosting melanoma risk, Ambros-Rudolph and her colleagues write, “runners should be alerted to the crucial role of UV radiation in the development of malignant melanoma and non-melanoma skin cancer.