Research conducted in the department of dermatology and venereology at the Sisters of Charity Hospital in Zagreb, Croatia suggests athletes who frequently train outdoors need better education on sun-smart behaviour. A study published in the journal Acta Dermatovenerologica Croatica (July 28, 2020; (1):41-42), recommends athletes avoid training and competing in periods with high sun exposure. The researchers also propose athletes wear adequate clothing and apply water-resistant, high protection sunscreen regularly. Additionally, screening for skin cancer should be performed on athletes at high risk, such as triathletes.
“UV exposure is usually exceeded in most activities performed outdoors with exposed skin, even if they are performed in sunny conditions for only a short amount of time,” the study’s authors wrote.
Athletes practicing and competing outdoors are exposed to considerable UV radiation and are at an increased risk for the development of UV-related skin conditions, such as skin cancer, according to the study’s authors.
The researchers note that the risk factors for skin cancer include genetics, immune status and particularly UV radiation. Independent factors, such as phototype, family or personal history of melanoma, number of nevi, atypical nevi and solar lentigines, as well as sunburn history are also important risk indicators for skin cancer, especially melanoma. Further, exercise-induced immunosuppression may contribute to the development of skin cancers.
To analyze the effects of UV exposure on athletes who train outdoors, researchers studied the sun protection habits of athletes competing in the Croatian Olympic triathlon and Super Sprint triathlon and screened them for skin cancer and other skin lesions.
Participants completed a questionnaire consisting of questions regarding personal and family history, phenotypic characteristics, training habits, and sunlight-related risk factors. A total body skin examination was performed by a dermatologist. Skin type, number of melanocytic nevi, presence of atypical nevi, solar lentigines, as well as suspicious lesions were recorded.
The study included 95 participants, 65 (68%) men, and 30 (32%) women. Approximately 30% of participants spent four to six hours per week outdoors, while 21% spent more than 10 hours outdoors per week.
With regard to sun protection habits, more than 90% of participants stated it was important to use sunscreen. However, almost 50% rarely used sunscreen while training, 27% frequently used sunscreen, and only 3% always used sunscreen. As many as 20% of the participants admitted they never used sunscreen.
Nearly one-third of the athletes (26%) reported previously having severe sunburns with blisters. Almost 10% reported a positive family history of melanoma and one reported positive personal history of melanoma.
Skin examinations revealed that nearly half of the participants (46%) had solar lentigines and 25% had atypical nevi, while two participants presented with actinically damaged skin and two participants with actinic keratoses.
The majority of the triathletes (57%) had less than 20 nevi on their skin, while only around 10% had between 50 and 100 nevi. No lesions that were suggestive of invasive skin cancer—non-melanoma skin cancer or melanoma—were identified.
“Despite the application of water-resistant sunscreen (SPF 25+), these triathletes showed sunburn on sun-exposed skin, which was most probably due to water exposure, sweating and friction,” the authors wrote.
While no invasive skin cancer was detected in the athletes, a significant number of participants presented with solar lentigines and a fair amount with atypical nevi, both considered risk factors for skin cancer.
Furthermore, a large proportion of participants had a history of severe blistering sunburns, which is not surprising given that 20% never use sunscreen.