A study has predicted which athletes will receive the highest amount of UV solar radiation at next year's summer Olympic games in Tokyo. It found that whoever is crowned winner of the women's singles tennis tournament will receive the most rays, followed by the gold medallist for men's golf, and the winner of the men's cycling road race. Athletes with fair skin who don't wear sun cream can expect considerable sunburn when competing in singles tennis, golf, the cycling road race, beach volleyball, hockey, rugby, the decathlon, the triathlon, football, softball and the 10 km marathon swim.
Thanks to global warming we are seeing record summertime temperatures in our cities. While this can be dangerous for the elderly, and people with health conditions, it can also be hazardous to professional athletes.
The study, published in the Taylor & Francis journal Temperature, found that this is especially true for tennis players, golf stars and cyclists, as they are often out for long periods in the hottest parts of the day. This puts these athletes at severe risk of sunburn, which itself is known to increase the risk of skin cancer.
"The winner of the women's singles tennis will have to compete in 6 rounds, many of which will be at peak midday," says the author of the study, Dr Nathan Downs, a Senior Lecturer in Mathematics at the University of Southern Queensland, Australia.
"Golfers must also compete in four daytime rounds, and the winner of the men's cycling road race can also expect to be exposed to sunlight for at least 6 hours, with other competitors being outside for even longer."
To calculate the total sun exposure that each gold medal winner of the 144 outdoor events will receive over the duration of the 2020 games, Dr Downs used satellite data on cloud cover, ozone and aerosol concentrations to create a model of the ambient UV environment that athletes will be exposed to in Tokyo. He then looked at what time of day the events are usually held at, and how long they tend to last.
Next Downs used footage of Rio 2016 to look at what type of clothing is usually worn by competitors, and whether they compete on grass, concrete, water or sand - as each of these surfaces reflect the sun's rays to differing extents. He also modelled the athlete's body posture, as this can affect what parts of the body are exposed to sunlight.
The results showed that the duration of events, and the time of day that they take place in are the most important factors influencing UV exposure, which is why tennis, golf and cycling stars are the most at risk.
However factors like clothing also play a huge role. Female tennis players only topped the league tables because male tennis stars tend to wear protective caps. Beach volleyball players' lack of clothing, coupled with the fact their matches take place on highly reflective sand also put them at considerable risk. On the other hand, the fact that golfers tend to wear long trousers and a cap stopped their sun exposure from being even higher.
"We were often amazed that for events like rowing or the 50 km walk, a good number of competitors in Rio chose not to wear a hat or cap," says Dr Nathan Downs. "Little things like this can make a difference, but competitive clothing that comfortably covers the greatest body surface area will have the most significant benefit."
According to Dr Downs, other measures that could help include making sure to schedule long events when the sun is lower down in the sky or at night.
"Events like the Marathon are purposefully scheduled to run early in the morning in order to keep the total sun exposure down, so this is something that could be considered for other events too. Other things that can be done include route alterations that make greater use of shade, or careful use of sunscreens to prevent unnecessary sunburn."
The study also recommends that the Olympic Committee adopt specific sun protection regulations and guidelines.