News items How are the Dutch Olympians prepared for the heat and humidity of Tokyo
22 July 2021

The Olympic Games will take place in extreme weather conditions, which increases the risk for performance loss and the development of heat related illnesses. Dutch Olympians of TeamNL have prepared for these challenging conditions based on a personal acclimation and cooling advice after participation in a study led by researchers from Radboud university medical center.

It will be hot in Tokyo during the Olympics in the coming weeks. Extremely hot. The expected temperature is 32 degrees Celsius on average, and the humidity is over 75%. Not ideal conditions for elite athletes who have spent five years of training to deliver their best possible exercise performance. The International Olympic Committee is doing everything possible to make the conditions as favorable as possible, such as rescheduling races to the early morning, and applying air conditioning and water spraying in and around the stadiums.

But what can athletes do themselves to be as prepared as possible at the start? This question was posed by scientists from Radboud university medical center in collaboration with sports organization NOC*NSF, among others. They wanted to know how TeamNL athletes respond to the extremely hot conditions. What is needed to deliver an optimal exercise performance without increasing the risk to develop heat related illnesses? For this purpose, research project “Thermo Tokyo: Beat the Heat” was initiated in 2018.

Olympic and Paralympic athletes in the climate chamber

130 Olympic and Paralympic athletes participated in this study, performing two exercise tests in the climate chamber at the national Olympic training center. The first exercise test was held in Dutch conditions and the second test in simulated heat of Tokyo. Project leader Thijs Eijsvogels: "We measured the increase in core temperature and kept track of how long it took for them to become exhausted. Based on this, each athlete received a personal heat profile and a personalized advice on how to prepare for the expected heat at the Tokyo Olympics." With this information, the athletes, their trainers and medical supervisors were given the opportunity to prepare for the heat in the best possible way.

Getting used to the heat longer, cooling vests and slush puppies

The initial results of the study show that there is a lot of variation among the athletes. "This shows the importance of an individual approach in preparing for the Olympics. Every athlete has their own heat profile, so a one size fits all approach cannot be applied," said Yannick de Korte, as PhD student associated with the Thermo Tokyo project.

For example, athletes whose performance decreases significantly in the heat benefit from a longer heat acclimation or acclimatization period in which they get accustomed to the heat and beneficial physiological adaptations take place. Alternatively, an athlete with extreme exercise-induced elevations of core temperature rises should place more emphasis on cooling solutions before and, where possible, during exercise.

Thermophysiologist Coen Bongers: "Such cooling strategies can be done by the cooling vests that have been specifically developed for this purpose, and of course by drinking cold water or ice slush." Nevertheless, it is important to note that all TeamNL athletes should apply both acclimatization and cooling solutions, as marginal gains help to achieve that ultimate sports performance.

Video Thermo Tokyo: Beat the Heat

In this video physiologist Thijs Eijsvogels explains the project. Football player Renate Jansen takes the exercise test.


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