Thermo Tokyo Beat the HeatIn the summer of 2021, the Tokyo Olympic and Paralympic Games will be held in Tokyo. At that time, the ambient temperature will be above 30°C and the humidity can reach 75%. These circumstances will be the most challenging ever observed during the Olympic and Paralympic Games. read more
Thermo Tokyo Beat the Heat
In the summer of 2021, the Tokyo Olympic and Paralympic Games will be held in Tokyo. At that time, the ambient temperature will be above 30°C and the humidity can reach 75%. These circumstances will be the most challenging ever observed during the Olympic and Paralympic Games.
In the Thermo Tokyo project, an interdisciplinary consortium consisting of representatives of the Radboudumc, the HAN University of Applied Sciences, VU University Amsterdam, Delft University of Technology, and NOC*NSF, work together to beat the heat and to be a step ahead of the competition during the Tokyo Olympics. To achieve this goal, several studies have been carried out.
Between November 2018 and February 2020, 130 Dutch elite athletes performed personalized exercise tests in the climate chamber at Papendal. These tests were used to determine how heat impacts their physiological responses and performance capacities during exercise in the heat. In two other studies, we investigated how acclimatization can be performed best, which cooling strategies are most effective, and how cooling strategies can be optimized for specific sports.
Based on these scientific insights, countermeasures such as heat acclimatiztion and cooling interventions have been personalized, and by this, the Thermo Tokyo consortium contributes to safe and maximum exercise performance by TeamNL athletes during the Tokyo 2021 Olympic and Paralympic Games.
The rationale and design of the Thermo Tokyo study have been published in the scientific journal Temperature.
Header photo by Guus Dubbelman.
In the media
- Kenniscentrum suiker & voeding (in Dutch): september 2021 - Verslaan van de klimaatomstandigheden tijdens Olympische Spelen.
- RTL Nieuws (in Dutch): 24 juli 2021 - Voorbereiding op heetste Spelen ooit: trainen in de hittekamer.
- Omroep Gelderland (in Dutch): 23 juli 2021 - 'Dit zijn de heetste Spelen ooit', sporters krijgen hulp met hitte.
- NU.nl (in Dutch): 22 juli 2021 - Koelvesten en ijsbaden: Nederlanders klaar voor warmste Spelen ooit.
- Radboudumc (in Dutch): 22 juli 2021 - Hoe zijn de Nederlandse Olympiërs voorbereid op de hitte en luchtvochtigheid van Tokio?
- NRC (in Dutch): 20 juli 2021 - In Tokio is het eigenlijk te warm om te sporten
- Het Nederlandse Watersportverbond (in Dutch): 15 juli 2021 - Hoe gaan de zeilers van TeamAllianz om met de hoge luchtvochtigheid in Japan?
- Trouw (in Dutch): 29 mei 2021- Met koelvesten en klimaatkamers gaan Olympische sporters de hitte van Tokyo te lijf (Also available in PDF).
- NPO 1 (in Dutch) : 1 maart 2020 - NOS Journaal (vanaf minuut 13).
- NPO 1 (in Dutch) : 1 maart 2020 - NOS Jeugdjournaal: Sporters trainen in hitte-kamer voor Olympische Spelen.
- NPO Radio 1 (in Dutch) : 29 februari 2020 - NOS Radio 1 journaal (vanaf minuut 50).
- EenVandaag (in Dutch) : 20 februari 2020 - Dankzij dit onderzoek kunnen sporters én supporters zich goed voorbereiden op de hitte in Olympisch Tokio.
- NPO Radio 1 (in Dutch) : 18 februari 2020 - Radio EenVandaag (vanaf minuut 37).
- VOX (in Dutch) : 29 januari 2020 - Onderzoek: hoe wapent olympische supporter zich tegen Japanse hitte?
- De Gelderlander (in Dutch) : 27 januari 2020 - Olympische sporters trotseren op Papendal vochtige hitte om te vlammen in Tokio: ‘Niet eerder Spelen in zo’n uitdagend klimaat’.
- Omroep Gelderland (in Dutch) : 15 januari 2020 - Is deze Nijmeegse klimaatkamer het geheime wapen voor olympisch succes?
- Hockey.nl (in Dutch) : 25 november 2019 - Oranje Heren tot het gaatje bij klimaattest op Papendal.
- TeamNL (in Dutch) : 13 november 2019 - Diede de Groot ziet af in de klimaatkamer.
- Hart van Nederland (in Dutch) : 28 oktober 2019 - Topsporters bereiden zich voor op extreme hitte Paralympische en Olympische Spelen in Tokio.
- NPO 2 (in Dutch) : 23 april 2019 - Sportlab Sedoc: Pieken (vanaf minuut 16).
- SportKnowHowXL (in Dutch) : 19 april 2018 - ‘Thermo Tokio’: olympische kampioenen in strijd met de hitte.
- De Volkskrant (in Dutch) : 4 januari 2019 - In de klimaatkamer van Papendal bereiden sporters zich voor op de temperaturen in Tokio.
The challenging climate during Tokyo’s summer was the reason to initiate this project. But what makes this climate so harsh for participating athletes?
During exercise, 80% of the energy is converted into heat. This causes the body temperature to rise. The warmer and more humid the environment, the more difficult it is to dissipate heat. The most effective way to dissipate heat is via evaporation of sweat. However, when the humidity is high, sweat evaporates less easily. As a result, the heat loss to the environment is limited and the exercise-induced increases in body temperature are larger than normal.
On an average summer day in Tokyo, the ambient temperature is around 30°C and the humidity can reach 75%. The combination of high ambient temperatures and high humidity during the Tokyo Olympic and Paralympic Games will result in very challenging circumstances.
During exercise and sports, the heat production in the body increases causing the body temperature to rise. Progressive increases in body temperature may cause substantial reductions in exercise performance and place athletes at a higher risk of developing heat-related illnesses.
Between November 2018 and February 2020, personalized heat profiles were obtained in 130 Dutch elite athletes. These profiles were based on two personalized exercise tests in the climate chamber at Papendal. Each athlete performed one exercise test in a cooler climate (15°C and normal humidity) and one exercise test in a Tokyo climate (32°C and high humidity). During both tests, extensive physiological measurements were performed such as monitoring of heart rate, body temperature, skin temperature, and sweat loss. These measurements allowed us to assess the effect of the Tokyo climate on exercise performance capacity and individual physiological responses.
The climate chamber measurements demonstrated that the Tokyo climate has a major impact on the exercise capacity of elite athletes. The average loss of performance was over 25% and the average maximum body temperature was 38.9°C. Surprisingly, the way athletes react to exercising in the heat largely varied. For example, the maximum body temperature varied between 37.6 and 40.4°C, while the degree of performance loss varied between 0 and 48%. These results emphasize that it is impossible to offer a ‘one-size-fits-all’ heat mitigation strategy to elite athletes and underline the importance to determine the individual’s needs for specific countermeasures.
Therefore, in collaboration with NOC*NSF and the medical staff of various sports associations, we worked hard to determined the individual’s need for heat acclimation, cooling interventions, and a hydration plan. Based on these insights personalized individual plans were developed. By this, the Thermo Tokyo consortium contributes to safe and maximum exercise performance by TeamNL athletes during the Tokyo 2021 Olympic and Paralympic Games.
Picture by Guus Dubbelman.
The human body is perfectly capable of adapting to a hot and humid climate. However, it takes 10 to 14 days for the body to fully adapt. When fully acclimatized, the resting body temperature is lower, blood volume is increased, the athlete starts sweating earlier, and the resting heart rate is lower. With these physiological adaptations, an athlete may improve his performance in the heat by 30%.
In the Thermo Tokyo project, we investigated how athletes can adapt to the heat (acclimatization or acclimation (when performed in laboratory)) in the best way. We did this by determining the speed and degree of physiological adaptations and by exploring new re-acclimatization strategies. Re-acclimatization strategies have good potential as it is not possible for every athlete to travel to Tokyo to fully adapt.
We found that the speed and degree of adaptations differ between individuals. It was remarkable that individuals with higher weight sweat more, while athletes with a lower weight show a greater drop in heart rate. After a 10-day acclimatization period, the physiological adaptations remain for several weeks, even when the body is no longer exposed to the heat. However, the sweating capacity seems to decrease faster. But, with a 5-day re-acclimatization, this maximum sweating capacity is easily regained. The effect of a 10-day acclimatization period on performance is great, but the effect fades away when the body is no longer exposed to the heat. In addition, the positive effect on performance cannot be regained by conducting a short 5-day re-acclimatization period only.
These results show that it is very important to adapt to the hot and humid Tokyo climate in preparation for the Tokyo 2021 Olympic and Paralympic Games. Heat exposure helps induce physiological adaptations which contribute to better temperature regulation and help to alleviate the heat-induced reductions in exercise performance. Since the time course of adaptations is different across individuals, it is important to plan and monitor the speed and degree of acclimatization at an individual level.
Based on these scientific insights, we have worked hard in collaboration with NOC*NSF and the medical staff of various sports associations to develop individual heat acclimatization programs. By this, the Thermo Tokyo consortium contributes to safe and maximum exercise performance by TeamNL athletes during the Tokyo 2021 Olympic and Paralympic Games.