Extreme levels of heat and humidity could endanger athlete health at the Tokyo Olympics

According to a new study, high levels of heat and humidity driven by climate change pose significant threats to the health of competitors at the Tokyo Olympics to be held in July.

The Tokyo Olympics, which was postponed last year due to the global COVID-19 pandemic, is now scheduled for this summer. While the pandemic still looms large with several countries struggling to suppress new infections and mutations, a new study has thrown the spotlight on the heightened risks of climate change to athletes competing in arguably the largest sporting event in the world.

The study titled, ‘Rings of Fire: How heat could impact the 2021 Tokyo Olympics’, is backed by leading athletes, the British Association for Sustainability in Sport (BASIS) and scientists from the Priestley International Centre for Climate at Leeds University and Portsmouth University’s Extreme Environment Laboratory. It comprises inputs from leading triathletes, rowers, tennis players, marathon runners and scientists advising athletes how to cope in extreme conditions.

Extreme climate events in Tokyo

Tokyo, the host city for the Olympics, has seen a rise in its mean annual temperature by 2.86-degree Celsius since 1900- more than three times as fast as the world’s average, the study states.

According to the study, changes in land use and urbanisation in Tokyo have led to enhancement of the urban heat island (UHI) effect. UHI traps heat in the surface and impacts thermoregulation, “effectively impairing a city’s ability to breathe,” the study notes.

The authors point out that since 1900, the maximum daily temperature in Tokyo has exceeded 35 degree Celsius due to which it has more days each year. They also mention the links between climate change and the brutal Tokyo heatwave in 2018, which led to over 1,000 deaths. Heatwaves hit Japan again in the summers of 2019 and 2020, leaving thousands in hospital as temperatures across the country topped 39°C.

Analysing the positive trends, the study found that Tokyo might witness even higher daily temperatures as a result of increasing global levels of carbon dioxide in the atmosphere.

How high levels of heat and humidity affect the players?

A hot or humid environment puts the performance and health of spectators, officials and athletes at risk, according to Mike Tipton, Professor at the University of Portsmouth.

According to him, cool and dry environments at around 11-degree Celsius is the best-suited condition for humans to perform continuous exercise. Increases in temperature and humidity, on the other hand, both cognitive and physical performance of the athletes deteriorate, to the point where health is put at risk.

The potential impact of heat on various sports is analysed by the study. For example, in road cycling, softened tarmac could lead to crashes due to long periods of time exposed to radiant light. Additionally, in triathlon, increased levels of heat slow the performance time.

“The differences of 1-2 degrees on a race day will have a major impact on whether the event is safe to run,” said Ben Bright, head coach at the British Triathlon Federation.

Not only athletes but also elevated heat levels cause discomfort for spectators and staff in various sport events.

As a result, in the Tokyo Olympics, the marathon and cycling events have already been moved to cooler climes, but other sports may face safety checks before they proceed in July, the study notes.

“I think we’re certainly approaching a danger zone… it’s a horrible moment when you see athletes cross the line, their bodies fling back in total exhaustion, and then not rise up,” said elite British rower Mel Wilson at the study’s release.

Additional challenges to Paralympics

According to the study, extreme heat events could pose additional challenges to Paralympic athletes due to their impairments. Impairments are often associated with symptoms and thermoregulatory challenges specific not only to that impairment but also to the individual.

Extreme heat events would have a major impact on athletes with a spinal cord injury as they are unable to thermoregulate efficiently below their damaged organ, while athletes with prosthetic limbs might face swelling and increased sweat due to an exacerbation in heat, the study notes.

Keeping in mind the potential extreme conditions in Tokyo, the study recommends that support staff should consider the impact on Paralympic athletes, not only during the performance but while living and thriving in the environment for the duration of the time that they are in the country.

The way ahead

Extreme heat has created a lot of hurdles for athletes to compete over the years. However, if the current heat trend continues, there would be more repercussions for athletes, referees and spectators, impacting the health, performance and overall sporting spectacle.

To counter the effect of extreme climatic events, some ruling bodies and federations are making positive strides. The International Olympic Committee (IOC) has also aligned with the Paris Agreement, setting a target to reduce their greenhouse gas emissions by 45% by 2030.

The study recommends focus on pre-event athlete preparation, acclimatization strategies and development of more shaded areas for them to rest and prepare for events. To monitor heat and body temperatures, it advocated the use of enhanced technologies.

“It’s time that organisers of major global sporting events made climate impacts, as well as environmental sustainability, a core factor in deciding where and how they should be hosted. As this report shows, we can’t continue to treat climate change as a marginal concern. The risk to athletes and spectators is a central concern,” said Russell Seymour, the CEO of BASIS.

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