At the Olympics, Heat Can Raise the Danger Bar of Competitions

Athletes from more than 200 countries have convened in Paris for the Olympic Games.

But looming over it is the memory of the last summer Olympics in 2021, the hottest on record. Forced to compete in temperatures regularly above 92 degrees Fahrenheit, athletes from different sports buckled under Tokyo’s unusually high summer temperatures. Marathoners vomited or fainted minutes after crossing the finish line (if they were able to finish at all). Tennis players paused mid-match as they struggled against heat exhaustion.   

In Paris, forecasts for the upcoming weeks show temperatures around 70 to 80 degrees Fahrenheit, but experts fear that a heat wave blanketing parts of southern Europe could eventually creep into the City of Lights. 

Climate-fueled warming is pushing athletes to change their training conditions, while event organizers adopt new rules and update facilities to prevent heat-related illness. However, as the thermostat continues to inch up, some experts say we must rethink the Olympics altogether. 

Burning up Before the Finish Line: During the Tokyo Olympics in 2021, Spanish tennis player Paula Badosa had just finished her first set against Czech competitor Marketa Vondrousova in the grueling July heat when she took an extended medical time-out.

Moments later, Badosa was pushed off the court in a wheelchair by physicians, forfeiting the match to seek more extensive medical treatment. The athlete later revealed she had suffered heatstroke. 

“It’s a shame to end my participation in this way,” Badosa told Reuters. “It’s been a tough ask since day one, we tried to adapt as best we could, but today my body hasn’t held up as it needed to.”

Despite being in peak physical condition, Olympic athletes regularly push their bodies to the limit—a point that is met much faster during extreme heat. When you are active, your muscles require a steady supply of oxygen from the blood, which also acts as a coolant to offload excess heat. But outdoor heat can push you even harder, as blood flows closer to the skin and high external temperatures and increased humidity can disrupt the body’s ability to cool itself down through sweating. 

Compounding the problem, individuals lose roughly 1 liter of water from sweating every hour while exercising in high heat, which can eventually lead to dehydration, according to Mike Tipton, a professor of physiology at the University of Portsmouth in England. He told me that frequent water breaks help, but even this strategy can fall flat in scorching conditions because there is a limit to how much fluid the body can absorb from the gut. 

“Historically, the athletes were worried about training and nutrition. And they didn’t really pay much attention to heat,” Tipton said. “If you get your training wrong, and you get your nutrition wrong, well, it will have an impact on your performance, but it doesn’t threaten your life. And yet, if you get your temperature regulation wrong, you’ve got a chance of dying.” 

In partnership with the British Association for Sustainable Sport, Tipton and other researchers published a report in June outlining the slew of ways heat can put athletes from different sports at risk during the Summer Olympics. The report includes a number of firsthand perspectives from Olympic competitors around the world, including British marathon swimmer Amber Keegan, field hockey player Hugo Inglis from New Zealand and U.S. track and field competitor Sam Mattis—all of whom expressed heat-related health concerns. 

Along with stressing major risks like heat stroke or even death, the report points out several inconspicuous ways that higher temperatures during the Olympics can affect performance. For example, a pole vaulter bronze medalist discussed how increased sweat interferes with her grip in competition.

Athletic Adaptation: Researchers recently analyzed the effectiveness of different heat protection policies from the 32 governing bodies that manage the rules and regulations for each sport at the Paris Olympics. These policies, which differ by sport, can include increasing the frequency of water breaks or even postponing matches if the temperature reaches a certain point. 

The researchers found that 15 sports have a high risk of heat stress, including cycling, field hockey and tennis. Several of these sports lack effective policies, and none use metrics that comprehensively reflect the thermal strain endured by athletes based on their metabolic heat production and their level of acclimation to high temperatures, according to the study. 

In many cases, Olympic competitors and their trainers are taking matters into their own hands to beat the heat. In the weeks leading up to the competition, many athletes will exercise in heated rooms or tents for more than an hour while training each day to help their bodies adjust to the high temperatures they may experience. 

This process—known as acclimatization—can induce small changes in the body that help people better withstand the heat, including increased sweating efficiency, stabilization of blood circulation and increased blood flow to the skin. (I recently wrote about why heat acclimatization is crucial for tourists traveling to warm areas, if you’d like to read more.) 

At a physiological level, “the most important thing you can do is get people acclimatized,” Tipton said. During a match or race, competitors will often use ice towels, frozen water balloons and cool fluids to rapidly decrease their body temperatures. Some even use high-tech equipment such as wearable heat sensors or inflatable ice pools to avoid heat-related illness, Bloomberg reports. 

However, as journalist Shi En Kim points out in an article for National Geographic, athletes from low-income countries may not have the financial means to support extensive heat training or adequate air conditioning for recovery. And competitors aren’t the only ones exposed to heat during the games; spectators and referees also face heat-related health risks at sporting events, experts say. 

Climate impacts are increasingly top of mind for many sporting event coordinators. Paris politicians have committed to halving the emissions from this year’s summer Olympics when compared to the London 2012 and Rio 2016 average. 

While these types of efforts could help slow global warming down the line, protecting athletes from heat is crucial right now, Tipton said. He added that heat is also putting the Winter Olympics at risk—less from a health perspective and more because warming is causing snow shortages in many historically cold regions. 

With all this in mind, some experts have called for a full-scale shift in the timing of Summer and Winter Olympics, which may have to change their names if that comes to fruition. 

More Top Climate News 

In April, the Biden administration finalized a set of regulations requiring power plants to cap their emissions. While environmentalists lauded the ruling, Republican-led states and utilities almost immediately filed lawsuits against it. 

On Tuesday, a contingent of 25 Republican-led states sent a petition to the Supreme Court to stall the federal smokestack rule until their case plays out, The Hill reports. Though it remains to be seen whether the court will take up the petition, the states argued that the ruling is “really a backdoor avenue to forcing coal plants out of existence—a major question that no clear congressional authority permits.”

Meanwhile, Monday broke the record for the hottest day ever recorded on Earth. Average global surface air temperatures climbed to 62.87 degrees Fahrenheit, narrowly beating the previous record, which was set on … Sunday. 

“We are in an age where weather and climate records are frequently stretched beyond our tolerance levels, resulting in insurmountable loss of lives and livelihoods,” Roxy Mathew Koll, a climate scientist at the Indian Institute of Tropical Meteorology, told The Associated Press. 

In other news, wildfire smoke from the Western U.S. and Canada has drifted into the Northeast, The New York Times reports. The haze could negatively affect air quality in many coastal areas throughout New Jersey, New York and parts of Maine. It’s crucial to find efficient ventilation during these events to avoid negative health impacts. However, wildfire smoke can permeate indoors, too—a phenomenon I wrote about in May. 

Airlines across the U.S. have had a rough past few months following tech outages and system failures. Now, extreme heat is bursting soda cans on Southwest Airlines flights, injuring about 20 flight attendants, CBS News reports. The company says it is taking steps to address the issue, such as stocking fewer cans on provisioning trucks and placing carbonated beverages in coolers, particularly in hotter locations such as Austin and Las Vegas. 

Moving from the sky to the ocean: A new analysis found cocaine in the bodies of sharks swimming off Brazil. The researchers dissected 13 sharks captured between 2021 and 2023, finding evidence of chronic exposure. The scientists believe the drug is entering the ocean through waste and runoff from cocaine refineries into the sewage system. Though its impacts are still being studied, the researchers told National Geographic that negative health effects are “probable.” 

Also in Brazil, a federal court paused a project to pave a dirt highway from the city of Manaus to other areas, citing its potential contributions to climate change, The Associated Press reports. Half of the highway is currently paved, and the project would help complete the other half, currently impassable during the rainy season. However, deforestation has spiked in the area in recent years, and the judge said the road project failed to outline a plan to prevent more tree cutting when the road is finished and individuals have access to new regions.