FIFA hydration breaks have sparked criticism from different groups. But what do they actually do?

“When we look at the three-minute hydration breaks, we're really looking at this as a way to mitigate anything that could potentially lead to an incident or an emergency,” said Joshua L. DeVincenzo with Columbia University’s National Center for Disaster Preparedness.

FIFA's mandatory breaks, regardless of temperatures

FIFA said the mandatory breaks are to “ensure equal conditions for all teams, in all matches,” and the rules draw upon the experiences of past tournaments, including the FIFA Club World Cup in the U.S. last summer when temperatures soared.

Some coaches said the breaks make sense when temperatures are extreme, but they questioned whether they were necessary at every match. The pauses have also been criticized for interrupting the spectacle for fans, with broadcasters cutting to commercials.

Mexico coach Javier Aguirre said they're making the most of the hydration breaks.

“You can’t get on the field but the players can come near you while drinking water and we can give them instructions,” he said. “We take advantage to try to correct something during the game, it’s something good for the coaches.”

Even highly-trained, elite athletes can get heat stress

Athletes pushing themselves physically in hot and humid conditions risk getting what's called exertional heat illness. It happens when the body gets too hot and is accompanied by significant strain on the heart, nerves, muscles and central nervous systems.

Symptoms include muscle cramps, extreme fatigue, impaired performance, headache, irritability, nausea, dizziness, cramping and dehydration.

When internal body temperature exceeds 105 F (40.5 C), athletes might feel confused, aggressive or lose consciousness, said Yuri Hosokawa with the Faculty of Sport Sciences in Japan’s Waseda University, in an email, “all of which are characteristic signs of exertional heat stroke and require immediate medical attention.” She co-signed a letter to FIFA in May urging stricter heat guidelines for player safety, including that cooling breaks be at least six minutes.

Exertional heat stroke is among the leading causes of death in athletes.

Dehydration also exacerbates the risk. Athletes in the heat can sweat 1 to 2 liters (50 to 67 ounces) an hour, and most drink less liquids than they expel. Losing as little as 2% of one's body weight to dehydration can impair physical performance.

Ryan Calsbeek, professor of biological sciences at Dartmouth College, said the human body performs better when it’s warmer, but there’s a critical threshold above which that improvement in performance not only stops, but precipitously drops off.

“Your body starts to really fall apart, you lose the ability to cool off fast enough,” he said. “And the physiological mechanisms just break down.” That happens when the wet bulb globe temperature, which includes temperature, humidity, cloud cover and wind, reads above about 95 F (35 C), though some people will be more heat tolerant.

The increased confusion from extreme heat could impact an athlete’s ability to make strategic decisions, he said.

“It’s these marginal differences in performance that I think can determine the outcome of a match,” Calsbeek said. “If you have individuals that do better in extreme conditions, whether it’s extreme heat or high altitude or whatever the case may be, those small differences could play a critical, pivotal role in determining the outcome.”

Hydration breaks should be longer, some experts say

The three-minute mandatory hydration breaks are meant to protect players, and referees, from extreme heat illness and help them maintain their physical performance.

Players can cool off and replenish lost water and salt from sweating.

That could mean putting wet, cold towels on parts of a player's body. If done well, that could reduce their body temperature by about 0.22 F (0.12 C) per minute, said Douglas Casa, CEO of the University of Connecticut’s Korey Stringer Institute who also co-signed the letter.

“Some people can tolerate a little more fluids comfortably and then do intense exercise. Some people can’t because it sloshes around in their stomach and they don’t feel super comfortable, so they might not drink as much in such a short period of time,” he added.

In a 2024 study, researchers found that three minutes lowered athletes' core temperature by about 0.72 F (0.4 C) during simulated soccer running in a heat chamber. But this happened in ideal conditions where they drank 350 to 400 milliliters of cold water and draped a cold towel on their shoulders.

Draping ice towels over a player's shoulders can be helpful, but only if they rehydrate as well, said Julien Périard in an email, a study co-author and director of the University of Canberra Research Institute for Sport and Exercise who also signed the letter.

That’s why it’s important the three minutes be well planned, but “even in ideal settings, the breaks can slightly help but will not eliminate the risk of heat illness in response to a rise in core temperature,” he said.

Casa said time dictates the volume of impact, whether from fluid or cooling.

How much time a player needs to recover also varies. “Depending on your body, you might need more or less time. But those kinds of breaks are crucial so that your body isn’t just being forced to keep trying to play catch up... to keep trying to cool you down without any kind of rest or a break,” said Bharat Venkat, director of the Heat Lab at the University of California, Los Angeles.

As our planet gets hotter, mandating hydration breaks and changing where, when and how sports are played will be necessary.

“No matter what sport you play, there’s going to be adjustments that have to be made in the face of climate change, ” he said.

Tales Azzoni contributed from Guadalajara, Mexico.

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