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Tennis Matches Are Heating Up, Literally. Here’s How the Court Became a Living Laboratory for Managing Extreme Temperatures
The sport’s hard-court surfaces can reach some 30 degrees hotter than the surrounding air. With elite players suffering heat illness on the world stage, athletes are following personalized cooling plans
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As I drew back my racket to rip a forehand down the line, it felt like my reaction time had slipped into slow motion and my legs were turning to Jell-O. I watched the ball drop into the net. Trying to understand how my one tennis weapon had become a weakness in a matter of minutes, I glanced at the thermometer. It read 98 degrees. After blowing through five packs of electrolytes in the dry Arizona heat in June, I flew back home to cool, coastal Maine with a headache that lasted for three days.
The heat-absorbing hard-court tennis surface can soar some 30 degrees higher than the air temperature around it. Playing in these conditions without balancing your water and electrolyte intake can become, in the sport’s terms, an ill-fated double fault.
The dangers of oppressive heat were in full view at the Cincinnati Open this month, when world No. 5 player Novak Djokovic collapsed mid-match, as the heat exacerbated a chronic health condition. The incident led to criticism about scheduling matches in peak heat. In July at the Memphis Classic, Ekaterina Alexandrova was wheeled off the court due to heat-related illness. Even on the cooler clay surface at the French Open in May, when a heat dome trapped hot air over the region, Jakub Menšík keeled over at the end of a five-set win, as fans left their scorching seats to crowd under the court sprinklers.
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Tennis is pushing athletes’ physiological limits in a rapidly warming world. In many ways, it’s the nature of the game—intense, quick sprints and powerful swings, followed by short changeover breaks on such a sizzling surface—that can quickly raise a player’s metabolic rate and make it very hard to cool down. For the past two decades, scientists have increasingly looked at a whole-body approach to managing heat on the court—one that goes beyond simply guzzling water. The hard-court surface, in a sense, has become a laboratory for heat stress management.
“Highly visible matches continue to show that elite athletes are not heat-proof,” says Babette Pluim, a leading expert in tennis and exercise medicine at the Amsterdam Collaboration on Health and Safety in Sports, adding that the governing bodies are responding. “Tennis is emerging as one of the first global sports to combine sport-specific physiological modeling, real-time environmental monitoring and structured rule changes to manage the limits of human heat dissipation.”
The risk of a hot tournament day—defined as over 82 degrees—has increased in all four Grand Slam tournament cities (New York, London, Paris and Melbourne, Australia) since 1970, according to a June report by the nonprofit Climate Central. For the U.S. Open in Queens, New York, which began this year on August 23, that risk has risen from 49 percent in the 1970s to 67 percent.
Greenhouse gases are warming the planet, and by extension, changing the rules of court. After seven match retirements from the October 2025 Shanghai Masters, followed by fierce disapproval, the Association of Tennis Professionals (ATP) became one of the last major tennis governing bodies to implement rules for play in extreme heat, aligning with guidelines used by the Women’s Tennis Association (WTA) and at the Grand Slams. They now allow players a ten-minute cooling break if temperatures exceed 86 degrees and suspend play above 90 degrees, measured by the Wet-Bulb Globe Temperature (WBGT), a metric for heat stress in direct sunlight linked to temperature, humidity, wind speed, cloud cover and the angle of the sun. In 2023, the U.S. Open began allowing the stadium roof to be closed in extreme heat.
Overheating in tennis is caused by a combination of factors, including prolonged exertion, direct sun exposure, limited cooling opportunities and matches of unpredictable duration that can last up to five hours.
“There is a greater appreciation of the challenges prompted by heat, and an effort to provide guidelines and adopt procedures to offset [them],” says Michael Bergeron, a clinical and scientific adviser in sport sciences and medicine and performance health for the WTA, which first implemented extreme weather rules in 1992.
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Taking the heat
On an oppressively hot day, blood vessels widen, sending warm blood toward the skin so that the heat can escape and cool you down. But when it’s dry out, an athlete may not be able to drink fast enough to replenish the fluids lost as sweat. On comes rapid dehydration, which reduces blood flow to organs, increases heart rate, weakens concentration and slows down the body. At higher altitudes, dehydration is apt to happen faster.
“Headache, nausea, dizziness and impaired coordination may develop,” explains Pluim, who is also chief medical officer of the Royal Netherlands Lawn Tennis Association and a researcher at the University of Pretoria in South Africa. Extreme cases can cause exertional heat stroke, which she says “involves neurological dysfunction—such as confusion, collapse or unconsciousness—with a very high core temperature, generally around or above 104 degrees.” If overlooked, exertional heat stroke can lead to multiple organ failure, cognitive disability or death.
Losing even a fraction of a percent of the body’s water may reduce grip strength and attention, a July study found, while broader research indicates dehydration leads to a slower reaction time and speed, poorer shot selection and impaired coordination and decision making. At this year’s French Open, Australian player Daria Kasatkina said temperatures often take a toll on an athlete’s mental game, calling loss of focus from heat a whole new battle on the court.
Personalized cooling plans
While scientists have shown for decades that individuals tolerate heat differently, extreme heatwaves in the 2010s brought a shift toward highly customized cooling plans in tennis. By 2019, the Australian Open introduced a personalized, evidence-based system called the Heat Stress Scale to measure and suspend play based on real-time environmental data and a player’s own health and physiological limits.
Did you know? Extreme heat at the 2014 Australian Open
Severe heat forced a suspension of play at the high-profile 2014 Australian Open, where temperatures surpassed 109 degrees Fahrenheit. Nine players retired or withdrew from matches in the first round of the singles tournaments.
During training, many elite players are increasingly taking advantage of wearable technology to track sleep, heart rate response, glucose levels, hydration, body and skin temperature, sweat rate and body mass. Others are experimenting in clinical trials with swallowing electronic sensors known as core temperature capsules that transmit internal body temperature to map thermal strain.
Even recreational tennis, pickleball and padel players should check the WBGT app and be aware of their own threshold for heat, including factors like age, ability to acclimatize, sweat rate, body size, sleep, medications, illnesses, activity load and duration of play.
“Research has demonstrated that hydration alone cannot prevent exertional heat illness,” says Kathleen Stroia, senior vice president of performance health for the WTA. “Effective heat management requires a comprehensive strategy.” That includes heat acclimatization, hydration, electrolyte replacement, nutritional planning, cooling strategies, recovery and medical preparedness.
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Beyond a player’s own heat management regimen, climate change adaptation can be seen through ongoing shifts to the design of tennis stadiums, from more retractable roofs and shading to the testing of new hard-court surfaces. One such surface, called the Laykold Chill technology, is made from microscopic components that absorb heat and slow the rise of the court’s temperature. It became the official surface of the Mubadala Abu Dhabi Open, after debuting in 2024 and achieving a 30 percent temperature reduction. Another new material, called CoolTop, has a layer of infrared-reflective pigments to absorb less solar energy. It now coats courts at Florida’s U.S. Open Pickleball Championships and is the preferred surface of Pickleball Australia, reportedly reducing the court heat from about 126 degrees to 100.
Keeping it cool during a match
Staying cool on the court starts by scheduling play outside peak heat—and arriving hydrated. To fully absorb fluids, the United States Tennis Association (USTA), tennis’ national governing body, recommends drinking a 12- to 16-ounce glass of water after waking up on competition day, followed by another 12 to 16 ounces of water roughly an hour before playing and 8 ounces of water ten minutes before stepping onto the court.
Pre-cooling techniques can lower the body’s heat storage capacity before performance drops. At this year’s Australian Open in January, world No. 1 player Jannik Sinner developed significant cramping in the heat. During his June training for Wimbledon, Sinner was spotted wearing a cooling vest before playing. The USTA suggests wearing these for 15 minutes roughly one hour before hitting, and some players opt for a quick, cold shower.
To reduce dehydration and heat strain during hot matches, the pros follow individualized routines based on sweat changes. On every 90- or 120-second changeover, they might drink up to 14 ounces of water and electrolytes and suck on ice chips in the shade. They’re pouring water over their heads and applying cold, wet towels or ice bags to easy-to-cool areas with temperature-sensitive nerve endings, like the neck, head and face.
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“In our studies, ice towels and wetting the skin in front of a fan reduced core temperature by approximately [1 degree] compared with drinking cold water alone in simulated Australian Open conditions,” explains Pluim.
Sports scientists recommend cooling the palms of your hands, which contain blood vessels that help transfer heat, to potentially reduce thermal discomfort and perceived exertion, even if it doesn’t rapidly cool your core body temperature.
For cooldown and recovery, players should keep drinking water and can lower body temperature by resting in the shade or air conditioning, rehydrating, replenishing electrolytes and eating protein and nutrient-dense carbohydrates.
Athletes, when advised, are chilling the bloodstream with a cold bath or shower, which constricts blood vessels to slow metabolic activity. For regular post-match recovery, this may help lower body temperature and reduce muscle soreness and fatigue, though Pluim doesn’t recommend using it after every session. In cases of suspected exertional heat stroke, athetes may use cold-water immersion with medical supervision to rapidly reduce core temperature and the risk of organ damage. In fact, in 2026, ATP began requiring ice baths be available to tournament players in recovery rooms.
As pickleball and padel continue to sweep through the world and tennis participation surges, knowing how to stay cool on the court has become non-negotiable. So the next time you’re out on your neighborhood court and notice your concentration declining or a headache coming on, you might want to do yourself a favor and cut your match short.
“I recommend playing earlier and for less time, allowing more recovery between hot days and using active cooling during breaks,” advises Pluim.