Tennis stars are hit hard by the scorching Melbourne summer heat at this year’s Australian Open. With temperatures pushing 30 degrees and some matches scheduled for midday, it’s hard enough for the fans watching on the sidelines.
Athletes have over the years expressed concern and criticised organisers over guidelines surrounding the suspension of games during heat waves. In 2009 Novak Djokovic had to retire from a match against Andy Roddick due to heat exhaustion.
Serena Williams confirmed in an interview that the extreme weather had a hand in her performance at the Open in 2014; temperatures reached as high as 43.9 °C for four consecutive days. Some players reported severe fatigue, while others said they began to hallucinate.
Core body temperature rises, and dehydration kicks after extended exposure to high temperatures. Intense physical movements exacerbate these symptoms of exhaustion and fatigue.
While temperatures upwards of 40 °C are intense by any standards, some athletes like Roger Federer believe conditioning and targeted training can mitigate some stress; in an ESPN article, Andy Murray credits training in 32 °C Florida as a helpful strategy.
Heat and performance
“In tennis, the weather is a very important factor that can affect players who are not prepared properly,” says David Souto, lead tennis coach at Hong Kong Golf and Tennis Academy.
Tennis players aren’t the only ones dealing with extreme heat. The desert heat is expected to hit footballers hard during the FIFA World Cup Qatar 2022, so much that the games are pushed to the end of the year in hopes of cooler winter temperatures.
Hongkongers are well used to the city’s notorious year-round humidity and summers heat that pushes hear the high 30°C’s; athletes like Timothy Ho, rope-skipping world champion and recorder holder, take advantage of summer training to up their performance.
“Training outdoors during summer is definitely easier for warm-up. The body is already optimised, unlike during winter, where my body cools down pretty quickly after warm-up,” Ho says.
Science seems to support Ho’s experience. According to researchers, exposing the body to higher temperatures can “reduce the heat storage capacity and reduce exercise capacity in hot environments.”
While getting the body used to high temperatures during training and warm-up can be good, controlling the pre and post-match conditions is essential to performance.
“It is important to control the athlete's body temperature in the hours before the match in extreme climates. Spending time in the heat before playing is counterproductive, and being in a cold room with air conditioning 30 minutes before the match will not help either. By suddenly going out into the heat, the body will generate an adverse reaction to the cold-hot contrast,” says Souto.
Ho agrees that extended exposure can strain his performance. “I tend to get tired more quickly when I’m training in the heat.”
For some, however, heat compliments and is a part of the practice. Hot yoga, for instance, relies on high temperatures to detoxify, sharpen focus, boost agility and stamina. A 2010 study on heat acclimation seems to support this approach. A group of cyclists' aerobic exercise performance improved overall, even when in cooler conditions when they regularly apply heat acclimation to their training.
Dehydration and rehydration
One of the most immediate impacts heat exposure has on the body is dehydration. Souto advises staying hydrated to mitigate excessive sweating, which he reckons is more detrimental than anything else to performance to keep the body going.
“Scientific research shows that by losing two per cent of liquid, the athlete reduces his performance by 20 to 30 per cent. If dehydration reaches five per cent, the performance drops by half.”
Hydration should begin 24 hours before a match. But how do you know you’re dehydrated pre-match? Souto says one easy indicator is the good-ol’ urine colour. “If it has a dark tone, it means that the body does not have enough liquid. Ideally, the urine should be light in colour, almost transparent.”
As to the moments leading up to a match and during, the former pro has this advice: “Before matches, it is recommended to start drinking isotonic drinks, but maintaining a ratio of three to one, three sips of water for one isotonic. It is recommended to drink approximately one glass of water during matches every 20 minutes.”
And finally, humidity leads to a more significant loss of fluids. So in extreme humidity, players are advised to add extra salt to meals to help replenish salts lost during outdoor play.