The first match of the men’s football World Cup kicked off in Qatar on 20 November, when the temperature was expected to be around 30 degC and humidity approaching 60%. When Qatar first won the bid to host the tournament 12 years ago, extreme heat was one of several concerns; since then, the average annual temperature in the country has risen by around 1degC. The 2022 tournament is the first to be held in November, to avoid Qatar’s hot summer. How will the footballers fare in this heat? What lessons can the tournament offer for sport in general?
The most important measure of heat and athletes’ health, and the reason for that, is the wetbulb globe temperature (WBGT). This combines heat, humidity, and other factors such as the angle of Sun and wind speed. High humidity makes it feel hotter. The human body’s cooling mechanism, which is a process of sweating to evaporate water off the skin, is less efficient when there is so much water in air. High WBGTs can lead to dangerously high core temperatures.
Although air-conditioning will reduce heat exposure for World Cup players, teams may still feel heat stress. The cooling effect of air-conditioning will be more noticeable for the spectators than for the players. This is because the cool air comes from the stands and the pitch side walls. Carolyn Broderick, a scientist at the University of New South Wales in Sydney (Australia), who is chief medical officer for Tennis Australia. She also serves as the medical director for the Australian Olympic team. She says that it is still cooler on the field than outside, but in a less drastic way.
Many stadiums have an open roof, so players can still be exposed to heat stress, according to Thijs Eijsvogels (an exercise physiologist at Radboud University Medical Centre in Nijmegen), the Netherlands. He says that the World Cup training areas are “just ordinary training grounds, without any air conditioning.”
Players have the ability to prepare their bodies if they have enough time. Eijsvogels helped to get Dutch athletes ready for another hot event: the Tokyo Olympic Games in 2020. Before the Olympics, he tested the athletes in controlled environments, at 16 degC and then in conditions that simulated the Tokyo summer climate. “We observed an average performance loss of 25%,” he says. His team experimented with heat during training to mitigate this. They found that the athletes performed better in hot conditions. Eijsvogels says, “We are tropical animals.” For football players from climates similar to those in northern Europe, heat exposure for 10-14 days is enough to become fully acclimatized, he says.
Researchers also experiment with ways to determine when an athlete is too hot and how to cool them down to safe levels. Ollie Jay, director of Heat and Health Research Incubator, University of Sydney, says, “The problem is not the hot environment. It’s the person.” Jay and Broderick have created a heat stress scale that can provide a simple measure for the risk of heat rises. The system has been used successfully in the Australian Open tennis tournament, Jay says, leading to one of the women’s semi-finals in 2019 being paused to allow the stadium to be covered and cooled.
Other interventions that have been found to be helpful include ice towels, cold water, or ice slurries to lower the body’s core temperatures. In tennis, Jay says, it is simple to include these mitigations at regular intervals, because the game has regular 90- or 120-second breaks. These breaks might be more difficult to engineer in football.
As global warming causes temperatures to soar, the question of how to maintain athletic performance in extreme heat becomes more urgent. FIFPRO, the professional football players’ union in Amsterdam, has called on the football industry to pay greater attention to the heat. It has been linked to climate change. It calls for greater player protection, including water breaks.
Amateur sports could be most affected by climate change, as they have less access to mitigation and acclimatization interventions than professional athletes, according to Eijsvogels.
Sport can continue in a changing environment with smart management, mitigation, and monitoring, says Jay. Jay says that if you have a risk management system that is well-designed and proven to work, and it’s properly implemented, you are actually increasing the safety of players.
This article is reproduced with permission and was first published on November 18 2022.