At the FIFA World Cup, players must overcome more than just their opponents’ defenses and tactical challenges. In this year’s tournament across the United States, Canada, and Mexico, one of the greatest challenges will be the environmental conditions – from the climate in Canada, which is relatively familiar to many Europeans, to the intense heat in Mexico and the southern states of the U.S. In some host cities, air temperatures may exceed 35-40°C (95-104°F), while additional factors such as high altitude and air pollution will place even greater demands on athletes’ bodies.
Professor Marius Brazaitis of the Sport Science and Innovation Institute at the Lithuanian Sports University (LSU) emphasizes that some of the most difficult conditions await players in Mexico.
“Mexico City is located more than 2,200 meters above sea level, meaning the air is thinner, and the heat further intensifies the effects of reduced oxygen availability. In addition, there is significant air pollution—fine particulate matter can irritate the respiratory system and make it more difficult for oxygen to reach the body. This can affect an athlete’s performance, especially during high-intensity moments,” explains the researcher.
Extreme heat presents even more challenges for footballers. During intense physical activity, the body generates enormous amounts of heat, and if that heat cannot be dissipated efficiently, physical performance begins to decline.
According to Prof. Brazaitis, when the body overheats, the brain activates protective mechanisms and starts limiting signals sent to working muscles.
“An athlete may want to run at maximum intensity, but the body no longer allows the muscles to be fully activated. Speed, power, and overall endurance decline,” says the sports scientist.
Direct exposure to sunlight creates an additional risk. Even when there is wind or the air temperature feels more comfortable, heat can continue to accumulate inside the body. In extreme cases, overheating can lead to serious health problems.
To reduce the effects of heat, tournament organizers and teams employ a variety of strategies. Mandatory cooling breaks during matches allow players to rest, replenish fluids, and temporarily reduce thermal strain on the body.
During an intense match, a footballer may lose several liters of fluid, making hydration one of the most important priorities. However, according to the scientist, dehydration is not always the primary concern – the key objective is preventing the body from reaching a critical level of overheating.
Modern sport also relies on technology to address these challenges. During training and preparation, teams use cooling vests, specialized cooling towels, and stadium cooling systems. After exertion, ice baths and cryotherapy chambers are commonly employed.
“These measures are not miracle solutions – they do not eliminate the problem of heat. However, they can delay the onset of fatigue and help athletes maintain a high level of performance for longer,” says Prof. Brazaitis.
According to the LSU researcher, without additional cooling strategies, athletes reach their fatigue threshold much sooner in high-intensity conditions. Properly selected interventions can significantly extend the time before performance begins to deteriorate.
Although players use various cooling methods during breaks, such as wet towels and cold water, it is impossible to completely cool an overheated body within a few minutes.
“The human body is a complex and integrated system. Not only the skin heats up, but also the internal organs, making heat removal the greatest challenge,” emphasizes the professor.
After matches, one of the most effective recovery methods is immersion in ice baths. Cold water not only lowers body temperature but also activates physiological processes that support faster recovery. However, such methods must be applied at the right time. For example, excessive cooling during halftime may reduce muscle elasticity and impair speed-related performance.
Teams whose players are accustomed to training and competing in hot climates may enjoy a significant advantage at the World Cup. Natural adaptation developed through living and exercising in such environments is often more effective than short-term preparation before a tournament.
Nevertheless, science offers ways to prepare the body. Within just a few days, the body begins reducing heat-related stress, but full adaptation typically requires around two weeks of specialized training in hot conditions. Once adapted, athletes sweat more efficiently, their heart rates are lower under the same conditions, and their bodies maintain optimal temperatures for longer periods. In simple terms, they can sustain high performance for a longer time.
At the highest level of modern sport, every national team is supported by large groups of specialists, including sports physiologists, physicians, physiotherapists, and performance analysts. They not only monitor players’ physical condition but also plan the entire preparation process – from heat-acclimation training and sleep management to cooling strategies and post-match recovery protocols.
Over the course of a World Cup, which lasts nearly a month, footballers must cope not only with opponents but also with travel, varying climates, altitude, psychological pressure, and accumulated fatigue. As a result, victory at the highest level is increasingly determined not only by technique and tactics; science also plays a crucial role.
At this year’s FIFA World Cup, the ability to adapt to extreme environmental conditions may become one of the invisible factors separating the champions from those whose tournament journeys end much earlier.
