Miami-bound World Cup players face a formidable opponent beyond their rivals: the city’s oppressive heat and humidity, which threaten to transform the tournament into a grueling test of endurance as much as skill.
Teams accustomed to cooler climates are particularly vulnerable if they haven’t had sufficient time to acclimatize, warns Dr. Jason Kostrna, an assistant professor and graduate kinesiology program leader at Florida International University. Kinesiology is the study of movement, exercise, and physical performance.
The challenge lies in the air itself.
“Unfortunately here in Miami, it’s very humid and so when you go and exercise, you start dripping sweat,” Kostrna told Reuters. “That means that you are not evaporating it. It’s just rolling off you and you are not getting that heat loss.”
This physiological battle is intense; as players’ bodies struggle to cool, their hearts work overtime, pumping blood to the skin in a desperate attempt to release heat through evaporation – a process rendered ineffective by Miami’s sticky atmosphere.
“Then when it can’t, it starts to really try and increase that heart rate,” Kostrna explained.
This heat stress compounds the immense pressure of representing one’s country, creating an additional burden that impacts both physical performance and mental sharpness. Dr. Kostrna predicts a noticeable shift in gameplay.
“You’ll start to see the pace of play maybe drop a little, you’ll start seeing that decision-making becomes a little more conservative. Whether that’s consciously or unconsciously, depends on the athlete,” he added.
Temperatures across World Cup host cities are already exceeding historical averages. When considering the Wet Bulb Globe Temperature (WBGT) – a measure that incorporates humidity, sunlight, and wind speed alongside air temperature – the outlook is stark.
“Our wet bulb globe temperature for some of these games could be close to 120 degrees Fahrenheit (48.8°C) when you factor in radiative heat, humidity, the ambient temperature and throw in a little bit of the plastic or concrete jungle effect,” he said.
“If we do not actively work to take care of everybody, that is enough to cause major heat illness.”
While Miami-Dade County is implementing heat mitigation measures for fans at Miami Stadium, including cooling stations, water trailers, hydration zones, and misting areas, the solutions for players are less robust.
Three-minute hydration breaks have been introduced for all games, but Dr. Kostrna views them as a “band-aid solution” if athletes haven’t adequately hydrated in the days leading up to a match.
“If you’re behind on hydration, this is not magically going to fix it,” he stated.
He acknowledged their limited benefit: “For the athletes, it can help bring their heart rate down, get some hydration. (The hydration breaks) can be a little bit longer, that would probably be better.”
His primary advice for competing teams is clear: arrive early and acclimatize.
“My hope is that there are not any teams that are truly just showing up off the plane and they’re experiencing this for the first time,” Kostrna said.
“Hopefully they have been in town for weeks and have been practicing in this (heat). That should be enough even if you are somebody who is coming from one of these colder regions, your body will adapt over those weeks.”
