The 2026 Men’s FIFA Football World Cup: Evidence-Based Guidelines to Protect Player Health and Performance from Environmental Challenges

The Men's 2026 Fédération Internationale de Football Association (FIFA) Football World Cup (FWC) will take place across the USA, Mexico and Canada, with host cities spanning ~ 4300 km east-west and ~ 4000 km north-south. The geographical distribution exposes players to environmental challenges that can negatively impact their health and performance, including: (i) extreme heat; (ii) altitude; (iii) air pollution and seasonal allergens; and (iv) travel. FWCs have never presented this combination of extreme environmental factors. Extreme heat is expected in 14 out of the 16 host cities, with historical maximum wet-bulb globe temperatures ranging from 21 to 35 °C (mean ambient temperatures: 19.1-32.7 °C). Matches in Guadalajara (1566 m) and Mexico City (2240 m) will take place at altitude. Travel requirements and increased human activities during mega-events increase the susceptibility of players/athletes to, and risk and spread of, airborne illnesses. Changes in air pollution and allergens from players' domestic club locations and between host cities will also impact player health. Circadian misalignment (up to 19 time zones may be crossed to reach team base camps) and travel fatigue (up to 3 time zones crossed and a 7-h in-tournament flight time) may impact players' mental and physical health, decrementing athletic performance. Teams adopting evidence-based guidelines to mitigate the impact of these environmental challenges will be best prepared to protect player health and performance during the tournament. Therefore, this review presents the predicted environmental challenges using the best available data and models and provides evidence-based long- and short-term strategies to best mitigate their impact. Relevant clinical considerations for each challenge are also outlined.