The awarding of the hosting of the Football World Cup to Russia and Qatar initiated discussions about temperature and travel distances related to the game. This study examines the effect of weather conditions, travel distances, and rest days—three factors potentially causing fatigue—on running performance using player-level and teamlevel data from the 2014 World Cup. The results show that the heat index (combining temperature and humidity) significantly decreased running performance (number of sprints, high-intensity running), while a clear sky was positively associated with distance covered at high intensity. Travel distance and rest were insignificant. When these models are used to predict running performance at the 2022 Qatar World Cup, the projections show that the combination of heat and wind could hinder the performance of both players and teams and create potentially dangerous conditions. The present study has implications for policy makers regarding the choice of future host countries.