World Cup conditions hit record heat as adidas introduces a three-layer training system

Climate change is reshaping every aspect of human activity. The 2026 World Cup is the hottest on record. That much was expected. adidas answered with CLIMACOOL SYSTEM, a solution that reaches well beyond technical apparel. Built for training sessions, half-time and recovery, the system combines three elements: a cooling vest, an insulating jacket and cooling boot covers. It was originally developed for Formula 1 drivers before being re-engineered for football’s new climatic reality. Created with input from players at Manchester United, Juventus and Arsenal, CLIMACOOL SYSTEM represents a major technological advance for adidas and the clubs that work with the brand. The vest is worn over the player’s shirt and contains a specialist gel frozen before use. Once on the body, it thaws gradually, drawing heat away from the upper torso and helping lower core temperature. Over the top comes an insulating jacket with a sealed construction that traps cold air, extending the effect for almost twice as long.

Together, the vest and jacket can reduce core body temperature by up to 0.5°C and skin temperature by as much as 13°C, keeping players cool as they get ready to step onto the pitch. The final piece is the cooling boot cover, a quick solution designed to reduce heat and swelling in the feet. Worn directly over the player’s boots, it can lower foot temperature by up to 2°C. CLIMACOOL SYSTEM is built around a simple idea: giving players greater comfort when preparation and recovery matter most. Extreme heat has become another opponent. Sometimes the only answer is an entirely new way of dealing with it. CLIMACOOL SYSTEM is one of them.