Extreme heat has changed the way this year’s World Cup is played. The high temps can impair players’ focus and decision-making.

A neuroscientist explains how extreme heat can impair players’ focus and decision-making, and when hydration breaks actually matter.

Extreme heat has changed the way this year’s World Cup is played. The high temps can impair players’ focus and decision-making.

Guardian analysis finds 19% of games reached heat levels warranting delays, as Fifa defends its player safeguards