For how we live.
For heat exhaustion, rest and shade usually suffice. For heat stroke, a meta-analysis of 63 studies found immersion in cold water cooled the body faster than anything passive — the intervention the evidence agrees on.
A 14-year hourly analysis of the heat index finds a rising trend and a 2025 that set records, with a 'feels-like' temperature reaching 52C as early as 7am on some days.
As the 2026 World Cup opens, researchers point to last year's Club World Cup as a preview: 31 of 57 matches were played at heat levels guidelines say should have stopped play.
A study across nine facilities in Makkah recorded 1,576 cases of heat exhaustion or heatstroke and a 4.9% mortality rate — in a region where heat-health research remains remarkably thin.
A rapid attribution study finds human-caused warming made this month's record Southwest heat wave far more likely, and doctors warn the early timing caught people unacclimatized.
Play was suspended on outside courts on Saturday when the tournament's five-point Heat Stress Scale maxed out. A ball kid collapsed during a match the same day. The threshold is set on physiology, not air temperature.