On October 10, 2021, the humidity was hovering at a muggy 80 per cent and the temp neared 27°C. It was the warmest start to the Chicago Marathon since 2007 – a year so brutal that hundreds of runners suffered heat issues, including heatstroke, causing race officials to shut down the event.
Thankfully, the ‘21 race went off as planned, but for many of the 35,000-odd runners – including me – the struggles were still real. I saw people hunched over aid stations and kneeling at medical tents, dealing with cramps, dehydration and other heatrelated maladies.
Some scientists predict that, by the end of this century, the global temp could reach 5°C higher than pre-industrial times. And rising figures could mean even more serious risks for outdoor exercisers. Excessive heat makes people vulnerable to heatstroke, which is one reason the World Health Organization cites heatwaves as among the most dangerous natural hazards. Heat affects almost all systems in your body,