How is climate change affecting marathons?

Researchers have found there’s a “sweet spot” for marathon temperatures where runners perform their best. But as the planet warms, those ideal race-day conditions will become less likely if fossil fuel pollution remains unchecked.

What are optimal marathon running temperatures?

Scientists have studied how temperature impacts the speed of marathon runners and found that for runners at the elite level, men run best in cooler conditions (on average, 4°C or 39°F) and women do better at warmer temperatures (10°C, 50°F). For recreational runners, men run best at 6°C (43°F), and women run best at 7°C (44°F).

Around 1.1 million people finish a marathon each year, but as the planet warms due to climate change, the cool, comfortable race-day conditions that help runners perform their best are becoming harder to find.

For most recreational runners, the odds of racing in perfect conditions are already slim, and for elite athletes chasing records, rising temperatures have made record-breaking runs in some races nearly impossible.

A different future will require significant and lasting emissions cuts to minimize carbon pollution.

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