New study looks at effects of climate change on marathons

On November 2nd, 2025, over 50-thousand runners pounded the pavement in New York City for the world’s largest marathon. Luckily, the weather cooperated there this year, but a newly released study reveals how climate change may change expectations for runners worldwide in the years to come.

CBS Austin Chief Meteorologist Chikage Windler is an avid runner. “As a runner and a meteorologist, the one thing that’s most important is temperatures. And finding those optimal temperatures is becoming increasingly more complicated,” she says.

Chikage Windler in College Station (Chikage Windler)

Temps in the low 60s welcomed a record field for the Oktoberfest Half Marathon at Texas A & M University. The College Station Marathon is 6 weeks away, twice as long, and hopefully cooler.

Oktoberfest runners (Chikage Windler)

“26 plus miles is hard on its own, but you have to have that sweet spot of temperature. So we really want to understand how is climate change impacting these big races and our ability to run them as well,” says Shel Winkley, a meteorologist at Climate Central.

Climate Central Meteorologist Shel Winkley (Chikage Windler)

Winkley is a College Station-based meteorologist with the nonprofit, which released a study on the effects of climate change on optimal marathon running temps in late October of 2025. It compiled data on 221 marathons worldwide, including all of the Abbott World Majors like New York City, Boston, Tokyo, and Berlin.

Marathon Dashboard (Climate Central)

“Just the optimal temperature for your body to perform. And so for elite male runners, that sweet spot is about 39 degrees Fahrenheit. Now for elite female runners, that sweet spot’s higher. It’s a threshold of 50 degrees Fahrenheit,” Winkley explained.

Marathon Map (Climate Central)

The elites are the top 1%. But what about the middle of the pack?

“I would say maybe like 65 degrees. Probably would be my perfect run weather,” says Kyleigh Carter.

Kyleigh Carter (Chikage Windler)

Carter is a runner who was celebrating her Oktoberfest finish.

Hydration at the finish line (Chikage Windler)

“If it was too hot, I would probably have to take breaks or drink more water, have to stop more often. But because of the weather, I was able to run straight through,” she says.

Nat Nettum is a UPS driver. He says that helps him handle the heat.

Nat Nettum (Chikage Windler)

“You acclimate to it over years of doing it, and you know, the heat doesn’t really affect you as bad as people who have inside office jobs,” he says.

“So the optimal temperatures for just your recreational runners, about 43, 44 degrees for both male and female,” says Winkley.

He adds Tokyo is the major marathon most likely to provide optimal running temps, but the 2025 race was anything but, averaging 59 degrees, a whopping 15 degrees above normal. Winkley says this unusual warmth was made 3 times more likely due to climate change.

Chance of optimal running temperatures (Climate Central)

“Then we’re looking into the future at 2045. So the races that we know that are going to be the hardest to find those optimal temperatures, the Tokyo marathon, especially for elite male runners, the Berlin marathon which this year had record heat around,” explains Winkley.

“I think that it’s a big factor with running. I mean, if it’s super hot outside, I’m just not going to go run,” says Carter.

Marathon Comparison (Climate Central)

“We understand that burning things like coal, oil, and methane gas are putting this heat-trapping pollution into our atmosphere. Being able to get more renewables into our electric grids, that’s going to be the biggest way that we can bring down that heat-trapping pollution and save our marathons going forward,” Winkley explains.

Runners at Oktoberfest (Chikage Windler)

Taking steps in the race against climate change.

Read the full report from Climate Central here: https://www.climatecentral.org/climate-matters/marathons-2025

This story aired on CBS Austin News Saturday, November 1st, 2025, at 10 pm.