Running Out of Time

How marathons are racing the clock as they try to beat the heat

By Pablo Alvarez


In September of this year, Cristian Rosatti, a 45-year-old amateur athlete, was running a half marathon in Cozumel, Mexico, when the temperature, generally in the low 80s, reached 105 degrees Fahrenheit by noon. Rosatti, who has run more than 50 marathons and triathlons since 2012, still recalls how the humidity made it feel hard to get enough oxygen no matter how deep he breathed.

Along a route that looked like something out of a painting—next to the sea, with palm trees symmetrically placed along the street—Rosatti got dehydrated, and both of his legs cramped. He ended up walking across the finish line. After the race, the cramps spread to his abdomen and even his throat in his hotel room. It “was my worst performance by far, almost 40 minutes slower than my usual time,” he said.

Running is one of the most inclusive sports due to its simplicity. All you need is air to breathe, a body that can take on a course, a place to run, and good weather. But today, because of climate change, marathon enthusiasts are running out of time to protect even these basic requirements.

Runners have had to sweat it out for the New York City marathon. (Ed Yourdon)

Sport and environment are interrelated—you cannot separate one from the other.

—George Kazantzopoulos, chairman of the Association of International Marathons and Distance Races.

Heat and humidity aren’t the only problems. Wildfires regularly blaze throughout the western U.S., creating increasingly dangerous poor air quality. Runners, whether professional or amateur, are more exposed to these adverse effects because they take in more air than people who don’t work out. Higher temperatures also are a problem for runners because it leads to dehydration and can endanger their overall health.

Marathons worldwide are responding by moving races to colder times of the year and colder places. Even so, those in hotter climates are seeing lower signups as runners seek races in more temperate conditions. The 2020 Olympics, as a good example of this phenomenon, opted to move the marathon from Tokyo to Sapporo due to heat concerns.

In September 2019, marathoners competing at the IAAF World Championships run during the night for the first time ever to reduce the risk of heatstroke. That’s because the championships took place in Qatar, where the average daytime temperature in September can reach over 100 degrees Fahrenheit. Even with these measures in place, the temperature by midnight was around 90 degrees Fahrenheit. Only 60% of the athletes were able to finish the competition.

Marathons weren’t on the agenda when world leaders met at the 26th session of the United Nations’ Conference of the Parties in Glasgow to try to broker a global shift away from fossil fuels to dramatically slow global warming.

Yet the long-term impact of the conference’s agreements will affect many aspects of everyday life, including sports like running. Beloved events and the pride of many cities, from Boston to Brisbane, marathons provide a potential platform to raise awareness of the need to lower emissions and keep the planet from overheating.

“Sport and environment are interrelated; you cannot separate one from the other. It is for the interest of all of us in the sporting community, regardless of the discipline, to protect the environment very actively,” George Kazantzopoulos, chairman of the Association of International Marathons and Distance Races, told the NYCity News Service.

The globe has already heated an average of 1.2 degrees Centigrade, and research suggests that these higher temperatures are already having an impact on runners’ speed.

In a report called The State of Running 2019, a Danish statistician and former competitive runner Jens Jakob Andersen and his team found a clear connection between temperatures and marathoners’ finish times. Their analysis, the most extensive study of its kind, includes 107.9 million results from more than 70,000 events between 1986 and 2018. In 1986, the average finish time for a 26.2-mile marathon was 3 hours, 52 minutes. In 2018, it was 4 hours, 32 minutes, a slowdown of 40 minutes, and 14 seconds.

A study of this kind is not capable of showing cause and effect. Still, scientists suspect that climate change may be the reason for the slowdown in runners’ times. “I do think runners already select races depending on weather, and they prefer colder climates, between 10-16 degrees Celsius (50-60 degrees Fahrenheit),” Andersen said.

In another study published in August, Paul Ronto and Vania Andreeva Nikolova have substantiated the link between climate change and runners’ slowing times. Ronto is an avid runner with 6 marathons under his belt; Nikolova holds a Ph.D. in Mathematical Analysis. The researchers from the second study are colleges with the authors from the previously presented research.

Marathon organizers have been trying to accommodate changing the event’s date to colder temperatures. The New York City Marathon, for example, was once a mid-September event. In 1976, it was moved to the end of October and, in 1986, after some incidents in which runners experienced heat cramps ( including 1984’s winner, Orlando Pizzolato), to the first Sunday in November.

The organizers of the New York race will probably not want their event to be one where it is harder for people to set their personal best. But as with many things in life, the success of both marathons and climate change issues is subject to how well we prepare ahead of time. The clock is ticking.