On your marks...
Breaking the 2-hour marathon barrier — that is, running a marathon in less than 2 hours — has long been seen as the holy grail of running, a feat that some people think could even be impossible. But, on May 6, 2017, three athletes will attempt to break the 2-hour barrier as part of Nike's Breaking2 project. The experiment will take place on the 63rd anniversary of another huge running milestone: when Roger Bannister became the first person to break the 4-minute mile, completing it in 3 minutes and 59.4 seconds. [Read more about Nike's "moonshot"marathon attempt]
But what does it take to run the fastest marathon time in the world?
There are three main contenders trying to break the 2-hour marathon barrier: Nike, Sub2 Hours project and Adidas.
Nike's Breaking2 project is working with three runners: reigning Olympic marathon champion Eliud Kipchoge, current half-marathon world-record holder Zersenay Tadese, and Lelisa Desisa, winner of the Boston Marathon in 2013 and 2015.
The Sub2 Hours project is a much broader research initiative to understand to understand the science of running the fastest marathon in history. This includes improving scientists' grasp of nutrition, biomechanics, bioenergetics, physiotherapy, the role of genetics and how to build effective anti-doping practices.
Adidas has developed a new shoe, dubbed the Adidas Adizero Sub2, as part of its attempt to help runners break the 2-hour marathon barrier.
It has taken 100 years for elite male runners to bring marathon finish times down to where we are today. The current marathon world record is held by Kenyan runner Dennis Kimetto, who ran the Berlin Marathon in 2014 in a time of 2:02:57.
When and where
Nike's Breaking2 attempt will take place at the Autodromo Nazionale Monza, a Formula One racetrack located north of Milan, Italy. The ideal conditions are about 54 degrees Fahrenheit (12 degrees Celsius) and overcast weather.
It's in the genes?
When it comes to the influence of genetics on marathon performance, "we know very little," Yannis Pitsiladis, founder of the Sub2 Hours project and a professor of sport and exercise science at the University of Brighton, in the United Kingdom. However, there are some common denominators, he said.
"What we do know that is going to be required is a very high engine, and what we mean is a very high aerobic capacity," Pitsiladis said. This means the runner is able to take in a lot of oxygen and transport it to the muscles.
Second, the runner has to have good running economy, which means the athlete can use energy and fuel very efficiently.
Finally, scientists are taking into account the runner's environment and personal history, such how long they've been running or whether they live at high altitudes.
Nike Zoom Vaporfly
As part of its Breaking2 project, Nike designed a new shoe called the Nike Zoom Vaporfly Elite. The shoe features lightweight knitted material in the upper part of the shoe; a full-length carbon fiber plate to minimize energy loss; a foam sole made of a lightweight material, dubbed ZoomX, that Nike says is lighter than standard foam; and an upturned heel to reduce drag.
Adidas Adizero Sub2
Adidas has kept the overall weight of its shoe a secret, but the Adizero Sub2 shoe features ultralight mesh material on the upper part of the shoe; cushioning from what Adidas calls its lightest foam in the sole; and an outsole that is designed to deliver maximum grip to save energy.
Before races, most endurance athletes load up on carbohydrates, which are a main source of fuel for the body. During a race, athletes consume sports drinks and gels that contain a blend of carbohydrates such as glucose and fructose, with added electrolytes.
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Denise Chow was the assistant managing editor at Live Science before moving to NBC News as a science reporter, where she focuses on general science and climate change. Before joining the Live Science team in 2013, she spent two years as a staff writer for Space.com, writing about rocket launches and covering NASA's final three space shuttle missions. A Canadian transplant, Denise has a bachelor's degree from the University of Toronto, and a master's degree in journalism from New York University.