Nike says the shoes are about 4 percent better than some of its best racing shoes, as measured by how much energy runners spend when running in them. That is an astonishing claim, an efficiency improvement worth almost six minutes to a three-hour marathoner, or about eight minutes to a four-hour marathoner.
And it may be an accurate one, according to a new analysis by The New York Times of race data from about 500,000 marathon and half marathon running times since 2014.
If you like well designed charts and data, you’ll like this report. The Times used public (user entered) data from social running app Strava to corroborate Nike’s claim, and the results seemingly back up Nike’s statements; runners who wore Vaporflys were consistently faster than runners who didn’t.