Why does energy return matter? www.marianorberg.se Iain Hunter, Ph.D., a professor of exercise science at Brigham Young University, found a clue that he wrote about in a June 2019 study in the Journal of Sports Sciences, where he attempted to replicate Hoogkamer and Kram’s 2018 metabolic cost comparison www.ragamuffins.fr study. Both studies found runners had a longer stride in the Vaporfly than other shoes, Nike Air Max 270 Dámské which makes sense from an increased efficiency perspective: The farther you travel per stride, the faster you’ll go at a given cadence.But Hunter also measured a few parameters Nike Air Max Command Mujer that the CU study didn’t, like vertical oscillation—essentially how high Nike Air Odyssey Damen Herren the runner is bouncing with each stride. There, Hunter found that the Vaporfly led runners to bounce higher, which normally would correlate with lower running economy, “unless it’s not the body that’s generating the energy to make that happen,” Hunter www.morganelafer.de says.

The CU study found slightly higher peak forces on impact for the Vaporfly (the opposite of the BYU study), but because the shoe is so soft, Hoogkamer theorizes that it actually feels less harsh to the runner, which enables the runner to take longer Nike Air Force 1 Dámské strides. That may matter over the course of a season as much as during a single race. Nike Air Max 1 Womens At the July 2019 Footwear Biomechanics Conference, Nike research scientist Brett Kirby presented data showing that runners wearing the Vaporfly sustained less muscle damage than a control Nike Roshe Run Femme group wearing other shoes. Reduced muscle soreness suggests Nike Air Max 95 Womens they could sustain higher training loads.

Whatever the mechanism, it’s undeniably effective. In addition to the CU and BYU studies, Kyle Barnes, Ph.D., a professor of exercise science at Grand Valley State, found similar running economy changes in a comparison Nike Air Vapormax Dámské with the Adizero Adios Boost 3. And in a messier but far larger sample size, the New York Times’s Upshot examined roughly half a million marathon times from public data like Strava and concluded that, on average, runners wearing the Vaporfly ran three to four Nike Air Vapormax Damen percent faster than similar runners in most other shoes, and one percent Adidas Superstar Dámské faster than the next fastest shoe, Nike’s Zoom Streak. (The authors noted that “the analysis suggests that, in a race between two marathoners of the same ability, a runner wearing Vaporflys would Nike Air Vapormax Dam have a real advantage.”)