Should you buy the Nike Vaporfly 4% Flyknits? We asked a podiatrist.

“However, the new rules also effectively tamped down any hope that competitive brands could offer their own design for the Olympic Games.” (NBC News will be broadcasting the Summer Olympics from Tokyo.) Nike — which calls the Vaporflys "the fastest shoe we've ever made” — disagrees that they provide an unfair advantage. It is engineered for repeated impact due to the fact that it is lightweight, thin, and breathable."The shoe’s material on top, VaporWeave, almost looks sheer — it’s paper thin, breathable, absorbs less water, and lowers the weight of the shoe, which helps with speed (remember that "4%" in the Vaporfly's name)."I am also happy to see the VaporWeave engineered woven mesh, which helps with additional perspiration and less water retention, especially in long-distance runs," Petkov says. I recommend that my private clients arm themselves with the best gear in order to get in the best workout.) If you’re a walker, you’ll feel like you’re walking on a bouncy surface that’s propelling you forward, which can increase your walking speed and help get your heart rate up faster than otherwise.If you're running off-road or during a hike, these may not be the best option."My main area of concern looking at the Nike Vaporflys is stability," Petkov advises.