It’s possible to run fast without clenching every muscle in your body. Just look at some of the pros like Cole Hocker, Nikki Hiltz, or Sarah Vaughn who seem to clock seriously fast times while making ...

Watch any trail race or ultramarathon and odds are you’ll find runners huffing and puffing up insanely steep climbs or tip-toeing atop razor-thin mountain ridges with poles in their hands. But despite ...