In keeping with a 2010 study furnished by journal publishing firm Nature, runners who usually wore shoes typically struck the ground with the heels of their feet first. Why is that a problem you say? Heel-placing because it’s referred to as can generate a force up to three times your body’s weight and can lead to stress fractures and Achilles tendinitis. Contrastingly, barefoot runners have been discovered to be more likely to land on the balls of their feet which is by far much less impactful of the 2.
P90X was originally titled Power 90X before having its name shortened …