Same runner, pre and post running instruction. INCORRECT, INEFFICIENT, INJURY PRONE ON LEFT: Reaching, braking, scissor kicking, heel strike on left. CORRECT, EFFICIENT, PERFORMANCE ON RIGHT: Butt kick running with forefoot strike on right.
Same runner, same day, with no instruction given in between videos. On the left, correct nice SHOE LESS forefoot strike. On the right, incorrect, with SHOES, heel strike, braking, straining. Sneakers are designed to affect the way our foot strikes the ground, yet in this video you see it affects what we do in the air. Try this experiment yourself. Video that was inspiration for Harvard Study.
![Is it the shoes? It\](http://i.ytimg.com/vi/9itkEkcQ8WM/2.jpg "Is it the shoes? It\")
