Why is a racing push is not like a regular wheelchair push?

When wheelchair racing, what is the best way to use friction to get the most power and speed? This video describes major differences that move elite athletes from pushing like your grandmother to pushing like a beast!
Music: "I'm Not the King" by Audio Adrenaline © 1996 Up In The Mix Music (a division of ForeFront Communications Group, Inc.) (BMI)

Видео Why is a racing push is not like a regular wheelchair push? канала Wheels Of Fire