Instructions

1. 1

   Lean at around 45 degrees against a wall. Your feet should be together, glutes contracted.

2. 2

   Begin by lifting your right knee quickly, pausing, and then driving it straight down into the ground.

3. 3

   Switch legs, raising the opposite knee, and then attacking the ground straight down.

4. 4

   Repeat once more with your right leg, and as soon as the right foot strikes the ground hammer them out rapidly, alternating left and right as fast as you can.