Isometric Single Leg Knee Extension – Swissball, At Wall
HOW: Place the swissball against a wall. While in a seated, upright position, kick into the ball and hold for a prescribed amount of time. As you kick, you shouldn’t be moving at all but you will feel your muscles activating.
FEEL: You should feel your quadriceps muscles in your thigh working.
COMPENSATION: Your leg shouldn’t move much as you push into the ball. Don’t arch your back.