This video demonstrates the four keys to a powerful freestyle. The first is internal shoulder rotation. Rather than holding your arms out straight, rotate the shoulder inward to bring the elbow up. Point your fingers downward and catch the water with your entire forearm. Secondly, pull with your elbow bent rather than a straight arm. After you've extended your arm, bend the elbow to begin the catch. Third, use elliptical or rounded movements, that is pull through in the shape of an "S". Fourth, release the water from the hand before bringing the arm back up so the hand is empty when it comes out of the water.