Listen to the Summary of Robert Donald Cooley's The Genius of Flexibility in 20 minutes. Please note: This is a summary & not the original book. When you're playing tennis, you'll notice that when you're in the rhythm of your service game, your body is serving the ball naturally and correctly. Your mind is in the zone. When you begin to overthink or control your arm movement too much, your fun is dampened and you start to chock...