So with this intu-flow, once you start to get some basic movement in each joint then you start to do circles. When I first started I was so tight I really couldn't do this but with constant work and practice I'm getting better at it. They also call this circular strength training or CST. The way Scott Sonnon explains this, the circular movement of the joint allows synovial fluids to get in there to lubricate the joint. Also, the torque helps to gently breakup adhesions and decompress the joint. On a scale of 1 to 10, 10 being very uncomfortable you want to keep your pain level at a 4 or less as you do the movement. The idea is to gently shave away the tension day after day and gradually increase the flexibility.