Recalibrator is a workout built around Jumping Jacks that form the axis of its routine. This means your form needs to be pitch-perfect. Arms must come up over the side, meet at the very top of your head, in sync with your feet being out and then forcefully brought down, working all arm muscles in both movements. Be on the ball of your feet as you bounce and try and remain on the same count of Jumping Jacks throughout. There are also basic burpees with a jump, but then again you expected that.