The Knee Jack exercise works your abs, shoulders, obliques, and legs.
-Okay, this is one of my favorites. This is a wood chop knee raise. You simply bring the weight to the knee and go right into a wood chop, so, knee, wood chop. Now, I want you to really squeeze and flex. Now, do about 15 repetitions on one side, just give a little toe tap to the side, really raise, you're in a diagonal, and then I want you to switch sides, and do 15 repetitions on the other side, for a total of 30 repetitions.