I just borrowed a swiss ball from my cousin and I was wondering what's the proper procedure to do ab excercises on them for the best results? Am I supposed to put my buttocks on the edge of the ball and rest my back on the rest of the ball with my feet at a 90 degree angle? Then do crunches with my hands behind my head (no interlocking) and do a couple of sets? The first time you use the swiss ball are you supposed to have some stability or balancing problems? Because I fell off of it backwards and hit my head on the floor.
