Steve Feinberg, founder of Speedball, demonstrates three Speedball exercises at Equinox on Prince Street on Thursday afternoon, March 6, 2008. side touch shifts, step 3: conract transverse abdominus by pulling navel into spine to activate core stability. Shift all body weight laterally from right to left leg. Simulatenously rotate torso so that the left elbow points to the celing and the resistance ball passes the left shoulder.