Springboard Diver Abs with Jon Morris

Do 3 sets of 20 crunches each in the following 4 positions (do not take a break between positions). 1. laying flat, arms behind head with fingers locked on neck. 20 crunches… (lift no more than six inches off the ground). 2. pull knees to chest, arms still behind head, 20 more crunches. 3. extend [...]