2B Swiss-Ball Jackknife w/Pushup
Sets: 2-3 Reps: 10 Tempo: 311 Rest: 60 Seconds
Get into pushup position, resting your feet on a Swiss ball . Contract your abs and roll the ball toward your arms until your knees nearly touch your chest . Reverse the motion until you are back in pushup position, and perform a pushup with your feet elevated on the ball . That's one rep.