The crunch workout is all about floor crunches. Strong abdominals help you look lean, sexy, and fit. This abdominal routine includes just crunches, no Swiss balls, wobble boards, tubing, cables, or machines. We suggest you perform this workout routine at the end of your training session or on an off day. If you've performed a heavy workout that included overhead squats, deadlifts, or olympic lifts, you can skip the crunches.