Next up is the barbell ab rollout, which will work your core. Place a barbell, loaded with 5-or-10-pound plates, on the floor in front of you so that you are on your hands and knees (as in a kneeling push-up position).
This will be your starting position. Grip the barbell with both hands shoulder width apart.
Slowly roll the bar forward, stretching your body into a straight position.
After a pause at the stretched position, pull yourself back to the starting position as you breathe out.