Add weight to the other end of the barbell. It might be a good idea to first try this exercise without any added weight. Beginners may be fine with just the weight of the bar.
Pick the barbell up, hold it with both hands, and extend your arms outwards and a bit over you.
Feet are about shoulder-width apart, toes forward.
Keeping your abs tight, rotate to one side, lowering the barbell down by your hips. Keep your toes pointing forward.
As you rotate, your arms should stay relatively straight. The arm that is closer to your body as your rotate will bend a little bit. The opposite arm should stay straight.
Rotate until your hands are at about hip level, then use your abs to lift the bar back to the starting position.
Focus on using your abs. They should stay tight throughout the entire exercise.
You can do all reps on one side, then do the other side. Or you can alternate sides each rep.
You can count reps however you’d like. You can count each individual rotation as 1 rep, or you can count a rotation to both side as 1 rep. What’s most important is that you challenge yourself while maintaining safe and effective form.