Get Rock-Hard Abs, Sculpted Arms, and a Butt Like J Lo's With These 21 Exercises

This move will strengthen your core while sculpting your six-pack muscles.

• Position yourself on a vertical bench with your back flat against the back support and your hands firmly gripping the handles.
• Pull both knees up into your chest, and with control, lower them back down to the starting position.
• From here, fully extend both legs and lift them up until you've reached parallel (or as far as you can go). Lower your legs back down to the starting position.
• This completes one rep.