12 Moves to Build a Stronger, More Functional Core

This simple-but-challenging core exercise works "your entire rectus abdominis, core muscles from your pubic bone and ending at the sternum," says Villarson. To modify this move, bend your knees.

How to Strengthen Your Core With V-Ups:

1. Lie faceup on the floor with arms and legs extended and resting on the floor. Lift up both arms and legs so they're hovering off the floor in a hollow-body hold.
2. Simultaneously reach your arms and legs toward each other, as if you could touch your toes directly over your belly button.
3. Lower your arms and legs, without allowing them to rest on the floor. That's one rep.