Leg Raises

1. Lie flat on your back on the floor, with your lower back firmly against the floor.

2. Stabilizing your body and keeping your lower back flat on the floor, lift your legs straight up until they are perpendicular to your torso, then lower back until close to the floor, but not touching. Repeat.

The Work-Out: Do 1-2 sets of 10-20 repetitions.

Make sure to: Make sure your lower back is always flat on the floor - if it risews up, this puts stress on your lower back and could cause soreness or injury.

Take it Up a Notch: To advance this exercise, use an inclined bench.