Karen Voight, the L.A. Times exercise guru, recommends this easy way to strengthen muscles that run alongside the spine.
Lie face down on a flat padded surface or mat. Straighten your legs
behind you with your toes facing the floor, your inner ankles facing
each other. Place the palms of your hands on a round, full-length foam
roller. Raise your elbows off the floor, pointing them to the sides.
Squeezing
your shoulder blades together, lightly press down on the roller as you
roll it away and arch your upper back. Pause with your chest and
shoulders off the floor. While your hips and legs remain on the floor,
roll the roller back toward you and lie down. Rest and repeat 8 to 12
times.