What it does
The yoga therapy balls grip the skin as they roll, digging and loosening up the thoracolumbar fascia, the connective tissue that covers the muscles of the back of the trunk.
What to do
Lie on the floor and prop yourself up on your elbows. Then lift your bottom to make room to place two therapy balls on the grooves on either side of your lower spine, preferably on your skin so the balls have more grip. With your weight resting into the balls, use your arms and push into your heels to roll them up no farther than the bottom of your ribcage and back down.
If this propped position is painful on your neck and shoulders, you can rest your head and upper body on the floor and move the balls from side to side on your lower back, rather than vertically. Stack the two balls on top of each other and place to one side of your spine. Move your hips from side to side like you're wagging a tail to get the balls to roll across your back.
If the pressure is too great resting on the ball, either of these variations can be done against a wall.
Do this up-and-down move for 90 seconds, or about eight to 12 repetitions.