Back Stretches
Okay this may be hard for me to type out.
Step 1: Sit on the floor with your legs straight out in front of you.
Step 2: Cross one leg over your thigh, get it close to your body. Have your foot flat on the floor.
Step 3: With your opposite arm (say if you cross your right leg over your left, you want to use you left arm) and reach to your opposite side. Hold it for about 15 seconds and do the opposite for the other side.
I apologize if you don't understand, it's hard to word it. A good abdominal and lower back stretch is lying flat on your stomach. Putt your hands as close to the front of your body (about shoulder width apart) and push up. I notice that my back feels better after I do this.