Lower Back Stretch (and Piriformis/Glut Muscles)

• Lying with your head and spine flat on the floor (or any firm surface) cross the ankle of one leg over the knee of the other. 
• Place your clasped hands behind the knee (or you may place a towel behind the knee for easier reach) and pull the knee toward the chest. 
• Hold the stretch for a count of 10-15 seconds.  Repeat on both sides 3-5 X's or until stretch is achieved.

As with any exercise, if you have any health concerns always consult your doctor first. Some exercises  may not be suitable for your condition and may cause more harm than good.