This exercise adds a variation to a standard crunch for abdominal muscles.

How to perform this exercise:

• Start on with you back on a stability ball
  
• Place your hands behind your head
  
  • You can also fold your hands across your chest instead
• Try to maintain a back ward pelvic tilt while raising your shoulder blades off the stability ball
  
• Return to starting position on the stability ball and repeat
  
• Repeat this exercise 10 -15 times