Cross-over Crunch

• This exercise is often referred to as the "bicycle." Lie on your back and bring your legs into the air, bending your knees at a 90 degree angle. Place you hands behind your head with your elbows bent and your finger tips gently cradling the back of the head. Raise the upper body as you rotate your right shoulder to your left knee. At the same time, pull the left knee in closer and extend the right leg out, parallel to the ground. Switch as you twist your left shoulder to your right and bring your right knee into meet it while extending the left leg out.
  
  Perform the movement in a slow controlled motion, switching from side to side. Your legs should cycle in and out as your upper body rotates to meet your knee as you bring it in. Keep your elbow out wide and don't yank your head and neck. Focus on bringing your opposite shoulder to opposite knee. Exhale as you twist to each side and inhale as you are switching. Complete one to three sets of 15 to 20 repetitions on each side.
  
  

Vertical Leg Crunch

• Lie on your back with your legs elevated and knees bent at a 90 degree angle. Place your hands behind your head just as you did for the cross-over crunch. Now, extend your legs into the air a little straighter. Aim to get them as straight as possible with only a slight bend in the knee and cross them at the ankles. Keep the legs where they are and crunch up by raising your upper body off the floor and up toward your legs. Keep the chin lifted off the chest and the elbows wide as you contract the abdominals and crunch up. Exhale as you crunch up and inhale as you release. Complete one to three sets of 15 to 20 repetitions.
  
  

Reverse Crunch

• Lie on your back on the floor and elevate your legs with the knees at a 90 degree angle. Place your hands along your sides on the floor. If you have problems with lower back pain, place your hands under your buttocks for support. Contract your lower abdominals as you curl you knees in towards the chest. Slightly lift the buttocks, thrusting your legs into the air. Hold the contraction for about three seconds and release. Exhale as you curl in and contract, inhale as you return to the starting position. Complete one to three sets of 15 to 20 repetitions.