Advanced exercisers may attempt abdominal exercises performed on an incline bench. When executing any abdominal exercise, keep your neck aligned with your spine at all times and draw the belly button toward the spine to maximize activation of the muscles. The American College of Sports Medicine recommends you do only 15 to 20 repetitions of any abdominal exercise. Set the incline for these exercises anywhere from 10 to 45 degrees. Greater degrees of incline require more strength, so start modestly at first.
Straight Leg Drop
This exercise resembles a Pilates exercise known as the "double straight leg stretch," but when performed at an incline it increases the activation of the core. Lay with your head at the high end of an incline bench and extend your legs straight above your hips. Hold onto the top edge or sides of the bench for stabilization. Slowly lower your legs a few inches towards the bench, keeping your back pressed to the bench. If your back begins to arch, you have gone beyond your limits. Exhale and return your legs to the starting position to complete one repetition.
Straight Leg Reverse Crunch
This move impacts the lower portion of the rectus abdominus and the transverse abdominus. Lie on the bench with your head at the high end of the incline---grip the top or sides of the bench for support. Lift your legs toward the ceiling, aligning them directly above your hips. As you pull your belly in toward your spine, lift your legs and hips up as if you were trying to stamp footprints on the ceiling. Hold for a split second and return to the starting position with control. According to "Oxygen" magazine expert Julie Childs, your butt should lift no higher than two inches off of the bench.
For this exercise, lay with your head at the lower end of the bench, knees bent and hook your feet under the cylindrical supports (if your bench has them). Cross your arms in front of your chest and draw your navel towards your spine. As you exhale, lift your head, shoulders and middle ribs off of the bench. Pause for a moment and return to start to complete one repetition.