Two-Leg Bridge
-Lie on your back and position
  your low back in neutral.

-Picture a real expensive GOLD
  coin between the cheeks of your
  buttocks and SQUEEZE it. This
  will tend to minimize the involve-
  ment of the hamstrings.

-In a toes up position, lift your
hips off the ground while you
squeeze the imaginary coin
during the entire set.

-Squeezing the butt cheeks
should NOT involve performing      any tilting of the spine.

Note: Many people have weak buttocks muscles and as a compensation, use their hamstrings. This simple 'expensive coin' visualization exercise can help activate the buttocks muscles.

This concept should be applied to any supine bridging exercise.
Competency Criteria

-Client is able to lift hips up symmetrically (and keep them up) without any back pain.

-Client does NOT perform any tilting in the spine when doing this exercise, but maintains a neutral spine.

-Client does not get a cramp in hamstrings, if they do, they are not squeezing hard enough from their buttocks. Remember the 'expensive coin' visual. Sometimes lifting the toes can decrease cramping of the hamstrings.