You can take toe raises
which are a great reverse crunch type abdominal exercise a step further by
adding a resistance band to the mix. All you have to do to incorporate the
resistance from the band is place the middle of the resistance band over the
middle of your feet, (there should be a grove in your sole of your shoes that
fits the resistance band nicely) hold the handles and perform the motion.
The resistance band or tube toe raises are great for progressing the toe
raise for those have already mastered the form and find it easy to perform a
set of 20+ repetitions. You can add toe raises in any exercise program which
involves the abdominals.