While doing the spin crunch is it OK to use your elbows for help?
The spin crunch is one of the best abdominal exercises. What makes it an awesome abs exercise is that you are forced to use every function of your abs to be able to spin. It's difficult at first, but don't use anything but the power in your abs to spin around. It will get easier as your abs get stronger. At that point you can add reps or even hold a weight while you complete the spin crunch.
Spin crunches or demonstrated in the Fat X Fat Burning Workout 3