Sitting Abdominal Stretch
(or lay over ball) – This stretch is for the abdominal muscles that run down the center of your body. It can be done standing, but many people find the sitting position easier to do, because you don’t have to worry as much about balance.
The basic idea of the stretch is simply to arch your back and lean backwards to round your abs and stretch them. The only potential issue with this stretch is that increasing the curve in your low back improves the stretch, so if you have low back problems, make an effort to keep your low back in a neutral position.
One way to approach this step is to begin by lifting your hands above your head and then trying to reach your hands back behind you. This causes your upper back to curve, which helps to stretch your upper abs.
Another approach is to keep your hands down and focus on pushing out and raising/lifting your chest. You can hold on to whatever you are sitting on to give you more leverage to help you arch your back and increase the stretch in your abs.
If you have really tight abs, it probably won’t take much back curve at all to produce an abdominal stretch. Some people can even feel a small stretch when lifting their arms above their head.