I love this exercise. Not only does it work your waist muscles , your TA and provide rotations for your spine - it also acts like a sort of soothing massage for your diaphram. We often call this “the Rennie Exercise” as it can help to relieve an irritated diaphram ie. indigestion, hiccups, heartburn etc. Start in level 1 (the first part of the video) if you are a beginner....