Keto Ultra Diet which you have worked out the deep core muscles, now its fine to go on and work those outermost, rectus abdominis body. Now go ahead and do some crunches. Weight Loss Tips If you'd like the greatest crunch exercises do these a swiss ball. This will give you extension as well as flexion. A lot sit up all Keto Ultra Diet way in order to incur maximum benefits. Do a crunch flex and flex stretch about 20 cycles.