Do not, do not, do not exercise in this waist cincher. I have heard/seen waist cinchers that you can work out in but I can't speak on them because I have not used one. The waist cincher can be rather restrictive and it could prevent you from breathing properly during a work out which could put you on the floor (faint and fall out). It does not matter it you fall out all cute like the thing is not to fall out at all. Also working out in the waist cincher can cause it to stretch out of shape and it will no longer be snug around your body which can defeat the purse of what it is meant to do.
I know I may sound like a broken record but I have to say it; nothing replaces eating healthy and regular exercise. Work that 80/20!