Stomach vacuum is a German technique that has been around for over 100 years. It's known as the "great stomach flattener" and it can help you look more toned and fit. This vacuum cleaner technique allows you to lose weight by sucking in your stomach and holding it until your abdominal muscles are completely fatigued, which makes them tighten up! Find out how long to hold your breath before release, what this does for your body, and how to do this exercise correctly with these easy-to-follow steps below: