This exercise is not a secret but most of us do not include it into tummy workouts. It is most probably the easiest way to shrink your waistline and have flat abs if you perform this workout correctly and regularly. The main target of this exercise are transversus abdominis muscles. You can do it any time standing, walking, on your bed or kneeling without needing a single exercising equipment. The exercise I am talking about is called stomach vacuum.
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