Can the Muscle Walls of the Abdomen Be Tighten Without Having a Tummy Tuck? (photo)

I am curious to know if a full tummy tuck needs to be performed to tighten both the upper and lower muscles of the abdominal wall? I have 2 stretch marks from birthing two children; I don't have a pouch like most moms I know... rather my stomach just protrudes out even though I work out (5'3", 125lbs).

