The six-pack
Rectus abdominis · musculus rectus abdominis
The long, segmented muscle down the front of your belly that curls your trunk forward.
What it does
The rectus abdominis runs from the pubic bone to the lower ribs and breastbone, on either side of the midline. It curls the trunk forward, as in a sit-up, and tightens when you cough, strain or brace for a push.
Surprising fact
Everyone has a "six-pack": bands of tendon cross the muscle, usually three or four, and they show through only when there is little fat on top.
Why it matters
During pregnancy the two halves of this muscle often move apart. The gap usually narrows after birth, and gentle core exercise helps it recover.
Nearby
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Sources
Drafted with AI help; awaiting a human fact-check against these sources.
Open in the 3D atlas · Suggest a correction · Not medical advice.
3D models: Z-Anatomy & BodyParts3D (CC BY-SA 4.0 / 2.1 JP). Card text CC BY 4.0.