There aren’t necessarily distinct “upper” or “lower” abdominal muscles. Yes you can sort of flex them differently from a relaxed state, but there’s no way to necessarily target a specific area. Obliques are different because of their function blah blah blah. If you are saying this becasue of fat in your lower abdomen, please know that that is normal and annoying and that you often have to be very lean to have that show. It’s one of the first places your body deposits fat, last to lose it.

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Decline sit ups (sometimes weighted) and cable crunches. You see your upper abs before your lower abs. That’s a bodyfat thing

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