WHAT DETERMINES HOW MANY ABS I CAN GET?

Assuming you're a human being, you have exactly the same number of abs as everybody else: two.

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They're called the rectus abdominis, a pair of flat, parallel muscles that are commonly spotted on underwear models, pro athletes and anyone else with very little belly fat.

Now, there are other abdominal muscles - shoutout to the transversus abdominis, plus the external and internal obliques. But let's assume your question is about the hallowed 'six-pack', those midsection muscles that look like an anatomical ice tray. Those aren't six muscles at all, just the regular rectus abdominis that we're all born with.