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Ab belts may cause muscle contractions if used properly. But the belt alone cannot produce six-pack abs. The real challenge to ab definition is the layer of fat that lies right under the skin, hiding muscle tone.
For example: Crunches only work the front of your abs and donât create a very strong contraction, since it's just your own body weight youâre working against. The ab crunch machine that you sit in at the gym mostly just makes your hip flexor (or your sitting muscles) work hard and not your stomach.