The Ab Coaster promises to give you rock hard abdominals within weeks, so Consumer Reports decided to put their claims to the test. Especially the one about its patented “bottom up” method.

The device says it works by engaging your whole abdominal system, which it does, but so does a modified crunch that you can do yourself. And you’ll save yourself $400 to boot.

For more on the Ab Coaster and other sports and exercise equipment reviews, check out Consumer Reports.

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