The Shake Weight's infomercial showcases plenty of chiseled muscles.
One infomercial boasts, "Shake Weight's secret? The power of dynamic inertia!"
And the Belly Burner's infomercial presents impressive-looking scientific images.
It claims it's, "Supercharging the calorie burning process!"
Consumer Reports tested both these infomercial products.
To see if the Belly Burner really can "burn more calories faster" - testers used a metabolic analyzer to calculate the amount of calories burned while people jogged.
They ran the same test with and without the Belly Burner and compared the results.
Alex Willen with Consumer Reports says, "We really didn't find big differences in calories burned."
To measure that, testers used electrodes - comparing Shake Weight exercises to more traditional exercises.
Alex explains, "Our exercises included a modified push-up, which works the chest and triceps, and we used elastic exercise bands for the curl, which targets the biceps, and straight-arm side raises, which target the shoulders."
Tests showed there was no more muscle activity with the Shake Weight than with traditional exercises. And, in most cases the traditional exercises actually generated more muscle activity.
Testers also measured the amount of calories burned doing the Shake Weight routines, although the manufacturer doesn't promote it as a weight loss device. Turns out the panelists burned more calories walking.
Consumer Reports says while Shake Weight does activate muscles and gives you a workout, you can do better with other exercises.