I know what you're thinking -- it's a hand weight. Big deal. But is that really all it is? The XCO Trainer promises to "boost your cardiovascular system and increase weight loss by up to a third more" by building and toning muscles while strengthening surrounding tissue and stabilizing joints.

That sounds pretty complex to me -- let's look a little closer at what it does.

Each movement you make creates a delayed soft-impact due to the free-flowing silicone granulates within each foot-long tube. Based on the notion of "Reactive Impact," your body has to work harder to accommodate this shifting of weight, or secondary load, which generates faster results for you.

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