When Innovation Goes Wrong: The 5 Creepiest Exercise Gadgets

Use your imagination. Or don't, actually--you might be mentally scarred.

The
fitness industry seems to roll out the next big thing about as often
and with as much fervor as gadget-mongers do. But like The Newton, some
exercise innovations just fail or fade away. For every FitBit, there's a Twisterciser; for every Bosu
Ball, there's a NordicTrack moldering in someone's basement.

There's three basic design challenges for any would-be fitness gadget: 1. Does it work? 2. Does it look...