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Plenty of people, from athletes to those with busy lives or past injuries, would like the benefits of a two-hour workout in just 20 minutes without excess strain on their joints. That’s the promise of Katalyst’s four-piece bodysuit, the only FDA-­approved consumer device to use full-body electrical muscle stimulation, or e-stim. When you use Katalyst for a strength session, strategically placed pads gently zap your muscles with electricity, which founder and CEO Bjoern Woltermann says activates double the number of muscle fibers that standard training does. Sessions, he says, will leave you tired.

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