Abs contract when BREATHING! Just because this thing causes twitching of the muscle, doesn't make it a miracle muscle builder. If that were the case then this would work equally well for biceps, tris, pecs or any other muscle. Bottom line - it doesn't.
EMS has been used to enhance performance in world class athletes. But we're talking tnes of thousands of dollars worth of equipment including monitoring equipment. These athletes are trying to increase the ratio of fast twitch to slow twitch muscle fibers by recruiting fibers that don't respond to normal training. This is for performance, not asthetics.
As for electrical stimulus for rehab, it is used to correct nerve stimulated muscle problems/trauma due to injury, not increase muscle mass or performance on a healthy muscle.
The best way for this to work the abs is to sit on your butt, extend your legs, put it about 3 inches from your feet, and reach out to grab it and throw it in the trash. Repeat about 100 times.
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