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Looks like those things that are advertised on marketing channels to get abs while sitting on a couch: https://www.amazon.com/s/ref=nb_sb_noss/143-0074589-0085364?url=search-alias%3Daps&field-keywords=Electronic+Muscle+Simulators https://www.amazon.com/s/ref=nb_sb_noss/143-0074589-0085364?... How are they helpful?