The Flex Belt works all abdominal muscles together for you. No situps, planks or any other ab exercises. Electronic signals are sent to the abdominal and oblique muscles.through medicalgrade gel pads.Working the muscles together at once! In each 30 minute session, the muscles contract and relax 150 times. In clinical trials, 100 of users felt their abs were more toned in 6 weeks. The Flex Belt is cleared by the FDA and. The newest model packs a punch 1Increase of 50 more toning power 2Intensity power from 1 to 150 Giving a turbocharged ab workout in 30 minutes!.