i have been using the belt for 5 weeks for 30 minutes a day in conjunction with a healthy diet, but no additional exercise as i am ridiculously busy. even with this minimal effort, i have noticed an improvement in my posture due to stronger core muscles. i have also started to see a little bit of definition and my stomach is nice and flat for the first time ever! i was dubious at first; as while you can feel the muscles contracting during use, there was no pain the following day like you get with 'normal' crunches. i kept upping the intensity but i would still feel fine the next day! now, though, i can see the difference and know for sure that it is working. it only took 3 weeks before i could see a change, and i intend to persevere until i have abs to rival any celebrity!the only down side is that the batteries don't last that long, and that the belt doesn't go quite tight enough for me. might be worth adding another bit of velcro. the pads, i am assured, can be made to last longer with water--based lubricant; and without that should still last a good month or so. i would recommend this product to anyone wanting to improve the appearance of their stomach; i've hated my wobbly pot--belly for years and nothing shifted it until now. thrilled with the results :--)