They are a scam.. The amount of electricity needed to actually gain muscle would be so high that you would burn your skin. They might work for someone who does absolutly nothing and has no muscle already, but even then it would be minimal. Best bet is to eat right and workout. You need to understand that everyone has abs, they are just covered in fat. if you do some regular cardio work, eat right, and train your abs 1 or 2 times a week eventually they will show through.. I also recommend training your lower back because a strong lower back and abs will give you a very strong core
