Just turn it on and step onto the mat to build muscle in your legs, aiding in dieting and preventing muscle atrophy. Electricity flows, but the amount can be adjusted. You can easily train by simply placing the part you want to exercise on the mat, whether you're watching TV, reading a book, or just sitting. It's rechargeable and can be used repeatedly! If you're concerned about lack of exercise, sagging, or anything else, give it a try!