Electric Muscle Stimulation (EMS), also known as neuromuscular electricalstimulation (NMES) is the elicitation of muscle contraction using electric impulses. The impulses mimic the action potential coming from the central nervous system, causing the muscles to contract. EMS is proven to be quite effective as a proactive tool for muscle strengthening. The Hip Trainer is highly efficient EMS training for targeted training of your hip and butt muscles. Train your hips highly effectively in a minimum of time: 2-3 training sessions per week to get fitter and stronger. The Hip Trainer is for women who want to increase their fitness in the long term and build muscle mass efficiently.