Electrical muscle stimulation is a non-invasive procedure that uses light electrical pulses that are transmitted to specific areas of the body, usually through electrodes placed on the skin. There are many different types of electrical stimulation. Some are more beneficial for pain relief or to reduce inflammation, some for muscle spasm, and some actually cause muscles to contract and can be used to reduce muscle atrophy. Some have combination effects. Some examples of muscle stimulation include interferential current, low-volt and high-volt direct current.