If in case you are not familiar with what these two are, you should know that these two are machines that are used in hospitals. TENS stands for Transcutaneous Electrical Nerve Stimulation. The main purpose of this, from the name itself, is to help stimulate the nerves so that pain can be removed. EMS stands for Electrical Muscle Stimulation. The main goal of this is to help stimulate the muscles.
There are a lot of people who would need to undergo treatment with the help of this machine so that they can improve and strengthen their muscles enough that their muscles will be able to support their movement again. These are machines that are normally used for rehabilitation.