T.E.N.S. stands for Transcutaneous Electrical Nerve Stimulation. The key here is the NERVE part. TENS is a “pain blocker.” The buzzing sensation is thought to block the pain signal from the nerve to where it is perceived in the brain as pain. T.E.N.S. units are also thought to aid in the release of endorphins, which are the body’s natural pain fighting mechanism.
NMES, E-Stim or Muscle Stim stands for Electrical Muscle Stimulation or NeuroMuscular Electrical Stimulation. The key here is the waveform that it outputs is different than that of a T.E.N.S and it affects MUSCLE. T.E.N.S. simply blocks pain where muscle stim targets muscle to prevent retardation of muscular disuse atrophy, relaxation of muscle spasm, muscle reeducation, increasing range of motion, increasing local blood circulation, and as an immediate post surgical stimulation to prevent venous thrombosis. In addition to having a different waveform, it also has what is called “Timing Options” including Ramp ON/OFF times, “ON/OFF” times and sometimes a “Delay.”
The ramp times are the amount of time that the unit takes in each cycle to ramp up to the maximum intensity. The ON TIME is the time that the intensity is on in each cycle and the OFF Time is the amount of time the unit is off in each cycle. The cycle repeats. This causes a muscle to slowly reach contraction (RAMP ON), stay contracted for a short period of time (ON TIME), slowly release the contraction (RAMP OFF) and then rest before the cycle repeats (OFF TIME). The timing options make it possible for the muscle stimulator to do a “pseudo exercise” for the weak muscle.
In conclusion T.E.N.S. units effect NERVE endings and are used for PAIN RELIEF.
Muscle stimulators affect MUSCLE and are used to rehabilitate muscle.
Each has a different waveform and the Muscle Stimulator has TIMING OPTIONS, whereas the T.E.N.S. does not.
Ask your doctor which modality is right for you!