Electronic Muscle Stimulation

Q: What is your opinion of electronic muscle stimulation (EMS) as well as the new electric stim ab gizmos that are so popular today?

A: Okay, let's start with the first part of your question. Four applications of EMS include:

1. Strength - 10 sets of 10 seconds high intensity followed by 50 seconds of rest is Kots' protocol used by Francis and others to promote strength gains (of up to 20%)
2. Recovery - at low intensities, EMS provides a "massaging" effect facilitating removal of waste products and delivering nutrition to the muscles through an increase in local blood supply (Siff & Verkhoshansky)
3. Rehabilitation - will retard atrophy and maintain strength by providing neural input to muscle and can relieve pain and reduce spasm (Siff & Verkhoshansky)
4. Assessment - since EMS recruits white fibers first, a fast-twitch dominant muscle will activate at lower intensities (Lindsay)

For a more detailed description of EMS refer to the following articles:
1. Macrocurrent and Microcurrent Electrostimulation in Sport by Dr. Siff
2. The Truth About EMS. Electronic Muscle Stimulation: Facts and Fallacies by Charlie Francis

As well, two excellent books to read on this subject from the same authors mentioned above are:
1. Francis, C. "Training for Speed." Australia: Faccioni Speed & Conditioning Consultants, 1997.
2. Siff, MC, Verkhoshansky, YV. "Supertraining (4th Edition)." Denver, CO: Supertraining International, 1999.

Now, problems with ab stim machines that are currently popular include the following:

  • No abdominal machine has ever been proven to be more effective than conventional training.
  • These machines are deceptive in that the transient effect of localized water loss gives the appearance of weight loss, but this is short-lived once re-hydrated. From Supertraining, 1999: "Low-intensity EMS can rapidly reduce swelling ... its effectiveness may be due to the pumping action of muscle and/or the creation of an electric gradient across the cell membranes, which triggers the lymphatic system to absorb excess fluid." (pg. 211)
  • Remember, you cannot spot reduce; you must train the entire system (not just one area.) With that said, it is far better to do a set of 20 squats that works almost every muscle in the body than to do as many as 200 sit-ups or even receive up to 2000 twitches from an EMS unit for that matter.
  • Also, prolonged application of submaximal EMS can increase muscular endurance but it will not promote hypertrophy. As you know, the more muscle you have, the higher the metabolic rate. Furthermore, I have seen no studies which indicate that EMS at any level will facilitate lipolysis or fat-burning. Adaptations from EMS are very different from those of voluntary contractions - the infomercials make you believe otherwise!
  • Far too many people are looking for an easy way out, a magic pill if you will. Although enticing, sitting on your couch watching reruns with a bag of chips in one hand, a pop in the other, and some electrodes connected will do nothing to your bulging midsection. It comes down to diet and exercise, plain and simple!