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If you’ve ever been hooked up with electrodes that make your muscles twitch, chances are the treatment occurred in a physical therapist’s office. But recently, small stimulation machines that deliver an electrical current, often called e-stim for short, are becoming commonplace at event expos, health fairs and sporting goods retailers—with home use as the goal.
We’ve seen a proliferation of these devices, but we were curious…do they really work? If so, how does a runner know if she needs one? We turned to a couple of experts: NYC-based pain specialist Dr. Febin Melepura and San Diego physical therapist Chelsea Best to get some answers.
How do e-stim machines work and how effective are they?
They deliver electrical stimulation, which can reduce pain and increase blood flow, but how much of a difference they make varies based on the situation. There are two ways they tend to work: You may see NMES (neuromuscular electrical stimulation) or EMS (electrical muscle stimulation), which means the therapy is designed to stimulate motor neurons—“the nerves that control the muscle,” Dr. Melepura explains. Whereas TENS (transcutaneous electrical nerve stimulation) units are designed to stimulate sensory neurons, aka “the nerves that transmit the pain.” Physical therapist Best explains the former (NMES/EMS) is intended for “someone having trouble contracting the muscle itself.” For example, after a knee injury, it could help prevent atrophy in your quad muscle. TENS, on the other hand, is used only to reduce pain.
How do home ones differ from what pros use?
“While there are many electrotherapy devices available, their basic function is the same,” Dr. Melepura says, as is their efficacy. “Some stimulators are simplified and have preset stimulation settings (frequency, amplitude and duration) for different body parts. The user just pushes a button that corresponds to the part of the body that they want treatment for.” Best says the in-office machines may have more potential settings—but a simple device, even one that only offers TENS, is suitable for most people for home use.
Should a runner who has recurring issues, like lower back pain or Achilles tendinitis, use this therapy?
“People do tend to self-medicate,” Best says. “If you read the directions and you understand what’s going on, they can definitely be very beneficial. In our practice, it’s commonly used as a modality at the end of [one day’s] treatment, because a lot of times people have increased pain, and it calms everything down so that they feel better.” For in-office patients who say e-stim is particularly beneficial, she has recommended a home unit.
If a runner tweaks a muscle or has some acute pain, does it make sense to use e-stim without seeing a doctor first?
It’s up to the individual, but Dr. Melepura says, “The best initial treatment is rest, applying ice or cold compresses and elevating the injured body part. Some injuries will need additional treatment, so if the pain persists for a week to 10 days, individuals should seek the care of a physician who will be able to recommend if electrotherapy is appropriate.”
Should a home treatment feel the same as with a professional?
Yes. Since you can crank up the electrical stimulation on your own, Best says, “You want it to be a moderate feeling but not painful or uncomfortable.” She also suggests treatment for 15 to 20 minutes at a time, and you can use ice with it to help reduce inflammation.
We found a lot of different machines, so here are three questions to ponder:
- Do I want both the option for EMS (for acute injuries) and TENS (to reduce pain)?
- How important is ease of use and would I be apt to try this without professional advice?
- How much do I want to pay? We found a simple TENS unit as low as $17 and a combo EMS/TENS unit around $70 through TENS Pros.
Dr. Melepura offers these tips.
- TENS and EMS should not be used on vital parts, such as across the neck, chest or brain (and not at all if you have a pacemaker).
- Electrical stimulation should be used with caution during pregnancy or when trying to conceive.
- There is a potential of skin irritations and possibly burns if used excessively.