Carbonized Rubber Electrodes Best for EMS & TENS

Factors influencing quadriceps femoris muscle torque using transcutaneous neuromuscular electrical stimulation.Physical Therapy. 1991 Oct;71(10):715-21; discussion 722-3. Lieber RL, Kelly MJ.

Abstract
Quadriceps femoris muscle torque was measured in 40 subjects during transcutaneous neuromuscular electrical stimulation (NMES). Three different electrode types (carbonized rubber, sponge, and adhesive) were used on each subject, permitting determination of the factors that influenced the magnitude of quadriceps femoris muscle torque induced by NMES. This goal was accomplished by entering the various factors into a multiple-regression model. The electrodes differed significantly in their characteristics. The carbonized-rubber electrode delivered the greatest current with the lowest impedance, resulting in the highest knee extension torque. We found that the most important factor in determining torque generation level was the quadriceps femoris muscle’s intrinsic ability to be activated (as opposed to electrode size, current, current density, or skin impedance). These data suggest that NMES efficacy is primarily determined by the intrinsic tissue properties of the individual (defined in this study as “efficiency”) and is not dramatically changeable by using high stimulation currents or large electrode sizes. The precise physiological basis for interindividual differences in efficiency is not known. [emphasis mine]

My comments:

This was one of those things I figured out the hard way during my year of electric stimulation, only to find research from 1991 had already been there. These researcher compared carbonized rubber electrodes to sponge electrodes and the sticky self-adhesive gel electrodes that generally come free with an EMS or TENS machine.Chad's favorite EMS/Tens rubber carbon electrode size

The results of the sponge electrodes were about as good as the sticky (that’s what I call them)  electrodes, but the size of the sponge electrodes were about half the size so I don’t think they got a fair comparison. Since sponges always look dirty to me, I don’t use them anyway, so no great loss. The big difference (which I definitely agree with and think I can feel myself) was that the rubber electrodes, for which the size was comparable (109 cm square rubber, vs 104 cm square sticky), were almost twice as good as the sticky ones. Under otherwise identical conditions skin impedance with rubber was less 53 vs 98 k-ohms (84.9% better), % of maximal voluntary contraction was 21.2% rubber vs 12% sticky (76.7% better), and subsequent quadriceps torque produced was 33.5 vs 17.9 N-m (87.5% better). The idea being that skin impedance is about half as much with the carbonized rubber electrodes, making the electric stimulation about twice as comfortable, so you can activate almost twice as much muscle, producing almost twice as much torque, thus generating a better training effect. Their findings were something I largely figured out on my own, but it was good to see numbers and an explanation put to it.

 

If using the electric stimulation for pain control (TENS rather than EMS) the rubber carbon electrodes should still let you more comfortably handle higher levels of electric stimulation, and I would expect greater reductions in pain per the . This would in turn go along with other researchers finding where EMS reduced pain better than TENS.

Other reasons I like the carbonized rubber electrodes is that they are easy to clean between patients while the sticky electrodes just look like bacteria traps to me. The carbonized rubber electrodes Largest rubber carbon electrodes Chad likes for circulation.work fine, even if with greater amounts of body hair, and the carbonized rubber electrodes seem to last indefinitely (longer than a year with repeated

daily use thus far) while the sticky pads don’t last near as long. though a periodic spray with a water bottle helps extend the life of the sticky pads. The downside of the carbonized rubber electrodes is that they don’t stick to you so they have to be held in place with straps, which depending on the location can be lesser (legs, arms, core, feet) or greater of a challenge (chest and shoulders). Still, for clinical use or home for myself and pretty much every patient I get a EMS machine for, carbonized rubber is THE way to go. My preferred size for most uses being ~4 inch or 10 cm diameter circular pads. For conductivity I just spray them dripping wet with tap water.

Updated 1/25/2016

As always, if you have any further questions or need for clarifications, please don’t hesitate to ask. Being aware that some of my blog ideas are contentious and occasionally a bit out of the field of my expertise, I encourage my readers to come forth with any questions/comments that are of interest or concern. Your comments are valued and welcomed.

Chad Reilly is a licensed physical therapist, located in North Phoenix, practicing science based medicine with treatment protocols unique and effective enough to proudly serve patients from Phoenix, Scottsdale, Mesa, Chandler, Tempe, Peoria, and Glendale.

10 thoughts on “Carbonized Rubber Electrodes Best for EMS & TENS”

  1. Chad, I’ve enjoyed reading your blog and want to pick your brain a bit.

    I used carbon electrodes in school (graduated in 1996) but haven’t used them since. The convenience of disposable electrodes has been the option of choice. But with a new machine I recently purchased, carbon electrodes with sponges were included. I’m a bit rusty on the technique and it is challenging to find info on-line as to application protocols for using that type of electrode. What type of carbon electrodes do you use? Do you use a sponges with them? Do you ever use gel? Do you use disposable barriers of any kind for “sanitary” reasons?

    Thanks!

    • Hi Debra,

      Sorry for the belated response, it took me a while to figure out how to add photo’s to my blog, but the green pads are what I use for >95% of my applications of both EMS and TENS. I had to buy a thousand pairs off alababa.com to get a deal on them.

      Occasionally I will use even larger pads ~5×8 inches for circulation/aerobic conditioning, which are the largest electrodes I have seen commercially available. They have the advantage in that they feel great and you can cover a lot of muscle with them at the same time with minimal channels. However, that’s also their weakness. With them being so large, you need a very powerful EMS/TENS machine (like the Globus) to power them. For quadriceps, for example, I noticed on myself that I got a better workout using two channels with the 4” circular pads (4 electrodes) than one channel (2 electrodes) with the 5×8” pads.

      I don’t use the sponges as I found them difficult to clean. I don’t use the gel because I don’t want the mess or expense. Water without the sponges works great, is free, with nothing to clean up afterwards. You just want to make sure they are very wet, for which I use a spray bottle. Electrodes with the stippled surface do seem to hold the water better, but the most don’t have the stippled surface so that limits your size choices a bit, but the smooth ones are still pretty good.

      For cleaning between patients we use soap and water. It’s probably not 100% sterile, but when I tried alcohol, Clorox, or other disinfectants every time I wiped the pads clean “black” came off on the paper towels, and the pads eventually stopped working. So I think it was breaking down the rubber/carbon compound. Since I went to just soap and water, my pads have lasted two years of heavy use and they are still going strong.

      One thing I have noticed with a lot of EMS units sold, is they often come with good electrodes, the exact ones I like, but the straps are all but worthless. My photo shows the straps I had made which are 4” inches wide to fully cover the electrodes. I had to order those in bulk for my patients also, so if you want some, feel free to call or email my office about those. My web guy is working on setting up a web store with some of my favorite products, but I’m not sure how long till he finishes. I hope that helps, and I hope this doesn’t come across as a sales spiel, but I found that good electrodes and particularly good straps are hard to come by, so I had to come up with a package deal for my patients who want to do EMS at home without sending them to multiple websites.

      The 3.5” electrodes I have for $10 a pair.
      The 5×8” electrodes $20 a pair.
      The straps I had made up are $5 a piece, and with my 4 channels machines I usually recommend 4 straps. which gives enough for both arms or legs at a time, or connecting two together most people can work core or shoulder.

  2. Hi Chad–since I’m the only one using my EMS and since I also have RSD/CRPS in my feet and ankles and cannot tolerate a lot of stim intensity, is it thus ok to use the sticky pads? Do they make bigger sticky pads than the ones included with the Genesy 300 Pro so I can use them on my back? Thanks.

  3. Hi Chad,
    Very interesting article again and I definately wish to purchase some of these rubber pads with stippled surface. I am writing from the Netherlands, Europe, and I have not been able to find a shop, webshop where they sell these.
    I also experience discomfort and stinging sensations when running EMS 10/50/10 and where intensities are going above 70mA.
    How is it going with your webshop? I would really like to buy the two types as shown in the pictures in this above article.
    The circular green color ones and also the square shaped larger ones with pink color.
    Thank you in advance. Best regards, Thomas

    • Hi Thomas,

      I just had my office check and it looks like we could ship our electrodes and straps to you through the US Postal Service for a reasonable price. I’d email my office at absolutept@hotmail.com and let them know exactly what you want and they should be able to figure out an exact price including shipping. Good straps are harder to come by than pads as I had to have mine custom made. Larger electrodes like my green ones, very wet with water, and held tightly in place with full contact elastic straps should minimize the stinging feeling. Sometimes with higher levels of stimulation you still feel it, but it’s a lot less than it would have been otherwise. Overall the shop is moving forward, though it’s kind of a learn as we go thing.

  4. I’ve been using TENS machine for years when my lower back flares up, I recently had a flare up and had a terrible reaction to the self-adhesive pads. I purchased the rubber carbon pads and gel but it did not include instructions on how to clean them, will soap and water take the gel off without damaging the pad?

    • Hi Bev,

      Honestly I never use the gel with rubber carbon electrodes, I just spray them with water. I would imagine that the gel is water soluble, so soap and water should clean them up fine. In the office we always wash them with soap and water and they have been lasting 3 years and counting. At home, since my machine is only used on me, I just spray with water, and use them like that. I tried the gel a couple times and it just seemed like a costly mess that didn’t help much.

  5. How may I use long lasting rubber carbon pads with wireless TEN unit? It would be used on low back to control pain.
    It would be fantastic if you could provide me with such pads..

    • Hi Wolf!

      You might be screwed. Do you have the Compex wireless machine? If so I’m not sure you can attach rubber carbon electrodes. I have a ton of electrodes still in my office but they need to be plugged into 2mm pin wires, which are the most popular. If your machine has 2mm pin attachments then you should be good but if it’s a Compex I bet it has proprietary snap electrodes. Interestingly I bought a wired Compex machine to test out because their price had come down several hundred dollars to test against my Globus units. Well I got ripped off! I knew the Compex units used snap electrodes, but they also sell a 2 mm pin electrode set to go with their machines so I can use any electrodes I want. Well it turns out their own pin electrode wires that they are still selling are incompatible with their new machines so you are stuck using their proprietary snap on electrodes. Worse is their snap on electrodes have a protuberence in them so they won’t stick to other brand snap on type electrodes. Still worse when I called to return the wires that were not labeled as incompatible they refused to pay return shipping. So I said I would just keep it all and blog about my displeasure (that you’re reading now). I think they lowered their price on machines knowing they could upcharge people on electrodes, which from what I can tell don’t last any longer or work any better than lower priced sticky electrodes and are definitely inferior to rubber carbon electrodes.

      If all that is the case I’d recommend getting a programmable Globus Genesy 300 Pro, or Globus Triathlon. Also EMS/TENS is only a partial answer for back pain so I would encourage you to check out some of my back pain blogs, or Spinal Flow Yoga, where I’m incorporating the exercise and postural advice into a full fitness program you can do at home without my gym. The website still needs some work but the exercise program is up in a learnable way.

      I hope that helps!

  6. Hi Chad,

    I sent an email to your office 2 days ago checking to see if you still sell your preferred electrodes and straps. Hoping to purchase a few so if someone could contact me when possible it would be great.

    Also, I’m very interested in your tens/ems training on abdominals. I’ve been lifting for 10 years now with a focus that started on strength/power-lifting, but has moved more into physique. My abs have been underdeveloped compared to the rest of the body and I was thinking of using tens/ems to change up the training and potentially get better results. Can you summarize your frequency of training and length of program time you had been doing for abs?

    Appreciate all the awesome info on your blog and videos!

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