This is an email I have exchanged with a Neurotrac representative. I had told him about the false advertisement of the unit claiming to be able to have 450uS when the unit really only gets 330uS.
[b]"We deeply apologize for misconception of advertising, our other product called Sports has 450uS and Sports XL had always 330uS max.
We had a mistake on our Sports XL manual and this mistake (450uS was mentioned) was corrected in 2008-1010, since then we clearly display 330uS as per correct technical specifications.
In fact, Sports XL has much stronger symmetrical pulse comparing to Sports, therefore 330uS in Xl are comparible to around 360uS in other asymertical waveform units.
Let me suggest that uS and mA are directly proportional in terms of power to muscle, so the stronger contraction by mean of electrical power, you can eithr increase by uS or mA. for example, a pulse of 330uS and 40mA will have exactly the same contraction effect as a pulse of 660uS and 20mA (as the power=[mA x uS] delivered to the muscle is the same).
This means you can still use the pre-set programmes or your own custom, and increase ma until the level of contraction."[/b]
What do you think of the statement above? Is it accurate according to your expertise on EMS Max Strength?
EDIT - In the comments above he’s distinguishing the difference between the Neurotrac Sport XL model and the Neurtrac Sports model (an older model).
Ku2u#1,
They do not know what they are talking about. µs * mA calculates the charge delivered (mC or milli-Coulombs). However, muscles obey Lapique’s law (http://bit.ly/Lapique). In a nutshell it means that there is an optimal choice to stimulate muscle, i.e. an ideal combination of µs, also called chronaxie. For quadriceps this is in the neighborhood of 450 µs.
mA determines how deep in the flesh the current will go, and therefore determines muscle fiber recruitment percentage.
Thanks for the response Giovanni. Here is another email repsonse from him regarding the quads needing 450uS.
Me: According to my knowledge the quadriceps muscles need at least 450us for an effective stimulation, is the neurotrac sport XL model capable of coming close to this in comparison to another unit?
Neurotrac representative: “450 on symmetrical or asymmetrical waveform? symmetrical, used in Sports XL is much stronger then symmetrical, used in Sports.
The data source you use for 450uS should specify the waveform and the approximate height of a person. See the attached electrode’s placement manual, page 13: it discusses the uS settings on our symmetrical-waveform machines.
How stronger in comparison - I’ve never calculated as there is clear explanation: with more mA you substitute the lack of power.
Finally, you use higher uS for bigger muscles, the quadriceps of a normal child of 120cm height I would stimulate with 120uS, no more.
450 is not a magical number for any quadriceps, it is just the length of an impulse and if it is 200uS longer or shorter - the mA intensity setting will make up or compensate the difference.”
We are talking about symmetrical waveforms, I don’t know why he would bring up asymmetrical. I agree that the ideal chronaxie for a smaller muscle, a biceps or the quad of a child, is shorter. But for an adult you are going to limit your stimulation. If you need to increase mA to make up for a shorter µs, you are making the stimulation less comfortable, and you are going to keep mA low because it is going to be extremely uncomfortable. Higher µs are going to make stimulation much more comfortable, and you will be able to get better results. Recent studies have shown that the number one determinant of results in EMS is recruitment > 50%. The fact that this guy is trading mA for µs, means he doesn’t understand Lapique’s law.
I’m curious to how you configured the proper chronaxie in microseconds for each area of the body that you listed in your EMS Digest manual:
Lower leg - 430 microseconds
Upper leg - 380 microseconds
Lower Torso - 330 microseconds
Upper Torso - 280 microseconds
Arm - 200 microseconds
Forearm - 230 microseconds
Are these numbers configured from your own experience or is there research/evidence behind the explanation of these number? I’m also curious to how you came up with 450 microseconds being efficient for an effective quad stimulation.
Now this is good information! If anyone is going to spend serious money on an EMS unit, I want to know why, and this is helping. I’m still not sure how big of a comfort difference there is between 330 microseconds and 450 microseconds considering this only applies to one muscle group as related to max strength.
Is there any reason that the top units (e.g. those with 8 electrodes) don’t allow custom programs? Is this a safety / certification issue in North America? If so, will manufacturers input programs of my choosing as standard?
With regard to some units having 6-10 seconds on, 50 off protocols as standard, I haven’t carefully researched EMS units recently, so if there are commercial units available it would be nice to know about them.
T-Slow,
The best way to understand the difference between different µs waveform duration, is to use a machine in which parameters are adjustable on the fly (while one stimulates). We have one such unit, and the reason we put it on the market was for people like coaches who need to experiment, make changes to adjust for comfort, or to increase the force developed at each twitch. We also developed a machine with 10/50 work/rest protocols, and variations around that concept to help athletes go on a progression. I think I have to stop here because more would be considered marketing.
I also wanted to respond to a statement you made earlier about your loyalty to the protocols espoused by Charlie Francis. When Charlie started using EMS, the waveform he employed was the Russian waveform, which is equivalent to a waveform of 200 µs (or less) at 2500 Hz. Later on he started employing waveforms of longer duration, moving to square wave (aka symmetrical, biphasic rectangular). So you can see that he was for progress and change, as new things are proved with facts to work better. When he asked to review one of our machines, I sent to him one of our programmable machines, which had adjustable parameters, 450 µs, and a 10/50/10 protocol programmed in it. He liked it very much, and responded: “BTW it’s a great machine”. I’m sure he would have all been for making even more progress and putting in a machine variations around the 10/50 s rest/work protocol to help athletes’ adaptation and growth.
t-slow: how did you go about avoiding or getting over these deficiencies, especially in the quad area it seems. I injured my pcl several years ago and whenever I stop squatting heavy it flares up again with sprinting, so i’d be using the ems to keep my quad strength up/supplement quad strengthening to prevent pcl pain
gciriani: do you have any specific recommendations in the not super-expensive range (obviously I don’t need anything super advance but obviously I want something that gets the job done)? you could pm me or I could give you an email if you’d prefer…
Originally posted by tb2010:
… do you have any specific recommendations in the not super-expensive range? …
tb2010,
I understand the difficulty you and others are having, trying to make sense of disparate advice. In one camp you have people like me who have a conflict of interest with the product they sell, and therefore you would not be sure whether to trust the advice or not. In the other camp you have people like T-slow who have had experience with the lesser machines only, and therefore cannot offer a direct comparison either.
The only thing I can offer you is a more informed opinion by NumberTwo (aka Derek Hansen), who has contributed many posts to this forum. Although NumberTwo has an interest in promoting my brand, he is the only one I know of in this forum who has tried and compared machines going from several thousands to less than a hundred. Following is his quotation.
Originally written by NumberTwo:
On the subject of cheap stimulators - I’ve had a bunch (3 to 4 stims) in the past. They were cheap on many levels. Less comfortable stimulation, cheaper build quality (i.e. timers and knobs fell off), leads wires would break and no ability to manipulate pulse width. These stimulators did not have pre-set programs, but they also lacked the convenience of warm-up modes, cool down, pause function, etc. Tough to convince people that we simply support Globus because it is a much superior product.
For what it’s worth, I have tried dozens of units over the years ever since reading the CFTS back in 2001 trying to emulate the success without spending money, I mean no money! From £5 - £35 even units like the body tech elite (“elite” lol) for £100 with fixed programmes, fixed frequencys and widths the lot
As I said earlier I went only a little more cost £155 with my elite pro 2 bought 4 years ago now, in this time I have used on myself and my athletes (one of whom is now with uka and ran 10.35 under me)
I won’t be changing that’s for sure, the contractions are full and strong without that feeling of electrocution I was getting with other cheaper models.
so all in all it looks like for ems its something that if I want quality I need o be willing to spend some cash. on the one hand, superior quality would probably also speak to longevity so even if I have to deepen my pockets a bit, I probably plan on doing some bodybuilding if not moving towards oly lifting when my track career is over, since I enjoy the weightroom portion of speed development so much, so I could be using it for years to come
on the other hand the only money I will have for the next school year and next summer (I will be taking classes) will be the money I make this summer, so the more I spend now, the less I’ll have for college things and other track stuff (though hopefully I’ll eventually run fast enough times that our school’s sponsorships (used to be nike, but a new contract is being negotiated) will just give me shoes (10.93 or 7.00 in the 60).
gciriani: even with conflict of interest, what models would you recommend as far as what I should be looking at? obviously I can’t throw down the type of cash a professional would. I am 19, a mid 11 100 runner, with a 3 foot vertical and can squat 2.5x my bw to parallel as far as stats go
a-j: does the elite pro 2 have any of the problems that were discussed earlier in the thread? and yeah, I’m no 10.35 runner, hahah
and I have cfts, btw, as far as my knowledge of how to use ems. I also got a bit of experience with them as a soph in hs during the fall (my 55m pr at the time was 7.23) while doing pt for my left pcl for some quad strengthening
a-j,
You have the right idea and you have found something that is working for you. Charlie never had any money when training his athletes. People have this idea he was so high tech but his real expertise was in how creative he applied the key principles of proper training. He never had anything fancy to work with in terms of any equipment. It took him a long time to generate money and when he finally did he spent it having people work for him to improve the performance overall for the group.
If you have a stim that is working stick with it.
Originally Posted by tb2010
What models would you recommend as far as what I should be looking at?..I can’t throw down the type of cash a professional would…
… does the elite pro 2 have any of the problems that were discussed earlier…?
tb2010,
I have to partly echo what Angela wrote. EMS is not a panacea, and is not for everybody. For some it can help; for others it won’t necessarily produce results. The Globus Elite models are good units. We are not importing this model in the USA because the small market demand in North America, would not even cover FDA certification costs.
for the parameters stipulated within the EMS theory thread, my unit hits the marks. add the capacity to make my own programmes (same as charlies config) I actually like it.
Though its at the lower end of the elite spectrum of machines, as i said it covers what is required and isnt that expensive
as for build quality, my athletes call it the ‘car jacker’ as it feels rugged and loks like it could power a car lol
Every athlete starts somewhere, my lad went from 10.9 to that run in 18 months now im trying to replicate with my new youngsters lol
That unit does have great parameters but it only has 4 electrodes that can be used at once. Nothing wrong with that but it just means that it will take twice as long to do the work. It will take at least an hour to stim 5 body parts with 8 electrodes if you use Charlie’s protocols of 10/50/10 or 5/55/5.
Yeah that is true, I could have plumped a few more quid for the better pro 4 but at that time it was all I could realistically afford for something that I hadn’t had succes (as used cheaper commercial products)
I’m just used to the time it takes now tbh, sometimes I will just stim whilst watching tv… I guess you just gotta make the best with what you got or can get and if that means a longer session then so be it.
At some point I will purchase a better more user friendly unit but I get what I need at the moment
Originally posted by Ku2u#1:
I’m curious to (know) how you configured the proper chronaxie in microseconds for each area of the body that you listed in your EMS Digest manual
Ku2u#1,
Those are based on a workshop I took on the subject. When we configured the programs for North America, we increased those µs parameters based on target users, input of a consultant (who worked both with Globus and Compex), experience and comfort.
How come the pusle width/microsecond varations are listed in areas of the body instead of specific muscle groups? For instance why list upper leg, lower leg, upper torso, lower torso, etc? Wouldn’t the ideal microseconds vary between the quads, hamstrings, and glutes?
now im trying to replicate with my new youngsters lol