I’m concerned that you guys are using incorrect stimulation parameters.
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[li]Your frequency is off;
[/li][li]Your pulse width is off;
[/li][li]Your rest is too long;
[/li][li]Body part determines pulse width, it does not determine frequency;
[/li][li]The training goal determines frequency.
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And RB34, if done properly, you will get strong training contractions without hurting.
Where do I find Charlie’s description of EMS usage?
Andrew
Bench 5x3x150
Triceps 2x6x70,80
Pulldowns 2x6x190,205
Andrew used EMS today. We used 80hz. Width was 300. He found he could raise the amplitude higher with the higher hertz, and it was more comfortable. His hamstring contractions weakened after 6 reps.
Matt will use it tonight.
Paul is now training fulltime with his University track team. Kalynn is fully invested in work right now. Hopefully they will be able to join us again soon.
[ol]
[li]What were his actual and previous current intensity (amplitude)?
[/li]
[li]If his previous Hz setting was 35 Hz and now it is 80 Hz as you reported, these are training settings for rather different goals (aerobic resistance vs. maximum strength). What’s Andrew’s EMS training goal?
[/li]
[li]Was his work/rest time 10/50 seconds?
[/li]
[li]Why don’t you go above 300? Globus and Compex for upper leg are programmed at 400 microseconds pulse width duration (chronaxie), and 300 seems way below optimal; using the appropriate width for hamstrings, it allows one to get a stronger contraction for the same current intensity (amplitude), or to decrease the current intensity (amplitude) for the same contraction, thereby increasing the comfort.
[/li][/ol]
[ul]
[li]Since your training goal is Maximum strength, I recommend to keep frequencies between 75 and 100 Hz. []In addition, with 300 microsecond pulse width duration, it’s not possible to adequately stimulate upper leg muscles; for sure a good portion of the muscle fibers of the stimulated muscles are not trained well. My recommendation would be to upgrade to a unit that goes up to around 450. []You also need a unit that displays current intensity in milliAmps (mA) and that goes to at least 100 mA. The Globus goes to 120 mA, the Compex goes to 100 mA. Not that you will ever get to 120 mA, at most 60 mA will be required. But with a 120 mA maximum you would be able to use split cables that double the number of pads, allowing the positioning of pads on more muscle strands at the same time.
[/li][/ul]
Actually this range is not my recommendation, but it comes straight out of EMS research. The frequencies between 75 Hz and 100 Hz are those that progressively recruit more and more fast-twitch fibers of type IIb into tetany. So when you start training for maximum force you would start at 75 Hz, and then after a couple of weeks you would move up to 80, 85 Hz and so on, up to 100Hz.
The unit has two channels, each going from 0-100mA.
I see the unit is a IF-7500; besides the limitation in pulse width, you do not have a dial telling you the current level. So you will never know your real mA current intensity, until you graduate to a more serious unit. The specifications in the site you gave me are not clear, but it appears that the unit does not deliver the 100 mA promised. I find difficult to believe that the level 6 you have reached corresponds to 75 mA (if you do the proportion, 6 * 100 / 8 = 75). The manual says that the unit delivers 100 mA under a 500 Ohm load, but actually upper-leg muscles represent a load between 2000 and 3000 ohms, so the real mA output would be 1/4th to 1/6th less than what you’d think.
Interesting. And what about hertz above 100hz? What effect does such a setting create? Regardless of the actual mA, we can certainly feel the contraction!
Good observation! Frequencies above 100 Hz are normally labeled (Globus and Compex) explosive strength training. Any value above 100 Hz certainly still activates fast-twitch type 2b fibers.
However, these frequencies would be further away from the frequencies (sufficient to cause full tetany) of fast-twitch type 2a, and slow-twitch type 1 fibers. So I believe that the rationale here is that it would convert some of those fibers into the higher type.
Research has shown that there is some plasticity in the muscle fibers: if subjected long enough to another type of stimulation they would start changing their properties: capillarization and energy conversion mechanism. A strength and conditioning trainer is the best judge of whether the athlete needs to work on explosive strength.
Thanks! They are both pretty big PRs for us. However, I am worried that they might not be giving the best effect, and I am considering moving to the back squat in the future. I am wondering that, as the weights go up, and the lower back becomes more involved with these athletes, that the same motor units will not be hit, and what repercussions will take place…