[quote]Chad Waterbury wrote:
KEY POINT: fatigue and failure are not synonymous: failure is due to fatigue, but fatigue can occur without failure. Fatigue is simply defined as an inability for a MU to perform at it’s highest capacity.
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This IS a good point.
Chad, would it be fair to say that when the speed slows (indicating that the HTMUs have dropped out), you’ve essentially reached failure for the HTMUs?
[quote]Chad Waterbury wrote:
Dark_Knight wrote:
Chad Waterbury wrote:
You DON’T recruit high threshold MUs at the end of the set when your force is low.
This is what confuses me. This says that Zatsiorky was wrong, and the repeated effort method does not touch the HTMUs. Doesn’t the repeated effort method state that the HTMUs can be called on as a last resort, provided that there is a certain minimum load (like 70-80%)? (The RE method confuses me anyway, because it goes totally against my understanding.)
I came into the this thread with the following understanding:
1-The size principle states that the smallest MUs are recruited first
2-As the load increases closer to maximum, the number or MUs recruited increases.
3-The more powerful MUs are recruited as the load becomes heavier
4-A certain load MUST be attempted in order for the HTMUs to be recruited
5-Merely exhausting a muscle will not recruit all MUs (so the repeated effort method CAN’T recruit the HTMUs)
6-In the final reps before failure, the HTMUs have dropped out, leaving the smaller, more enduring (but weaker) ones to handle the job. Since they are weaker, is part of the reason why the final reps are more difficult.
7-HTMUs CANNOT be recruited as a “last resort” because the size principle would preclude this from happening. If they weren’t recruited at the beginning of the set, the load was not heavy enough to activate them in the first place, so they will never get involved. The smaller MUs must handle the job themselves.
The RE method CAN recruit your HTMUs provided the lifting speed is as fast as possible and the load is sufficient (>60% of 1RM).
Where I separate from other RE method recommendations is at the end of the set. When you push to failure you’re overloading your smaller MUs. In some cases (muscular endurance) that can be a good thing. But for maximal size/strength it’s not optimal, in my opinion.
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Wouldn’t it stand to reason, though, that if when your speed slows down you begin to recruit lower threshold motor units in heavier, faster sets, that a lower weight higher rep set would also begin to recruit some higher threshold MU’s toward the end of the set?
Again we can experiment with this stuff. If we have HTMU’s in the tank after a medium-low weight set taken to failure, we should, by that rational, be able to lift a heavy weight immediately after, right? I may give it a whirl.
[quote]Chad Waterbury wrote:
Lorisco wrote:
Chad, I think I need to just outline the process as I understand it and have you show me where I’m wrong:
Using the size principle; you recruit small MU’s and then HTMU’s as the force required increases.
Fast concentric rep speed requires a lot of force, which in turn requires more HTMU’s.
Once the HTMU fatigue (after 15 seconds), you are left with the smaller MU’s and that is when rep speed slows.
After rep speed slows you cannot exert enough force to recruit the HTMU’s unless you rest to allow them to recover
If you continue reps after rep speed slows you are only working the small UM’s, which do not have the potential for increases in hypertrophy and strength like the HTMU’s.
Multiple sets of reps until rep speed slows are required to get enough volume to induce increases in strength and size
If this is correct, I have a question; if you perform fast rep speed sets to failure, will your small MU’s gain in strength and size as well? From a pure hypertrophy standpoint, wouldn’t it be advantageous to work all MU’s, not just the HTMU’s?
Points 1-6 are exactly right. Your question, at the end, is where your confusion sits so I’ll answer it.
You can gain size and strength by overloading the smaller muscle fibers. This is why cyclists have very large thighs - proof that you can hypertrophy the smaller muscle fibers.
With each rep that’s close to maximum force capacity, all of your recruitable MUs are recruited. The largest MUs drop out when you fatigue. Your question is “why don’t we make the smaller fibers drop out too?” The reason, as I mentioned in an earlier post is that it limits your ability to once again reach the largest MUs (ie, generate maximum force) in subsequent sets. Therefore, subsequent sets continue to overload your smaller muscle fibers.
You WILL induce enough fatigue to the smaller MUs to derive strength and size gains if you simply stop when the largest MUs have dropped out. This is where my set/rep guidelines came from. Just because you’re not forcing your smaller MUs to drop out doesn’t mean they can’t grow. Remember, you can’t selectively recruit your largest MUs - all other MUs are along for the ride and they’re contributing to your force output. But if you do overload the smaller fibers to the point where they drop out you’re gonna have a helluva tough time reaching your largest MUs on subsequent sets.
KEY POINT: fatigue and failure are not synonymous: failure is due to fatigue, but fatigue can occur without failure. Fatigue is simply defined as an inability for a MU to perform at it’s highest capacity. If you performed 20 sets of one rep with 85% of your 1RM at max speed you’d recruit all of your MUs with each rep. And if you analyze the force generating capacity of the smaller MUs after that session you’d see that it’s lower. That’s becasue the recruitment of the smaller MUs along with the largest MUs was sufficient to fatigue the smaller MUs.
Hope this helps.
I encourage you all to spread this information. If you do I’ll be forever grateful because it’ll help keep me off the forums. That way, I can devote more time to writing articles where thousands of people can read what I’m saying. [/quote]
Thanks Chad. I appreciate you taking the time to explain this. I’m sure you know it goes against most of the “gymlore” we hear everyday and even some well known trainers on this site. So it is understandable that you will continue to get questions. But I will try and set people straight, now that I have is straight.
Thanks again.
Lorisco