THE CORRECT INTERPRETATION OF THE SIZE PRINCIPLE AND ITS PRA

short story - http://versita.metapress.com/content/6m ... lltext.pdf

long story - http://www.scsepf.org/doc/291208/Paper1.pdf

This is a very interesting meta-study on the effect of varying rep ranges on motor recruitment and strength gains. It effectively states that rep ranges don't matter, effort on the last rep does, independent of how many reps were done before.

This overturns what has very nearly become the accepted wisdom in the strength training world.

Below is the conclusion of the paper -

Conclusions and practical applications

• Recommendations to train with very heavy resistance (loads heavier than 6RM), because they purportedly result in superior strength gains, are based on a faulty premise and have very little supporting evidence.

• The size principle, motor unit activation studies and resistance training studies do not support the contention that individuals must train with maximal or near maximal resistance (load) to achieve optimal strength gains.

• Effective resistance training simply requires the selection of a reasonable range of repetitions (based on a personal preference) such as 4-6RM, 6-8RM, 8-10RM, 10-12RM, or 12-14RM, and a progression of the resistance to stay within the desired range of repetitions.

• The level of motor unit activation required to stimulate strength gains is not known. Maximal or near maximal effort on the final repetitions of a set generates maximal or near maximal motor unit activation but may not be required for optimal strength gains.

• The preponderance of evidence strongly suggests that if a similar effort is applied on the final repetition of a set, the resulting strength gains are similar—regardless of the amount of resistance used for training.

Interestingly it seems like many old timers had a similar view on the topic. The general thought being lift weights and keep adding weight and you'll get bigger and stronger. I also like the fact that personal preference is part of the recommendation. I've always thought that temperament plays a large role in training. Some people seem to just prefer certain rep ranges for certain things. Maybe we shouldn't knock those who tend to work in the 10 + range, as long as they are progressing the loads somehow.

I'm curious what others think about this. Is there some central flaw in the 85 studies that invalidate the paper, or are we too worried about rep ranges? What about the corresponding bit of common training wisdom that 10-15 (more or less) is hypertrophy range? Many old timers were doing singles and getting bigger. Is the reason 'accumulation phases' work simply because those ranges also get you stronger, perhaps in a more easily controlled way?

Thank god the study didn't get into how many set are best. That would be too much to take in!

Of course these papers are a few years old, but still new to me.

A friend passed on Mel Siff's remarks on Capinelli's work

Mel Siff's analysis of the Carpinelli study:

"Carpinelli 's study or the "exhaustive study" by Carpinelli and Otto did not involve any comparison of elite weightlifters or powerlifters - in other words, in two sports whose progress is quantitatively assessed under very controlled conditions among athletes who are equally motivated and willing to execute a 1RM, not some submaximal measure, often carried out on laboratory apparatus. Moreover, those studies which purported to accurately compare on and multiple set training did not do so on grounds which permitted any valid cross-correlation between experimental results achieved under very different

conditions with very different subjects. None of those studies either examined ballistic or explosive methods of training, nor did they examine the effectiveness or the lack thereof displayed by 'Olympic' lifting style methods."

Is it another case of sports scientists not knowing their sports? How much do we really know? I throughly enjoy these sorts of questions. I hope asking them doesn't rock too many apple carts.

Good luck for who wanna get OACs doing 12-14 RM.

Hummmmm... I've read (most of) both papers... what does it mean???

It says the resistance used does not matter as long as you go to the last reps needed to activate all motor units (fatigue).

It does not define "optimal" in optimal strength gains!

- is it optimal in terms of total gain?

- total gain per unit of time under protocol?

- total per unit of time under tension?

- or total per duration of workout!

It ignores the energy system used.

It does not define hypertrophy.

Cole, as far a I am concerned, this information resolves one of my own little conundrums. Until now, reading the many questions and discussions about optimal sets+reps here, there and elsewhere, I kept wondering what was wrong with me, never being able to follow the prescribed protocols (low reps with high resistance for max. strength gain), because in my case on “good†days failure follows at higher reps and on “bad†days at lower reps. I can stop worrying now and just focus on what failure really implies.

I have read somewhere (and tend to believe) that a maximum athletic effort uses maybe 60% (??) of an individuals true one-time potential (reached, for example, by a mother lifting a car to free her trapped child). So, the obvious question is, what should that 1 RM effort be relative to that true one-time potential to get these so-called “optimal†strength gains.

That leads to the question what the role is of “motivationâ€, “drive†and an individual’s ability to handle fatigue. “Fatigue†seems to be more of a built-in protective mechanism (giving you a warning sign well before you go into, what we might call, your red zone), but in and by itself it is a very subjective feeling. So, would you have better training results (in terms of strength gains) if you can train yourself to do that last rep with a bearable amount of discomfort (which might be unbearable to someone else) instead of stopping before that happens, or is that a recipe for overtraining and, maybe, injury. Or .... , is the ability to find that individual training limit what separates the winners from the also-rans (in strength gain terms)?

The major flaw is not separating training the tissue vs training the CNS to USE the tissue.

Heavy weights do both. Lighter weights do not, because the size principle only applies to single efforts, not repeated efforts.

The theory of orderly recruitment, AKA size principle, is that as a weight gets heavier the body must recruit more motor units to work simultaneously.

This has, incorrectly by many, been used to say that only heavy weights ensure maximal recruitment. This is patently untrue. The correct statement is this:

"Only a near-maximal effort will train near-maximal synchronous recruitment."

That's very important to understand. Training to failure will recruit nearly all muscle fibers, but it will not be at the same time. That is why you will not see the same 1RM gains with equal hypertrophy when comparing light weight training to heavy: The tissue is there, but the body is not good at using it all at the same time.

Everyone who is familiar with the "Newbie Effect" knows that the vast majority of strength gains in the first 6 weeks is due to the CNS learning to use what is there. You will see the same thing happen every time you switch from focusing on muscle growth to focusing on maximal strength.

Rep ranges matter. Kreiger and Aragon have both decimated this guys work.

Joshua Naterman said:

The major flaw is not separating training the tissue vs training the CNS to USE the tissue.

Heavy weights do both. Lighter weights do not, because the size principle only applies to single efforts, not repeated efforts.

The theory of orderly recruitment, AKA size principle, is that as a weight gets heavier the body must recruit more motor units to work simultaneously.

This has, incorrectly by many, been used to say that only heavy weights ensure maximal recruitment. This is patently untrue. The correct statement is this:

"Only a near-maximal effort will train near-maximal synchronous recruitment."

That's very important to understand. Training to failure will recruit nearly all muscle fibers, but it will not be at the same time. That is why you will not see the same 1RM gains with equal hypertrophy when comparing light weight training to heavy: The tissue is there, but the body is not good at using it all at the same time.

Everyone who is familiar with the "Newbie Effect" knows that the vast majority of strength gains in the first 6 weeks is due to the CNS learning to use what is there. You will see the same thing happen every time you switch from focusing on muscle growth to focusing on maximal strength.

This.

Debate over.

If you boys want to lift pencils to failure, go right ahead.

That pencil comment is actually an excellent segue into a caveat here...

If the weight lifted is not sufficient to cause recruitment of any fast twitch motor units, you'll be able to go just about forever because you will only be using the non-fatigueable fibers. If you're really recruiting all motor units, you'll never have a set last more than 2 minutes, and that's if you're really just barely moving into the fatiguable zone. Normally this will not go past 60-70s of constant tension. If you do, you're only using slow twitch fibers. You will be surprised at how much you can do with just slow twitch fibers sometimes.

No one is talking about lifting pencils, have some common sense. Obviously the argument breaks down at some point. Energy systems come into play etc.

The thing is some people have gotten strong using different rep schemes. Some people seem to prefer certain rep schemes and they get stronger. Some populations are afraid of too heavy, does that mean that a trainer can't work with them?

Slizz, I understand what you are saying, and of course, different rep ranges produce different results, but couldn't we put that under the Specificity umbrella. If you want to get stronger at lifting singles, lift singles, if you want to get stronger at sets of 10 lift sets of ten, but keep adding load. (And another thing that's not mentioned, add some sort of periodization)

I take it that the thesis was all muscle spindles can be used even if not lifting heavy.

Certainly there is something to David's point, as has been discussed before, since for the OAC commonly is a 1rm lift and rarely more than 5rm. Yet, one of the most effective ways to prepare for it is - rope climbing, which is typically a high rep activity.

Anyway for the most part I'm playing the Devil's Advocate here. I'm certainly working in the 1-5 rep range for strength, and particularly with weight naturally prefer 1-3 reps. The thing is I constantly see trainees who just don't feel comfortable with the low reps, though they often change their opinion after a month or so of such training. Also for plateau busting upping the volume is a common technique.

Cole, again thank you for posting the link to this interesting paper. I am learning quite a bit from it (and from the discussion), even if only a part of the total bio-mechanical force producing system is discussed and some definitions are missing (see Fred's post). My excuses for the length of this post, since it served mostly the purpose of letting myself understand the key question a bit better.

Let me see if I can understand the drift of the discussion so far. The paper states that strength gains only occur if the last rep results in the orderly recruitment of (most or) all motor units that contribute to a specific activity; apparently, that degree of motor unit recruitment can only be done once (energy system depleted?), so you need to have repped-to-failure. Therefore, for strength gains, you should train a specific activity to failure; why; because only at failure have you also used the larger complex motor units for force production sufficiently to stimulate growth of your biochemical strength system (??).

Nobody seems to dispute this. The disagreement seems to be about how best to reach that point of failure: with sets of small reps or with sets of more reps. If I understand the biomechanics, then small reps to failure will engage the larger motor units earlier; lower reps will get there in smaller sequential steps of motor unit recruitment. Apparently, the smaller motor units can not recover completely after a rep, so, with more reps, you can reach your point of failure with a lower weight because more of the smaller motor units do not contribute any more to force application (i.e. can not be activated because their energy system is depleted?). So the question seems to be whether sequentially working towards failure of all motor units (engaged in an activity) in a few large steps (of sequential motor unit recruitment) is more effective (for strength training) than working to failure in a larger number of smaller steps.[Question]

Nobody seems to dispute the premise that training protocols using sets of 1 RM are not practical or even not possible because a 1RM simultaneous orderly motor unit recruitment (by the CNS) is very difficult (just watch olympic lifting meets). So, more reps. But according to some, using a small number and according to others, using a larger number. The paper says “our tests have shown that it does not matterâ€.

Looking at it from my short analysis I tend to agree and disagree with this conclusion. Yes, I agree for most athletes who are not looking for optimal results needed to compete at the highest level of the particular activity. No, I disagree for those who want to compete at the highest level.

FritsMB I happy you got something from it. I'm also trying to understand more, our bodies and the world are complex. I don't believe it's a black and white situation no matter, though some methods certainly work better for certain situations than others.

Thanks FritzMB, Joshua and Cole Dano for posting this and the subsequent discussion; at first I did not understand much... I still don't, but I am feeling like I am learning something.

...I am just not too sure what it is! :roll:

FritsMB said:

Cole, again thank you for posting the link to this interesting paper. I am learning quite a bit from it (and from the discussion), even if only a part of the total bio-mechanical force producing system is discussed and some definitions are missing (see Fred's post). My excuses for the length of this post, since it served mostly the purpose of letting myself understand the key question a bit better.

Let me see if I can understand the drift of the discussion so far. The paper states that strength gains only occur if the last rep results in the orderly recruitment of (most or) all motor units that contribute to a specific activity; apparently, that degree of motor unit recruitment can only be done once (energy system depleted?), so you need to have repped-to-failure. Therefore, for strength gains, you should train a specific activity to failure; why; because only at failure have you also used the larger complex motor units for force production sufficiently to stimulate growth of your biochemical strength system (??).

Nobody seems to dispute this. The disagreement seems to be about how best to reach that point of failure: with sets of small reps or with sets of more reps. If I understand the biomechanics, then small reps to failure will engage the larger motor units earlier; lower reps will get there in smaller sequential steps of motor unit recruitment. Apparently, the smaller motor units can not recover completely after a rep, so, with more reps, you can reach your point of failure with a lower weight because more of the smaller motor units do not contribute any more to force application (i.e. can not be activated because their energy system is depleted?). So the question seems to be whether sequentially working towards failure of all motor units (engaged in an activity) in a few large steps (of sequential motor unit recruitment) is more effective (for strength training) than working to failure in a larger number of smaller steps.[Question]

Nobody seems to dispute the premise that training protocols using sets of 1 RM are not practical or even not possible because a 1RM simultaneous orderly motor unit recruitment (by the CNS) is very difficult (just watch olympic lifting meets). So, more reps. But according to some, using a small number and according to others, using a larger number. The paper says “our tests have shown that it does not matterâ€.

Looking at it from my short analysis I tend to agree and disagree with this conclusion. Yes, I agree for most athletes who are not looking for optimal results needed to compete at the highest level of the particular activity. No, I disagree for those who want to compete at the highest level.

Common mistake... Orderly recruitment refers only to single efforts. Recruitment from fatigue is not quite the same, because it is sequential and not simultaneous. The major difference is that recruitment from fatigue seems to result in much more sustained elevation of protein synthesis, and will have a much more even effect on muscular development.

The higher the rep range, the less of the muscle you are actually fatiguing. That's not necessarily a bad thing, it tends to mean that you are A) repeatedly fatiguing only the biggest, strongest motor units and B) that you are limiting maximal growth (in theory) to that part of the muscle.

Of course, what people don't realize is the long term effects of strength training: As we grow stronger, our muscles intrinsically grow slower. They literally express slower isoforms of myosin heavy chains, which contain the enzymes that actually 'burn' ATP.

This is simply because the slower a muscle moves, the higher its INTRINSIC force production. That has nothing to do with what happens in the outside world, and explaining that is a multi-hour endeavor best left to a seminar or a classroom.

So, in the end you are specifically making your fastest twitch groups slower and less fatiguable, which does specifically enhance high-end strength.

The fatigue, higher rep approach, enhances all fatiguable motor groups more or less equally. As one fatiguable motor group crosses the pH threshold that shuts down glycolysis, the next motor group kicks in and so on. This continues until there are (basically) no more motor groups left if you are tough enough to push that far.

If people have never trained low reps before, they will enjoy the strength gains because it is the first time they will see the true potential of the muscle they currently have.

Periodization is really nothing more than a fancy way to shift between building tissue and learning to use it.

Remember the key word: HYPERTROPHY. GROWTH. Intensity relative to 1RM matters for the CNS side of strength, not the tissue-level component.

There are some key take-homes, that bring us all the way back to long-standing recommendations I have been making: Do a single heavy set 1-2x per week, perhaps 2-3, but no more. Then work on lighter, higher volume training. At least one other time per week, work on lighter high volume training exclusively.

This allows your body to keep a high level of synchronicity, meaning in simple terms that your body is good at getting the most strength out of the tissue it has by activating it all simultaneously, while still allowing for good overall growth.

I haven't had one person fail to see very good results this way, and the truths in this thread are why.

I'm on my way out the door so will keep this post it self daily short. Various rep ranges have worked for various people, one thing to always look at it is what their over all volume or tonnage was for the session. Often it starts to come out near the same they just got there different ways. The heavier loads cause a much faster rate of protein degradation which requires a greater amount of recovery time. The lighter loads will stimulate less fibers and lower threshold fibers early on in the set which increases as fatigue sets in. There are some genetics to keep in mind where some people will naturally gravitate one direction or another and do well.

I'll check back when I have more time to get into this.

Low-rep technique is a bit of an acquired taste. Many people do not have the neural coordination to really get into it early on, or they try and push to hard to fast. I've run every trainee through it as the majority of all working sets I do are 5 reps or less for a various amount of sets. Certain movements are higher reps for tissue conditioning etc.

Maximum athletic effort can use much more than 60% but we're moving towards elite athletes in this category, years of training to condition and teach the body to not only use it but to un-block the inherent safeties that naturally limit us from self injury. You're looking around 90-92% for the elite of the elite who got everything just about right and have the genes to do it.

Ok now I really have to go, tried to briefly hit a bit of everything hinted at in here.

Joshua Naterman said:

Do a single heavy set 1-2x per week, perhaps 2-3, but no more. Then work on lighter, higher volume training. At least one other time per week, work on lighter high volume training exclusively.

Why not 4 weeks accumulation, 4 weeks intensification, or something like that? You think that daily undulating periodization is better?

You don't want to do a straight intensification until you are 4-6 weeks out from a competition. That is called peaking, and you will waste valuable developmental time doing so.

You can stay reasonably close to peak by simply doing some strength work 2-3x per week, but the volume needs to be fairly low so that you can still make good gains from your higher volume work. That is why I recommend only 1-2 sets twice per week. You could do 1 set twice per week and 2 sets once per week, but with straight arm work that can be risky unless you are smart about how long you try and hold the strength holds. With bent arm work this is less of an issue.

It is a matter of keeping the CNS used to being able to recruit a fairly large percentage of muscle fibers at the exact same time. To truly peak this has to be the main goal, but that's not a good idea to try and do all the time. All the best athletes and coaches will tell you the same thing: You can only attain a true peak 1-2x per year. I will be honest: I am not quite sure why those numbers are what they are, but I will tell you this: Peaking only once or twice per year gives you much more time to develop tissue so that when you peak the next time that peak is higher.

If you are not in competition, then there really is no reason to peak more than once a year if at all. Think of that as a yearly progress check.

Okay so if I dont need to peak, I can just do accumulation-intensification cycles in order to meet my goals, isn't that right?

When you start looking at peaking and competitive athletes we start to differentiate between a training peak and a competition peak. Even peaks for different competition if you want to add in Oly lifters working a 4 year cycles.

For an in training peak or test you're pushing the limits of what you can do without training on the nerve. You're not psyching yourself up for the effort. It's an honest test of where you're at without pushing to your absolute limit. It's an important difference and learning it will help as your training progresses.

If you enjoy the block training I personally would go to a 2week of each and not 4. 4 weeks of steady building up the intensity is quite a lot and while some people do benefit from it, you really should add a back off week after it and remember to also step back your figures when re-building as that max is higher then what you want to use to configure your training plan with.

Jumped in here late, trying not to overlap with what Josh is saying too much as this can be hard to digest for some people. Questions are awesome though.

One other thing. Keep in mind that depending where you're at in your training also has an impact. Not all of this might apply to you. Do not read something and immediately think you need to add it into your training. That is one of the biggest mistakes I see made, it's also why I chose to pick and choose a bit more where I put my two cents in.

Josh and Nic, thanks for your posts. Lots of good of information that is hard to easily come by otherwise.

Josh, you are right. I made a mistake when I said in my post that:

"The paper states that strength gains only occur if the last rep results in the orderly recruitment of (most or) all motor units that contribute to a specific activity;"

However, the rest of my post is more of a logical extrapolation of the following statement in the paper:

"The size principle states that when the central nervous system recruits motor units for a specific activity, it begins with the smaller, easily excited motor units and progresses to the larger, more difficult to excite motor units (2)."

I basically tried to see how low rep training to failure (reaching point of failure in a small number of steps using heavier weight) versus high rep training to failure (reaching point of failure in a larger number of steps using lighter weight) can be explained in the context of this size principle. On that score I don’t think I did too badly.

At least it elicited some good further insights from you Josh and Nic.

Nic, I am very happy to find confirmation of my notion that a true 1 RM effort (by orderly recruitment) is very difficult to do and better saved for those “special†occasions (like the Olympics). Having read so much about protocols, I am afflicted by what you might call protocol fatigue. So, I am also very happy to hear that a training protocol is individual and can combine a mix of what has been found to have worked, both by your peers (in my case, not athletes training for the Olympics) and by yourself.

My take away from this thread (I already posted it in my training log):

Nic Branson wrote on GymnasticBodies Forum, July 2 2012:

Various rep ranges have worked for various people, one thing to always look at is what their over all volume or tonnage was for the session. Often it starts to come out near the same; they just got there different ways. The heavier loads cause a much faster rate of protein degradation which requires a greater amount of recovery time. The lighter loads will stimulate less fibers and lower threshold fibers early on in the set which increases as fatigue sets in. There are some genetics to keep in mind where some people will naturally gravitate one direction or another and do well.

Low-rep technique is a bit of an acquired taste. Many people do not have the neural coordination to really get into it early on, or they try and push too hard too fast.

One other thing. Keep in mind that depending where you're at in your training also has an impact. Not all of this might apply to you. Do not read something and immediately think you need to add it into your training. That is one of the biggest mistakes I see made, it's also why I chose to pick and choose a bit more where I put my two cents in.

Nic when you do state your mind about such matters, people listen, that was an excellent couple of posts.

Thanks