Sarcoplasmic & Myofibrillar Hypertrophy question for Bryan

MaFi0s0

New Member
I understand, the heavier the weight = the more type II muscle fibers recruited therefore the more myo hypertrophy occurs, and the less sarcoplasmic hypertrophy occurs.
I also understand people generally regard the 8-12 rep range as being a balance between the 2 types of hypertrophy and the best for size.
And that progressively increasing volume rather than load increases strength although not as effectively and also with a ceiling effect on volume/sets.
From what I have gathered I assume Type II myo = accommodates strength, and sarco accommodates potential strength, and is the reason PLers use lower rep ranges but sometimes need to mix in higher rep ranges and train for some hypertrophy specifically.

With that said, I have been trying to find studies on rep ranges between 5-15 and hypertrophy effects, I could not find any to give me the information I was after. As they dont mention relevance between the 2 types of hypertrophy occuring and the potential ones dont include the credible 12-15 rep range but instead use the less effective 20-25 rep range.

What I did stumble across although unsure of is that bodybuilders appear to have a lot of Type I hypertrophy in comparison to PLers which I think is something people dont expect.
Something that is obvious is if you look at a PLer and a BBer who both have the same 1RM the BBer is A LOT bigger and I mean A LOT.
Having seen a beginner on strength programs like Starting Strength being able to bench 3/4 of their bodyweight for reps yet literally not even look like they have stepped into a gym and seeing the likes of 300lb Ronnie Coleman DB pressing only 4/3rds of his body weight as a work set, has me think sarcoplasmic hypertrophy accounts for a lot more of the size aspect than myofibrillar than what people believe.

Another thing of note, is when people say 65%-85% of 1RM being between 6-15 reps, how the hell do most people do 9 sets per bodypart at ~10 reps in a workout session and still remain above 65% 1RM. I am unclear on whether these studies refer to static 75% 1RM (straight sets of ~7-8reps) or the current moment's 75%1RM (Dropping the weight down each set to achieve a weight that would fail on the 10th rep).

With all the above taken into account it appears as though strength is not a big limiter of size, and that training in the 12-15 rep range close to failure at the expense of more progressive overload would give better results for pure hypertrophy than say sets of 8 reps and concentrating on stacking on more weight each cycle/workout. This would be assuming that most natural BBing trainees are too geared towards strength than size and have more of a PLer muscle structure.

Its hard to get anecdotal evidence of such because most people assume simply, more weight being lifted = more size being built. Also its a matter of fact that the more reps you are doing each set the smaller increments of weight you can increase by not because higher reps are worse for strength(not saying they are not btw) but a 5kg increase of 1x15 is a much bigger strength gain than a 5kg increase of 3x5.

I feel as though whenever this topic has been bought up on other forums it is written off as pedantic/over analyzing, but I feel it is very important as I believe it is what separates BBing and PLing, and its a lot more than just 2 rep ranges (1-5 and 8-12).

Due to no typical rep range inbetween concentrating only on either strength(neural adaptation), myo or sarco, as its been shown to all be shades of grey in terms of what each rep range specialises at, I dont buy into the tired response of "use every rep range that is the best", training in 5-15 should in a way stimulate the same % of strength, myo and sarco as sticking to the 8-12 rep range.

So the questions that are running through my mind are, does CSA(cross sectional area) in studies account for Sarco. hypertrophy, is progressive load really that important to size(as oppose to progressively increasing sets over a long period of time), and what is the real ideal rep range(or %1RM as they are 2 different things) for size(totally disregarding strength) if you had to choose 1. And please correct me with any misinformation or misinterpretations I may of written.
 
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Thanks. This is interesting:
Interestingly Bowtell (8) found that when the same total amount of ATP is turned over, exercise at 60, 75 and 90% of the one-repetition-maximum force results in exactly the same stimulation of muscle protein synthesis, suggesting that once all muscle fibers are recruited increases in tension above 65% cause no further stimulation in muscle protein synthesis. Even though I am not aware if the specific fractions were measured in the Bowtell study it would stand to reason that in light of the previous both fractions would be up regulated.
Completely contradicts (the study in the 2nd half of) http://thinkmuscle.com/forum/showthread.php?38981-5-5-week-SD-not-enough-(&p=212537#post212537
 
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Well I tracked down that study on google scholar and found a newer study citing it, it answered one of my own questions, seems anything higher than 9 reps is considered sub optimal when doing 3 sets.

http://jp.physoc.org/content/587/1/211.full

Thus, at an exercise intensity of 20% of 1 RM, the subjects completed 3 sets × 27 repetitions (reps); at 40%, 3 sets × 14 reps; at 60%, 3 sets × 9 reps; at 75%, 3 sets × 8 reps and those at 90%, 6 sets × 3 reps.

they show a sigmoidal dose–response relationship of myofibrillar protein synthesis to exercise intensity, with little increase from 20 to 40% 1 RM, then a bigger rise at 60% of 1 RM, with no significant further increase up to 90% 1 RM.
 
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There is also this article by Kelly Baggett
http://www.higher-faster-sports.com/nonfunctionalmyth.html

And if you really interested in real implications of different rep range(intensity) and other training parameters to hypertrophy you have to check this study
https://www.hh.se/download/18.38b5968b119e4d02f768000141/J-Wernbom-The-Influence-of-Frequency.pdf

more links
http://www.bodyrecomposition.com/muscle-gain/reps-per-set-for-optimal-growth.html
and this one
http://www.bodyrecomposition.com/training/periodization-for-bodybuilders-part-2.html
 
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Thanks for all the links, I skimmed through that big study and read all the rest. It appears there is a possibility that MPS duration after exercise could be affected by volume, although they wernt very clear on it as they were unsure.

And according to what I have read, 3x5reps@75%1RM (~4 reps short of failure on the last set) is going to recruit more Type II fibers than 2-3x15@50% 1RM with the last set being to concentric failure, there must be more to it than that?
I know this is what Bryan has been saying for so long now but I never thought of it like this, it changes how an ideal HST routine would be set up completely.
It points to the ideal HST routine being just 1 big very extended 3x5@60-80%1RM with a dropset of 15 reps each exercise in every workout. And that the 10s although seeming to be a good simple balance, wont have the %1RM load to sufficiently induce near as much myo hypertrophy despite effort or volume.
 
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And according to what I have read, 3x5reps@75%1RM (~4 reps short of failure on the last set) is going to recruit more Type II fibers than 2-3x15@50% 1RM with the last set being to concentric failure, there must be more to it than that?
To recruit type II fibers you need to
1)use heavy weight(>85% 1RM) you got ALL your fibers been recruited from first rep(as Lyle statement)
2)use less heavy weight but taking set to failure(near). According to size principle NS will recruit slow twich fibers at the begining of set. As they will drop(fatigued) during the set eventually NS will recruit fast twich fibers too.
3)use explosive(speed) training
4)occlusion(KAATSU) training, which is custom case of 2), just becuse of occlusion the II type will be recruited earlier

So I doubt if first case will recruit more II twich fibers, since the weight is lower then 85% and you don't perform the set to failure
 
Regarding number 2, in studies it showed higher rep sets to failure at a %1RM < 60% not creating anywhere near as much hypertrophy as 60-85% again bringing up my previous question of whether this was a %1RM variable from set to set(decreasing weight each set), or the static weight for the day/workout meaning straight sets nearing failure on the last. As I believe this changes randomly from study to study when they refere to %1RM and is not noted in the abstract or summary and would only be available in the full text.
Many people will assume %1RM means whatever rep you fail on, but volume changes those variables so they are not directly related. for example 3x5 to failure is a higher %1RM than 5x5 to failure.

Variable 75% 1RM would look like this:
1x9@75%1rm close to failure, peel off some plates
1x9 close to failure, peel off some plates
1x10, failure.

Straight sets with 75% 1RM would look like:
1x8, a little tough if not warmed up.
1x8, easy
1x8 failure.

or 1 set of 9-11 to failure, and this is why everyone thinks sets of 10 is golden when infact its using a %1RM lower than what is effective.

Also with 2x15 straight sets to failure your fast twitch muscle fibers are only being recruited towards the end of the set, whereas with 3x8 they are being recruited with more TUT and more load, which would probably explain the increase in myo hypertrophy, but does an increase in weight make up for a decrease in effort?
 
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Regarding number 2, in studies it showed higher rep sets to failure at a %1RM < 60% not creating anywhere near as much hypertrophy as 60-85% again bringing up my previous question of whether this was a %1RM variable from set to set(decreasing weight each set), or the static weight for the day/workout meaning straight sets nearing failure on the last.
I agree. Interesting that with occlusion we manage to get hypertrophy for intensities much lower then 60%
I guess that for intensity lower then 60% without occlusion we not recruit fast twich fibers, or tension stimulus is too low.

Also with 2x15 straight sets to failure your fast twitch muscle fibers are only being recruited towards the end of the set, whereas with 3x8 they are being recruited with more TUT and more load, which would probably explain the increase in myo hypertrophy, but does an increase in weight make up for a decrease in effort?
There is always a tradeoff between getting more tension(more weight) and low methabolick stimulus(we can't get enouth volume because we use heavy weights)
and getting more methabolick stimulus(short pause, high reps) but less tension
Of cause there is alway a possibility to incorporate both regimes in one workout(like 4x6-8 + 2-3x12-15), or separate them daily (Layne Norton split), or weekly (HST)

Now, which stimulus is more important?
I'm not sure.
It might also be different among individuals
 
My money is on 3x6-8 + 2x12-15 but which set to take to failure?
Do you take the last heavier set to failure because weight does not make up for a decrease in effort(common perception and the basis for "any rep range will work train hard add weight"), or do you take the lighter sets to failure because the true goal for the higher reps is to actually fatigue the muscle. The consensus on this forum is to not do dropsets to failure.
But the answer lies in the full text of ALL these studies and I think there must be hundreds of them, pointing to 60-85% 1RM with a peak at 75% showing the most myo hypertrophy, but then carelessly summariesing it as a rep range of 6-12 or 8-10 without any regard to volume therefore making the conclusion erroneous.
 
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Personally, I never go to "true" failure.
Always leave at least 1-2 reps in the tank.
In the RPE scale it's 8-9
This way you will be able to train more frequent and perform more volume in workout
I think you will loose more than win from going to failure in each set and I think that it's heavy "enouth" to stop 1-2 reps short of it
 
http://www.ampedtraining.com/articles/building-muscle-mass-muscular-growth
In practice, the actual rep range you use doesn’t seem to matter that much. You can do triples or you can do sets of 10 as long as the weight is ‘heavy enough’ and as long as you’re racking up enough total volume. By ‘heavy enough’, I mean sufficient to stimulate gains. For most people, the cut-off is going to be about 65-70% of your one-rep maximum. For those exercises that you can’t or shouldn’t test 1RM weights, figure that if you can do more than about 12 reps, then it’s too light.

http://www.ampedtraining.com/exercise-science/rep-speed-fatigue-motor-units
Look at it this way. A very heavy set, say your best set of 3-5, is going to recruit all available MUs right off the bat (at least, all the ones you can voluntarily recruit) because the weight is heavy. If you didn’t do that, the bar wouldn’t move. Those MUs have to be activated in order to create enough force to lift the weight. A lighter set of say 8-10 reps, that’s a different story. You’re only going to recruit a smaller sub-section of the total available MUs, because of the size principle – the smaller MUs are all that’s required to lift the weight. The thing is, during a longer set, more of those MUs are going to be fatigued, which is where the idea breaks down.

That’s the difference. A set with a very heavy weight is going to recruit a lot of MUs; a longer set with a moderate weight is going to fatigue a lot of MUs. It’s a subtle distinction, but very important – if you’re saying that a set should get easier if you recruit more MUs, you can’t just ignore the role of fatigue. A fatiguing set may not recruit more MUs simultaneously (as is the case with a very heavy weight) but it most certainly can fatigue more MUs over the course of a set.
 
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