Myofibrillar vs. Sarcoplasmic Hypertrophy

Myofibrillar Hypertrophy is an increase in muscle fiber size due to an increased # of myofibrills which are the main componets responsible for contraction

Sarcoplasmic Hypertrophy is an increase in the the muscle fluid sarcoplasm as well as mitocondria and capilaries which contribute to more than half of the muscles size
Sarcoplasmic Hypertrophy is best stated as (I cant remember who said it) but “Bodybuilders are fancy sports cars with lawnmower engines”

Now my question is what weighs more? If 2 athletes are the same height and look to be the same build but one has been training with heavy resistance for low reps and is Myofibrillar and the other has been training the opposite and is Sarcoplasmic who should be heavier in terms of bodyweight?
Also I was under the assumption that after a certain point the need to be an increase size of a muscle is necessary in order to allow an increase in strength. Pretty much a bigger muscle has more potential for strength. Is this aside from the neural component of strength training that in speed/power sports where relative strength is important we strive for?

Sarcoplasmic Hypertrophy I believe would way more. I think if you compare a bodybuilder to a sprinter a bodybuilder will always way more at least in terms of male bodybuilders.

Reference Zatsiorsky’s Science and Practice of Strength Training for a discussion of this issue.

Funny you mentioned that because just before checking this thread I did.
Has a few paragraphs on it. I understand the concept completly but it doesnt answer my question.
Any other texbook you want to mention that you know off the top? I own many. I may take a look in a min.

SVS seems to cover it.

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Also reference Supertraining by Siff and Verkhoshansky

Any edition 4th or greater (these have an index)

There is some discussion on this subject.

Cool I actually quickly flipped through the index before but didnt find anything. I know it must be covered though. I will dig a little deeper later on. Thanx.
If anyone has anything to add that would be appreciated.

I believe he means density, Mass/Volume. myofibral hypertrophy is much denser. This is why sprinters have “hard” muscularity, while bodybuilders look soft in comparison.

See this is sort of what I am wondering.
So the myofibrilar content would weight more than the sarcoplasm?

Yeah because it’s denser.

Pavel Tsatsouline talks of this quite a bit. How the big muscle is useless. All show and no go. I like to have a bit of size but would rather pack a ton of strength into a leaner package that a bodybuilder type one with soft fluffy muscles.

centimeter cubed for centimeter cubed, no doubt… But sarcoplasmic hypertrophy is much easier to come by and has a higher potential for gains in size and weight.

bodybuilders are simply bigger, the comparison makes no sense to me

I would have expected sarcomeric hypertrophy to weigh more, but i have no evidence.
There is infact hardly any evidence on the sarcomeric vs sarcoplasmic hypertrophy thing…

Really? How on earth can you compare the density of a volume of sarcomere vs same volume of sarcoplasm by comparing athletes of VASTLY different sizes???

More on Myofibular and Sacroplasmic hypertrophy can be found online effortlessly.

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Yeah, but its all very theoretical theres not really any solid evidence at the moment.
Im sure that it does exist but it will be impossible to train for one and not the other. Just greater proportions of one than the other.

thats assuming that the bodybuilder has undergone more sarcoplasmic hypertrophy than myofibilar - also assuming they are the same size.

as for the original question…

both guys same build/size etc, my guiess would be the myo hypertrophy guy would weigh more… And im just basing this on observations of big bodybuilders who dont seem to weigh as much as they look like they will, vs a powerlifter or oly lifter who generally weigh more than they look like they will - and id base that on the higher density of contractile elements within the tissue - how youd go about working all this out is beyond me though

The neural enhancements will reach a point of diminishing returns. After a while (probably a long while) when neural improvements are very slow or have all but stopped you will need to increase muscular size. If one could improve the neural component of strength that would work too. So basically for a given “neural strength” muscular size must be increased to continue strength improvements.
Now if you can keep improving “neural strength” you ofcourse will be able to increase strength without aditional mass…
You can see this often in the gym…
Guys get stuck at a level of strength. For that type of strength training they need to get bigger to get stronger. Then they read something and train more for “neural strength” and gain a lot of strength but after a while their “neural strength” (for that type of training)is maxed out and they will need to gain mass to gain strength. Eventually guys will max out on their neural strength (regardless of the type of training cause they will be training optimally or close to it) and need to gain mass to get stronger.

*** ive been flippant with my wording but you get the picture

There is infact hardly any evidence on the sarcomeric vs sarcoplasmic hypertrophy thing…

Word. The sarcoplasm is simply the space surround the sarcomere. Mainly glycogen etc. Without the sarcomere you have no sarcoplasm. A cell can only store so much glycogen. It’s not like one can store 300 grams and another can store 2000 grams. One can’t independently increase sarcoplasmic hypertrophy to a great extent.

However, the confusion comes from looking at the training and muscle fiber adaptations in different athletes. People associate sarcoplasmic hypertrophy as muscle with little strength and sarcomeric as muscle with strenght.

When looking at the difference between the muscles of a bodybuilder and a powerlifter a bodybuilder will have larger muscles but they resemble an endurance athletes, with more mitochondria and slow twitch muscle fiber. These muscles are designed to accommodate to the task of training under conditions of tension combined with large amounts of fatigue. Even though it’s “real” muscle, gurus often refer to this type of muscle as “sarcoplasmic hypertrophy”

The powerlifter, on the other hand, has smaller muscles, less mitochondria and more fast twitch muscle fiber growth. These muscles are designed much more for max tension. Gurus will often refer to this type of muscle as “sarcomeric hypertrophy”

Now the real key is what better induces hypertrophy and how strength is measured. If tension alone were the key to getting large then every bodybuilder would just be doing heavy negatives for singles. Clearly this is not the case. FATIGUE with tension builds more muscle then tension alone. Period. Now how can you measure and compare the ability to put out fatigue with tension? Well take that same guru or powerlifter that is accusing the bodybuilder of being “all show and no go” and put him through the bodybuilders leg workout.

Instead of squatting 700 lbs one time lets go to the squat rack and do 405 for sets of 15 for 5 sets. Then move on to SLDL’s for 4-5 sets of 8-10. Then hack squats for 4 triple drop sets of 8-10 strip sets…same with leg curls. Finish off with sissy squats supersetted with leg extensions for 10-15 reps. Now who’s all show and no go in the task at hand? :slight_smile:

Also, the amount that once can grow from this type of training is under less genetic influence than the amount that one will grow from tension alone. In other words, guys with shit genetics will not grow as well from low volume powerlifting routines. They can grow but will tend to lean towards the higher set more fatiguing protocols.