T Nation

Muscle Growth - Hypertrophy vs. Hyperplasia

Howdy from texas fellow t-folk. where everything is bigger except for my pecs. i am not sure if i have a grasp on hypertrophy vs. hyperplasia and how it relates to ones ability to grow and was hoping for some enlightenment. how i understand it hyperplasia is the construction of brand spankin’ new muscle fibers. the type of muscle fibers you get while going through puberty regardless of whether you train or not. hypertrophy is nothing more than filling whatever existing muscle fibers you have and not the addition of new fibers. it was told to me that if you weight train while going through puberty this extra muscular load would allow your body to actually construct more muscle fibers than it otherwise would have. this might not make you big and buff at the time, but will lay the foundation for you to be able to achieve greater size later on in life because you will have more muscle fibers to hypertrophy. if you don’t weight train during puberty your body will only construct as many muscle fibers as you have been genetically predetermined. once puberty is over you have all the muscle fibers you are ever gonna have and all you can do to gain size is fill 'em up through hypertrophy. i would imagine you can only hypertrophy your muscles so much before they hit their limit. how do you know when you have hit that limit? is it possible that a kid who never lifted while going through puberty and has an average quantity of genetically derived muscle fibers can get the size of say…bill davey or jason arntz or the guy in the bowflex commercials? is my take on hyperplasia vs. hypertrophy even close to being right? any guidance would be great. thanks. kevo

Try the search engine first. This has been discussed several times in the past. If you still have questions after you look previous posts over, some of us will be glad to help.

steve - the search engine seems to be a bit uncooperative at times. i did several previous searches yielding a mixed bag of posts that did not speak directly to the point. i did sevral subsequent searches eventually hitting some interesting discussions that you were a part of. i will sift through them and see what i can learn. thanks, man. kevo

Kevo: Try the Testosterone Home Page Search engine also. Sometimes it will yield more.

By the way; while you’re searching. I have to give Texas and Alabama the nod for the prettiest women in the U.S.! (They’ve got California beat by a MILE!)Maybe Tennessee also if the Volunteer Women of the UofT are any indication!

I’ve been taught the hyperplasia vs. hypertrophy theory with regards to fat cells, but never been given any background in muscle cell/fibers. As far as your theory goes, it correlates to the fat cell theory almost exactly.

Mufasa, Whaddaya say?
Listen help me out with something. The search engine that is always mentioned here is something I don’t quite get. I was under the impression that the home page engine was the only one. Is there another?

In the blue field to the left of where you are reading right now, you will see “Subject” and “Author” with blank fields above them. Put a key work in one OR the other. Then, “click” one OR the other(“Subject” or “Author”). This is the search engine for the Forum. The Main Page Search engine seaches past issues of on-line “T-Mag”. You MUST click the word “Subject” or “Author” once a key word is put in. If you put in a keyword and hit “enter” (like on the Main Page), you will only get errors. Hope this helps.

The Main Page Search Engine gives you the option to either hit “Search” or “enter” once you’ve entered a key word or words…

in short, no one knows for sure if there is hyperplasia for muscle, but evidence strongly indicates that there may be. You have no control in trying to create hyperplasia v. hypertrophy. use the search engine or read the 1st chp of Supertraining.

Well I don’t know much on the subject but I do know that hypertrophy and hyperplasia both refer to the swelling of muscles. I was born with muscular hypertrophy (also called double-muscling), primarilly in my calves so I can speak from experience. Hypertrophy is when the muscles are tight as hell but really big. They are usually 1.5-3 times larger than what your normal muscle size would be at your height and weight and hypertrophy is also referred to as “double-muscling”) I don’t know if you want any form of hypertrophy or hyperplasia though because it might make tasks difficult for you. For instance, my calves are so large, I do toe-walking so I don’t constantly rip my back part of my calve. It looks funny when I walk or run. I also know that when I was going through puberty, I was never very active. Never played sports or anything else. I was the kinda guy that joined the chess club and student council so I don’t know if exercise is a predeterminer for permanent muscle growth since I have a relatively good build naturally. It’s either a myostatin “mutation” (I don’t know really how to define mutation since all humans have different varrying body types and genetics), congenital muscular hyperplasia (excessive androgen production that usually leads to precocious puberty (I think I had this as well)/very low cortisol levels), or wide/thick bone growth I think. I would suggest that if you want to have good permanent muscle growth, then theoretically (assuming you are going through puberty), you should get enough vitamins and minerals each day with a decent ammount of calcium, protein/carbs/and fats. I would also guess that eating large quantities of food and burning it off might prove effective as well in the long run. I know you can artificially induce muscular hypertrophy through intense exercise but I would suggest that if you are still going through puberty, not to obsess about getting too large. It is believed that having too big a muscle mass can screw up your growth plates (steroids ring a bell?). How this happens, I have no clue, but good exercise and diet will definately help. Hope this helps.

The number of muscle cells is determined at birth. Or largely so. As…dman(I believe it was dman)…says(okay I’m paraphasing) there is evidence for hyperplasia after birth(no real proof, however most muscle growth is due to hypertrophy. What is hypertrophy? The growth of a cell. Well in a nut shell. I think with muscle cells there is alot more going on(ie: growth of contractile protiens, more glycogen storage/substrate storage etc.) As for getting great results with weight lifting during puberty, this is just because of all the hormones that are in great abudance at this time. Joe I don’t think that steroids stop growth in teens because of extra muscle they develop but rather that testosterone in high enough dosages can close growth plates.

I must state that I’m not an expert. Also I wish someone who actually knew what they were talking about answered this tread. Ya I know it’s obvious I’m not an expert. :slight_smile:

nkeago, in Science and Practice among many others they say virtually no hyperplasia worth mentioning. However the slightly newer Supertraining lists lots of indirect evidence indicating muscular hyperplasia (gaining or splitting muscle cells, with the net effect of having more muscle cells).

Nice to see humble guys posting Nkeago (sp?).

If you look in the textbooks you will see that the general rule is that hyperplasia does not occur after birth in humans. Some of the literature argues that it may occur post- natally in humans, with the reasoning that larger animals require more muscle fibers, so hyperplasia will occur. To what extent? For how long? No one can say for sure. We should make a distinction here though. Hyperplasia is an increased number of muscle fibers. We most likely have transient hyperplasia in response to muscle traning though.

Mature muscle is riddled with baby muscles called satelite cells. These satellite cells probably contribute to increased muscle mass and in doing so, divide or multiply prior to fusing with existing mature muscle fibers. So, for a brief period you do have more muscle fibers before they fuse to old ones. This would fall into the category of hypertrophy though, as the end result is bigger fibers. This fusion of the satellite cell to the mature muscle fiber is necessary to maintain a constant nulear/cytoplasmic or DNA/protein ratio. So, because you are creating more protein (actually assimilating, but creating more myofibrillar protein) the cell needs to keep the DNA/protein ratio constant. A satellite cell is really just a nucleus (DNA) in a cellular shell, so by fusing with the mature fiber you increase the number of nuclei (DNA).

As far as adolescence goes, during adolescence various growth factors are elevated. Various growth factors facillitate the proliferation of satellite cells and their migration to the point of fusion with the mature fiber. Since there are higher concentrations of the various hormones and growth factors in an adosescent, the satellite cell will be more likely to divide and fuse, hence greater likelihood for hypertrophy (or at least the foundation of it). The alternative to the DNA/protein ratio argument set forth above might be that during adolescence you may coax the satellite cells to proliferate and fuse, setting the stage for increased myofibrillar protein synthesis later to maintain the ratio. This might be a more logical argument, but hypothetical none the less.

When talking to a traditionally educated Exercise Physiologist though, say hyperplasia does not occur in adult humans and you will get an A every time.

thanks to all who have contributed to this thread! this appears to be a very complex topic for which science is still trying to get a handle on. this brings me to another question regarding the muscle “girdle” or “sack” theory i read about which basically states that muscles are bundles of fibers enshrouded in a sack. the extreme stretching of this sack is required to give the fibers room to grow. the typical internal cellular pressures of the standard pump induced in a workout is not high enough to stretch this sack sufficiently, so one must actively stretch this sack while in a pumped state (i.e. for chest - following heavy pressing movements with flyes or pullovers). the idea is that the initial stretching of this sack is the real bitch, but once this muscle sack is stretched it is stretched for good. this allows a person who used to be big to quickly gain back his size with proper training and supplementation after a long layoff because the sack restriction is not present. hence, muscle memory. others have pointed out that the increased growth of adolescents is prolly due to their potent hormone soup, the increased likelihood of satellite cells being properly activated and the idea that the muscle sack is more impressionable during this time. this all adds up to the young weight trainer’s ability to gain mass quicker and easier with the ability to carry more mass later on in life. this is all just conjecture of course with no real data to back it up. any thoughts from those who possess more knowledge? kevo

I think there’s some good evidence for the muscle fascia (sack) theory. Trainees who lift regularly do get their muscle back pretty quickly after an extended layoff (compared to how long it took them to get it in the first place). Probably some neurological thing going on here too, since strength quickly returns too.

I seem to remember reading something about extremely high-tension movements (e.g. Olympic lifting) possibly causing hyperplasia... No, not a plug for Oly lifting, just mentioning that I read it somewhere. I can't remember where though... possibly Ironmag.

spanky - thanks for reminding me of the correct term “fascia”. i was beating my head against my desk trying to remember it!

an addition to my previous post is that those who do not weight train in their adolescence are not precluded from an increase in muscle mass later in life, just that once in adulthood it is more difficult to stretch the fascia (sack). kevo

that’s funny that you mention the t-vixens here in texas. i was an air force brat growing up, so i have been all over the states and i have to agree that texas is right up there with best of 'em. sure you will have your occassional road kill, but most of them are quite nice. :o) kevo

Thanks for the help. I figured out what the problem was. I log on under Netscape communicater and it has a very short screen. So I saw nothing below the yellow box with “post new message” and all that. The screen basically ended there. Took away all the tool bars, still nothing. Logged on with Internet Explore and bingo! Fucking computers. Thanks again. Peace.

dman thanks for clarriying that. Also where can I find more on this “supertraining”?

Steve great post I learned alot. Just one question? What was the (sp?)?? :slight_smile:

hyperplasia? I thought that went out with the whole flat earth thing. not being smart it just doesn’t happen, even IF it did it is obvious we can not control it. usualy people who claim its possible will site that swimmers for ex. have a larger # of fibers that are smaller in size but I think that just shows athletes are born not made, the same large # of fibers is NOT seen in swimmers that train the same but are not “world class”. and I think it was joe but hyperplasia and hypertrophy are NOT the same thing. peace