T Nation

Hyperplasia

Hyperplasia…fact or fiction?

p.s. if you have to ask, your not qualified to answer.( not tryin’ to be a dick but…o.k. I am tryin’)

“you’re”
porter

just tryin’ to be a dick
porter

It seems that more exposure to chronic weight training is likely to lead to hyperplasia and to decent amounts of it.

But this really only occurs in reasonable amounts after chronic long term exposure to weights over years.

I’d say that for most people, the first few years of training improves neuromuscular coordination and hypertrophy. Once neuromuscular coordination and hypertrophy are significantly developed over years of heavy lifting, there can be hyperplasia due to fusion of satellite cell, which lend there nuclei to split muscle cells.

How about… To Be Determined?

Jason…do you have any recomended reading? According to several things I’ve read, Many “experts” consider this to be one of the big debates. One camp claims its not possible to create “the daughter cells” that the other camp claims is the primary action after muscle breakdown.

porter…I thought that was just a birth mark on your forehead, now I realize its a circumcision scar!

If you consider the activation of satellite cells to be hyperplasia, then yes, it can happen. Then again, these cells were there in the first place. They were just dormant.

I’ll see if I can come across the references - it’s pretty new stuff and I have only read recaps of these studies.

As for the fusion of satellite cells with muscle cells, why would you not consider this hyperplasia of the muscle cells?

There have been two proposed mechanisms to explain growth of skeletal muscle tissue as a response to loading:

  1. Hypertrophy: an increase in the size of individual muscle fibers;
  2. Hyperplasia: an increase in the number of muscle fibers.

This literature suggests that hyperplasia is possible in lab animals (i.e. Gonyea and pussy cats), but the literature is much less distinct in humans. Therefore, there is conflicting evidence. However, it is thought that even if hyperplasia occurs, it counts for only 5-10% of muscle size increases.

However, skeletal muscle hypertrophy has been observed time and again in both humans and lab animals.

What’s more intriguing is the issue that DCB brings forth: satellite cells.

This means of increasing muscle size would be classified as hypertrophy to me.

In response to heavy loading and muscle damage, the muscle cell releases IGF-1 (i.e. autocrine/paracrine IGF-1), which acts on the same muscle cell (i.e. myofibril) or adjacent myofibrils. The IGF-1 activates satellite cells and causes them to both proliferate and differentiate (this process can also be influenced by other growth factors, but few have the potential to cause both proliferation and differentiation).

After satellite cells proliferate, they are free to differentiate. These daughter cells can then assist the damaged myofibrils by binding themselves to the area that has been damaged. This will lead to an increase in the size of the fiber, not the number of fibers.

As of right now hyperplasia is fiction. It only occurs in animals. But in a few years who knows.

Let’s not forget about Myostat.

MPV999… sited work? Or is this just your opinion?

we are animals. Its not a question of being able to "make "it happen its a question of if it does take place.I think the problem is you would most likely need to tale a deep muscle tissue sample and then be able to duplicate the process again After LBM has been gained

Designing studies to investigate hyperplasia in humans presents some problems.

  1. You can’t kill a human subject and dissect them after your done with the study, as is the case with the animal studies that have shown hyperplasia after severe, long term loading.

  2. The primary method of counting muscle cells is via muscle biopsy. Biopsies are good, but it’s very difficult to make sure that the sample is taken from the same spot in the muscle, before and after the intervention. Not to mention the fact that they are invasive and painful. So until current methods are refined, or imaging advances to the degree that cells can be counted, it’s going to be very difficult to conclude that hyperplasia occurs after resistance training.

Gurux , although we are “animals” we have the advantage of opposable (hope Im spelling that right)thumbs, so we can lift weights. Animals do not, therefore nature developed a different strategy for animals to become stronger so they can hunt there prey. I am currently finishing my 1st year of excercise physiology so this is not just an opinion it’s based on science.

reguardless of a thumb or if its a two-toed sloth, you should know the basis of how muscle strength is gained by overloading and recovery.

Other primates have opposable thumbs. So what? To suggest that having them is some sort of requirement for “lifting weights” is ignorant at best. And to suggest that we’ve somehow “evolved” to lift weights is even worse. I doubt that caveman Bob was horribly worried about his bench.

What Gurux was saying is that it either happens or doesn’t happen in humans. Our understanding of that doesn’t change a thing.

I’m of the opinion that hyperplasia does indeed occur in humans, but it’s not our main source of gaining strength/size obviously as hypertrophy seems to be the main factor in that.

MPV - Congratulations on finishing your first year! What school are you attending? I think that Gurux’s point was that the fact that we don’t know something doesn’t make it “fiction.” The earth was round even when poeple thought it was flat.

DocT…I always like your answers. If I answered like you I’d get flamed and tagged an asshole…keep it up

In my opinion using the word opinion to decribe a scientific fact is IGNORANT. If we knew everything about how the body reacts to training the we would all be walking around with the body of a greek god. If you have something intelligent to say thats based on scientific fact,great, if not shut up and stop acting like some know it all jerk. The way it stands now there is no eveidence to support hyperplasia, and thats a fact!