Building muscle - why do they grow bigger?

I’ve been working out every other day for about a month now, and I’m beginning to see the start of what could be signs of the opening sequences of muscle growth. Why do muscles grow back bigger when they repair, as opposed to the way that they were before? Why do they “overheal”?

When you work out, what you’re really doing is tearing your muscles. Little holes in the muscle form, and, after awhile, scar tissue heals over them, making them stronger than it was before.

With all due respect, Hippy (whatever level that is :slight_smile: ), I’d like to see a site on that before taking it at face value. Especially the part about scar tissue.

I of course meant “cite”, but a link to a site would be great.

Here’s is a good amount of info on how muscles work…
and to take a quote from the 3rd web page

“Strength training increases the myofilaments in muscle cells and therefore the number of crossbridge attachments which can form. Training does not increase the number of muscle cells in any real way. (Sometimes a cell will tear and split resulting in two cells when healed). Lactic acid removal by the cardiovascular system improves with training which increases the anaerobic capacity. Even so, the glycolysis-lactic acid system can produce ATP for active muscle cells for only about a minute and a half.”

oh, Jim Swan is the undergrad A&P instructor at the University of New Mexico

Ah! Now I know why I never took biology (thank heavens for Sound and Acoustics, Electricity, and Physics!)…

The information on those pages is not in English. Is it trying to say that the muscles get torn apart when working out, and when they heal, they grow “fingers”, making the muscle into a ball of yarn??

I think people here are attempting to address a few different questions. Most people are addressing the how not the why. First off, strictly speaking, or even loosely speaking for that matter, it is not scar tissue that forms, its closer to what the third dude said.

Now the why.

Lamarck may have been wrong about his use/disuse theory for evolution, but he could have been right if he substituted “Giraffe’s Neck” for “Muscles.” Obscurtity aside, your muscles grow because the recent workload “tells” your body to ready it self as if this new workload will be the norm. Of course I’m personifying it, but the fact is, when the muscle fibers are torn from the exertion the body throws in a few extra fibers in case the guy does the same thing tommorow. It is simply an organism adapting to it’s environment on the fly - the whole purpose for gene machines in the first place. The human body has millions of ways in which it seems intelligent (a million jokes there) - For instance, if you starve yourself for a period of time your body will stop burning protein for energy and go full time on fat. The evolutionary “reason” for this is if you go hungry, hunting for food probably isnt going so well. Therefore I better take his emergency supplies rather than eat the very muscle that helps him hunt for food in the first place. Does any of this make any sense at all anywhere?

I think that answers the question. What’s the problem? You can get stronger without getting bigger muscles due to the increase in myofilaments and (not mentioned) increased neuronal response. But the glycolysis-lactic acid system can produce ATP for only about a minute and half, is only a half-truth.

ATP is the source of the energy in all work. The chemical energy released by the breaking of a bond is converted into mechanical energy. ATP is thus reduced to ADP. (Adenine triphosphate to adenine diphosphate.) It has to be reconstituted, and there are three ways the body can do this.

(1) The creatine phosphylation. This only lasts for a few seconds (10-15 seconds). This is why creatine is a good supplement for work that requires quick bursts of energy.

(2) The anerobic system, described above as the glycolyis-lactic acid system.

(3) The aerobic system. The only limit to this system is the substrate (glucose - and fat and protein can be converted into glucose). This is the system used for endurance events, but also for any exercise of any duration over 1 1/2 minutes. Oxygen is needed for this, and as the name applies, oxygen is not necessary for the anerobic system.

I dont know if a minute and a half is the exact measurement of the time required, but the waste products of the anerobic metabolism is what limits the duration of its use. At that point the aerobic metabolism must take over to continue the production of ATP

I have to agree with Hippy on this, muscles get to a certain size & the rest is scar tissue. Why it looks so nice & well defined is a mystery.

So, handy, would you like to give any proof of your statement? I’ve managed to show otherwise and would love to see why you believe scar tissue is whats there.

If working out on weights created scar tissue, I don’t think anyone would be working out. Scar tissue, of course, has very little value to the body. It’s just an emergency tissue the body creates after an injury. People talk about “breaking down” muscles and building them back up stronger. They say you have to work out to exhaustion in order to break them down. That’s all BS.

The body adapts to stress by getting stronger, not weaker, which is what scar tissue is. If the body is unable to adapt, it will break down – the body. The ability to adapt was called “eustress” by Hans Selwe (sp?), and this kind of stress is good for the body.

I didn’t say I disagree with you kinoons, I simply agree with Hippy. Probably cause we once read the same newspaper article on it or something.

Handy, how on earth do you expect me to believe that you agree with both Hippy and myself when we give two totally different answers to the question?

With all due respect kinoons, I did not say I agree with you, I said I agree with Hippy. There is however, often more than one answer to a question. Besides, I have to research your answer first. I kinda liked the one Hippy said about the scar tissue cause I read something like that a long time ago.

Anything any one reads “a long long time ago” concerning exercise physiology you can just throw in the bin. A long, long time ago conventional wisdom said don’t drink water while exercising, too. Then they said drink only water as glucose will slow the absorption of water. Now we know that an 8% solution will not slow absorption, and some salt will actually increase the rate of absorption.

Exercise physiology has learned much in recent years, and there’s still plenty to learn in this field. It’s really a new science. I once ran a marathon, about 22 years ago, where all they supplied was water, because that’s what was thought to be correct then.

So, you high school kids out there, if you don’t know what to study in college, this is a good and growing field.