Talk:Muscle (muscle)/Archive 1

Archive 1

Muscle Strength

I'm confused from this statement in the article, "Contrary to popular belief, the number of muscle fibres cannot be increased through exercise; instead the muscle cells simply get bigger. Muscle fibres have a limited capacity for growth through hypertrophy and some believe they split through hyperplasia if subject to increased demand." They just stated that muscle fibres canot be increased through excercise, however they then mention that that can be split by hperplasia?

Hqduong (talk) 06:24, 13 April 2008 (UTC)

Pennate muscles? MAJOR OMISSION

Why is pennation and its functional consequences missing from the gross anatomy section? This is a major and important aspect of muscle mechanics. I'll add in something quick at the moment, but I'm currently quite busy and felt this should be tagged as a *major* omission (on par with leaving out fiber types) which needs extensive editing. -- Mokele 12:18, 1 November 2008

Isn't pennation more appropriate for the skeletal muscle section - as would be fiber types? QuietJohn (talk) 16:18, 25 May 2010 (UTC)

Mammal-Centric Article and other gripes

This article is currently mammal-centric. Also, Cardiac muscle is usually defined as its own type rather than simply an instance of smooth muscle. I do not feel I have the expertise to expand the article though so I am going to do that annoying thing of just complaining on the talk page instead of just fixing it myself. --Qaz

Response: Sorry but what you wrote is not correct. Cardiac muscle is not an instance of smooth muscle. Cardiac muscle is distinct from smooth muscle. There are three recognized types of muscle: Smooth, Skeletal, Cardiac.--Gacggt 00:30, 30 May 2006 (UTC)

There are industrial and research projects for artificially augmenting muscle. Is the Wikipedia an appropriate venue for this topic, since it is a future entry?

I agree with Qaz. This article is entirely about the human body. The title is misleading.--76.81.180.3 21:16, 31 October 2007 (UTC)

Said comment is more than a year old. Sadly wikipedia is limited by the knowledge of its contributors, and I lack specialization in reptile muscle biochemistry. WLU 23:43, 31 October 2007 (UTC)

Types of Energy Production?

Would a knowledgeable biochemist explain the 4 methods of energy production in muscle tissue? I recall that 2 are aerobic, and 2 anerobic, but i forget the actual reactions and hormones involved. --AnthonyQBachler

Yeah there is an error the muscle page, it says that "the glucose molecule can be metabolized anaerobically in a process called glycolysis which produces two ATP and two lactic acid molecules" this is not only flase but also incorrect. While it is true that the cell can use glycolisis so can every other cell in the world. Glycolisis is a universal metabolic pathway. Also glycolisis does not end with latic acid molocules. It ends with pyurvate, then through latic acid fermentation we achieve the lactic acid. Glossing over this point not only gives falsity to glycolisis but also does not inform the reader exactly how the erergy needed is created. —Preceding unsigned comment added by Rizzss (talk • contribs) 03:59, 7 January 2009 (UTC)

DOMS & lactic acid

according to http://www.naturalphysiques.com/cms/index.php?itemid=142, DOMS is not caused by lactic acid buildup, as stated in this article

This is true. I will correct. Dan100 19:22, Feb 20, 2005 (UTC)

It is no longer believed that the cause is small tears in muscle fibre. A more recent study (by Ji-Guo Yu at the Swedish University in Umeå) has disproved this old theory, showing that there are no tears in the muscle.

Yes I agree with the stated above. The theory from yu gi guo failed to find tears in the fibers immediately after the exercise and thus has re-interpreted data long thought to be linked with sarcomeric damage as protein synthesis and creation of new sarcomeres (sarcomerogênesis) thus being much more a process of adaptation rather than a process of celular repair. The reference for it can be found here:

Yu, J., Carlsson, L. & Thornell, L.E. (2004). Evidence for myofibril remodeling as opposed to myofibril damage in human muscles with DOMS: an ultrastructural and immunoelectron microscopic study. Histochemistry and Cell Biology, 121(3), p. 219-227.

Hyperplasia

There was a paragraph that suggested that muscle hyperplasia could occur in humans. This is untrue - it has only been observed in animals - so I removed it. Dan100 19:22, Feb 20, 2005 (UTC)

Human specialization would nott be a reasonable excuse to delete something in a general article on muscle. It would, however be more appropriate to put it in the skeletal (and cardiac?) muscle sections. Wikipedia's article on hyperplasia seems to be a little less certain about its occurrence in humans. —Preceding unsigned comment added by QuietJohn (talk • contribs) 16:30, 25 May 2010 (UTC)

human muscle action?

A larger wiki forum on this area may be found on sense-think-act.org which may be of interest to contributors to this area...

Hmmm. Nice, but it's a bit secondhand information. JFW | T@lk 13:53, 6 Mar 2005 (UTC)

GFDL statement for "strongest muscle" section

This statement is made for GFDL purposes to allow deletion of Strongest muscle in human body. The section Muscle#Which is the strongest muscle in the human body? was inserted by a 08:39, 3 Apr 2005 edit by User:Dpbsmith. This edit consists of material developed almost entirely by User:Dpbsmith on 30-Mar-2005 and 31-Mar-2005, with two typo/punctuation corrections by User:Mindspillage.

I would never vote for deletion in wikipedia. Instead, every time that is possible, just re-organizing, move to another area / section, or even folder it up, like adding it to muscle/strongest muscle with a link from the main article.

Personally, as I've read most of the article, that section does provide good information about muscles, and by analysing such thing (as what's the strongest and /or weakest muscle) one can have a good start if willing to go deeper into research for more specific information.

--Cacumer 11:50, 24 December 2005 (UTC)

3rd Party Suggestion:

In regards, It was through a link in the tongue article that I came to the strongest muscle section of the article.

It is suggestable that said claim of the tongue being the strongest muscle in the body is a referanace to the overall power or strength of "spoken word" for which word "tongue" behaves as a synonym. Not in the context of any physical work or output of force.

If this section is maintaned here or in another article I suggest this be included.—Preceding unsigned comment added by 75.70.236.249 (talk • contribs)

Dude, that's from 2005. I think the article very clearly describes physical muscles, and your comment is original research. WLU 16:43, 20 July 2007 (UTC)

Strongest muscle

Help on this section would be greatly appreciated. This was a rescue attempt on a substub article that asserted that the tongue was the strongest muscle, without any attribution. VfD consensus was that it belongs here rather than in a separate article. Dpbsmith (talk) 13:47, 3 Apr 2005 (UTC)

This section is now soo large it puts the article out of balance. I am also concerned about original research. Could you please trim this down to something smaller? JFW | T@lk 06:16, 4 Apr 2005 (UTC)

My big problem in trying to assemble this was the occurrence of many throwaway remarks about thus-and-such muscle being strongest without any reference of clear explanation. The article started with a single line asserting that the tongue was the strongest. In every case, it is NPOV-true for each candidate muscle that there are many, many, many assertions that it is the "strongest." But, yeah, in many cases I'm putting my guesses as to the rationale as a sort of placeholder. Although this is silly trivia-question stuff, I think it should be treated somewhere in Wikipedia, and the consensus was that this article was the appropriate place for it. I'll do my best to trim, but what I really need is help. Dpbsmith (talk) 14:14, 4 Apr 2005 (UTC)

Well, I've at least managed to condense the table of contents and removes the over-conspicuous headings and the whitespace associated with them. The tone of this section is different from the rest of the article and the quality of the information is lower. I'm retitling the section "Trivia: the strongest human muscle" to separate it conceptually.

Please, please, have you got any guess as to the origin or explanation of idea of the tongue being strongest? Does this make any conceivable sense to you? Typical sighting: "The tongue is the strongest muscle in the body and teeth move with pressure" [1] [Dead link replaced by Internet Archive link. -- ToE 14:14, 25 February 2016 (UTC)] and that's from a dental group... Dpbsmith (talk) 14:44, 4 Apr 2005 (UTC)

I've only looked breifly at this article, but I have an idea that may help. First off, musclular strength is more complicated than simple cross-sectional area as the layman would understand the term, and is more accurately measured with the measurement of physiologic cross-sectional area, which takes into account the alignment of muscle fibers within the muscle (whether they are fusiform or pennate muscles). Perhaps a new section called "Muscle Fiber Alignment" could discuss these issues, and within this section, side facts like the speed and strengths of certain muscles could easily be worked in as their respective muscle types are explained.--Bennihana 21:56, 16 Jun 2005 (UTC)

It's a lot more than that. It's also a function of the number of fibers recruited (by the nervous system), the rate at which they twich, and the compressibility of the fibers. →Raul654 00:11, Jun 17, 2005 (UTC)

Perhaps it would be best to just trim this section as much as possible, leave it at the end of the article, and add sections for alignment and compressibility, then talk about recruitment (and its relationship to force and speed) under "Nervous Control" (definitely ought to be there anyway) and also talk about twitch speed under the "types" explanation?--Bennihana 06:34, 17 Jun 2005 (UTC)

What about the weasel words used throughout this section? It states: ' and are sometimes claimed to be "100 times stronger than they need to be." '. This doesn't seem fully encyclopedic to me. The whole section looks like it needs to be rephrased and referenced. —Preceding unsigned comment added by Boblive (talk • contribs) 00:43, 17 March 2010 (UTC)

Draft revisions to article

Following proposed work-in-progress revision:

Striated and Smooth Muscle

Muscle that we use in physical exertion, be it lifting a box or batting an eyelash, is striated muscle. However, muscle that is used to move food through the intestines and modulate blood flow through tissues is of a different type, smooth muscle. The two types are named after their microscopic appearance, where striated muscle shows cross-bridged filaments running along the length of the cells and smooth muscle does not. This filament structure is the contractile apparatus that transforms energy release from the hydrolysis of ATP into longitudinal tension against the cytoskeleton of the muscle cell; the complex structure of muscle at the tissue level is so designed that the contraction of individual muscle cells combine to result in an organ-level shortening of the muscle as a whole.

(Courtland 17:14, 2005 Apr 6 (UTC))

The first half is a bit dumbed down. I would avoid the use of "we". It may be enough to state that striated muscles are used voluntarily, while smooth muscle is under control of the autonomic nervous system and cannot be conciously controlled. JFW | T@lk 17:22, 6 Apr 2005 (UTC)

beginning parts of articles are meant for the general public and to start pumping in with "sarcomere" doesn't help the general reader; keep in mind also that this is going to be a point to which much of the reading public would go for information on Muscle -- as that's the title of the article. It might be dumbed down to you, but I assure you it's at a reading level and sufficiently demonstrative to be apprehended by the majority of the reading public. yes, need to change, perhaps, the familiarity of "we". Courtland 17:26, 2005 Apr 6 (UTC)

on voluntary/involuntary: that's not the distinction between smooth and striated muscle; it happens that there is a correlation but it's not perfect and we do have indirect conscious control over some supposedly "involuntary" muscle functions. I don't want to expound on that in this article because it can be kind of controversial and the general public looks at that stuff and thinks "pseudoscience" or "Ripley's Believe It Or Not". Courtland 17:30, 2005 Apr 6 (UTC)

If I may add my two cents, as I'm not a specialist in any biological area, just a regular curious, I would change almost nothing in your text, Courtland. But yet, since this is a request to review, I would do the following:

Muscles that are used to move food through the intestines and modulate blood flow through tissues can be called smooth muscles. While muscles used in physical exertion, be it lifting a box or batting an eyelash, are of a different type and can be called striated muscles.

The two types are named after their microscopic appearance, where striated muscle shows cross-bridged filaments running along the length of the cells and smooth muscle does not. This filament structure is the contractile apparatus that transforms energy release from the hydrolysis of ATP into longitudinal tension against the cytoskeleton of the muscle cell; the complex structure of muscle at the tissue level is so designed that the contraction of individual muscle cells combine to result in an organ-level shortening of the muscle as a whole.

Also I would change the title for whichever is the name for that classification (the two types) and if those names are "oficial" names I would change both "can be called" to simply "are". Also, I like the plural better since I'm starting to believe as I read the article that most muscles don't work alone.

--Cacumer 12:08, 24 December 2005 (UTC)

Which is the most active muscle in humans?

I need to know this answer since i saw a game show programme (local variant of Who Wants to Be a Millionaire? ) where the same question was asked i.e. Which is the most active muscle in human body? The correct answer was given as the eye muscles, but I thought that the heart muscles were the most active since they don't take rest even at night. How is "active" measured? And how can the eye be active when it is asleep at night? this is perplexing... any docs here or anyone else qualified can settle this issue. Tx. Idleguy 16:58, August 27, 2005 (UTC)

In terms of number of twiches per second? They eye has it by a mile. The heart beats 60-100 times per minute, or about once per second; the muscles that control the eye are capable of rotating it several times in the span of one second. Just think about it this way - roll your eyes around in a circle quickly, and then thick about how many times your eye muscles had to move in order for that to happen. →Raul654 17:34, August 27, 2005 (UTC)

• Rolling your eyes around isn't the greatest analogy, because there are so many muscles in the eyes involved in that movement (lateral, medial, inferior, and superior recti, superior and inferior obliques, etc.) Semiconscious (talk · home) 18:26, 27 August 2005 (UTC)

• The eyes aren't at rest at night, either. REM (rapid eye movements) are a notable feature of the dream-state. Regardless, this is a silly question. "Active" could be measured by average number of contractions per minute, total contractions during the day, amplitude or frequency of EMG (electromyogram), etc. The heart is a large, powerful organ so would give a larger EMG (EKG) response, but there are many "eye muscles" to control various aspects of eye movements. Anyway, does that at least in part answer your question? Semiconscious (talk · home) 18:26, 27 August 2005 (UTC)

Yes. Thank You. I think they should have avoided such questions where measurements for "active" are as different as you said. Idleguy 11:38, August 30, 2005 (UTC)

I believe we are missing "muscle" definition as being either a "group of muscle of a certain organ" or just a single muscle as first defined. That also goes for the problem found by classifying the tongue as the strongest "muscle", as it's not compound of just one muscle, so is not the eye, or (probably) any other organ.

I would guess that, in general aspects, when we say "muscle" we mean the whole group as most people won't know how to tell how many muscles are around a specific organ. That would explain and agree with that eye answer, and maybe with the tongue affirmation as well.

--Cacumer 11:57, 24 December 2005 (UTC)

Also while you are asleep you have the sleep fase REM or Rapid Eye Movement where your eyes move very rapidly while dreaming. Also think about this. Every single time you move your eye muscles move to compensate for the movement of the head so your eyes can remain focussed on the same object. With out your eye muscles moving so much images would be very jerky. —Preceding unsigned comment added by 69.181.212.145 (talk) 01:58, 24 May 2010 (UTC)

Muscle evolution

Thanks goes to Nunh-huh for the source. Feel free to expand this section, as it still needs a lot of work.

See more info here at this wiki reference desk article: [2]

Link seems to have been removed. This seems to be quite an informative review Katja Seipel and Volker Schmid. Evolution of striated muscle: Jellyfish and the origin of triploblasty. Developmental Biology Volume 282, Issue 1, 1 June 2005, Pages 14-26QuietJohn (talk) 06:57, 24 May 2010 (UTC)

Muscle#Efficiency

I'm sorry if this is too irrelevant. I'm just wondering if there is, or where we can find, more information about muscle efficiency. This looks like it must be a whole area of study about it, and it looks like it would have a different name, and that's the reason why I'm asking in here instead of just go google for it (as I haven't even tried it yet).

Also, if I'm correct in guessing that, it would be interesting to increase that article topic and add comparison information about muscle efficiency, both within human body, animals and maybe other living beens (as this is actually what I'm looking for, right now).

Thanks for understanding.

--Cacumer 12:12, 24 December 2005 (UTC)

Neuromuscular disease

I've pared down the Disease section, and used the information there to start an article at Neuromuscular disease, which could really be expanded much further. Proto||type 12:32, 28 March 2006 (UTC)

Muscle atrophy and Muscle hypertrophy

I added a new page called "Muscle atrophy"; should this also be included on this page? or on the skeletal muscle page? It seems that the signaling which causes skeletal muscle adaptation (atrophy & hypertrophy) is relevant, but perhaps not on the general "muscle" page... thoughts? Gacggt 00:30, 30 May 2006 (UTC)

Mandibles

Someone inserted this comment into the article (which should be here on the talk page):

there are muscles called mandibles but i don't kow where they are so i need help.. but i am just typing this here for no reason

Pentawing^Talk 03:16, 1 June 2006 (UTC)

I think that this was benign vandalism and I think that it should have been complelely deleted from the wiki. Mandibles are jaw bones. Snowman 08:31, 2 June 2006 (UTC)

Please expand

Can some one please expand the following: "Exercise has several effects upon muscles." What effects and how it works? How does muscles become bigger, after you excersice ? Igoruha 10:34, 26 July 2006 (UTC)

I would like someone to expand the article on the subject of temperature effect on muscles specially extreme cold / warm temperatures --YoavD 04:57, 11 January 2007 (UTC)

Nervous Control section

The "Nervous Control" section doesn't even mention what a motor unit is. It lacks context, as it is. Fuzzform 22:51, 21 October 2006 (UTC)

Proposed reorganization

Previous commentators on this page have commented that it is mammal-centric. Indeed, it appears to focus almost exclusively on human muscles. The encyclopedia does need coverage of non-human musculatory systems. We also already have muscular system. Perhaps it would be a good idea to move human-specific content there, leaving a summary here and expanding animal coverage here. -- Beland 14:39, 4 November 2006 (UTC)

Merge of Muscular system

There's a merge tag with a proposition to move the content of muscle over to muscular system.

Merge backwards: I think the content of muscular system should be merged into this article, then a re-direct put it. This seems like a far more comprehensive article and "muscular system" is a pretty obscure title for what is really about muscles. WLU 13:42, 27 November 2006 (UTC)

Do Not Merge: Muscle and Muscle SYSTEM are two different things. —The preceding unsigned comment was added by 213.216.199.26 (talk) 10:30, 5 December 2006 (UTC).

Sprotected

I've sprotected this page. There is daily mindless vandalism, including 29 edits today that constitute nothing but vandalism and its reversions. JFW | T@lk 16:23, 16 April 2007 (UTC)

whow physiotherapist treat bruise?

female picture

discussion request. do you think a female bodybuilder picture should also be included later below the existing two images. the two there already perfect, but perhaps women should get equal representation or this crazy thinking because that's the only reason. Nastajus 06:06, 1 June 2007 (UTC)

Sure, Find a good one and put it up.Wikidudeman ^(talk) 06:57, 1 June 2007 (UTC)

No, stop being so overly-PC66.74.172.147 22:00, 26 June 2007 (UTC)

Excuse me? "Overly-PC"? Because I think a picture of a female could do well in this article I am "Politically correct"? Wikidudeman ^(talk) 22:02, 26 June 2007 (UTC)

Based on past contribution, a troll, not worth talking to and kinda tempted to just erase it. WLU 23:26, 26 June 2007 (UTC)

Picture

I dont think the body builder picture is not a nesseesary visual aid.—The preceding unsigned comment was added by Epg (talk • contribs).

The image clearly details the various muscles of the human body shown on an actual human body in this case a bodybuilder who has developed them. The image aids in the understanding of the article and is therefore necessary. Please clarify your objections. P.S. Be sure to sign all of your posts after you make them otherwise people can't respond.Wikidudeman ^(talk) 01:49, 4 June 2007 (UTC)

Embryonic origin in error

Not all skeletal muscle or smooth muscle is mesodermal in origin:the smooth muscle of the great arteries and various facial skeletal muscle are of neural crest origin. —Preceding unsigned comment added by 74.171.83.219 (talk • contribs)

Muscle is not fat but an organism that enables you to move around without it you wouldnt be able to lift or apply pressure to anything —Preceding unsigned comment added by Jako Spacko (talk • contribs)

First comment - feel free to update the page. Second - I don't understand what your comment refers to. Could you clarify? WLU 13:04, 10 June 2007 (UTC)

Aren't Type IIx and Type IIb The Same Thing?

I read in a book that Type IIx is another name for Type IIb. The paper cited for the wiki article in not viewable so can a third party please confirm whether or not the muscle types are different? Thank you!24.83.178.11 07:40, 15 June 2007 (UTC)BeeCier

Type IIx and Type IIb have different MHC (myosin heavy chain) isoforms. Here is a paper for reference "Myosin Heavy Chain Composition in Human Masticatory Muscles by Immunohistochemistry and Gel Electrophoresis" Korfage et. al. Journal of Histochemistry and Cytochemistry, Vol. 51, 113-119, January 2003. There are other papers, but I couldn't find a good review paper on fiber typing. Also, I remember my mentor telling me that IIb muscle is predominantly found in mice (not sure about other organisms). In human skeletal muscle, the fiber types are predominantly Type I, Type IIa, and IIx, with fiber type shifting visible between IIa and IIx in response to various stimuli.Cecalder 21:55, 9 August 2007 (UTC)

I started to respond to this, but then saw it may be useful for the motor unit page so I moved it to the motor unit discussion page. I'll try to figure out the layout and maybe add it to that page. QuietJohn (talk) 18:18, 25 May 2010 (UTC)

Muscle Contraction and Vasoconstriction [?]

---I have a question about how exactly blood vessels inside muscle tissue act in relation to muscle activity.

When (either voluntary, smooth, or cardiac) muscles contract, does it cause blood vessels inside them to constrict, or to dilate, or does it have any effect at all?

I'm curious as to how thermoregulation and human activity relate. I'm not a medical professional, but I imagine that involuntary muscle movements (e.g. shivering) would cause vasodilation, since the body is trying to raise its temperature ---although they could actually be causing vasoconstriction in the extremities, since the body is programmed to preserve its brain and vital organs, at all costs.

When (for example) an individual flexes his bicep, does more blood flow to said bicep, or less? When his stomach digests food, does more blood flow there, or less?

--Please let me know, because I'm REALLY in the dark here. Pine 20:08, 21 September 2007 (UTC)

Wikipedia is not a textbook, though you might try the reference desk. The skeletal-muscle pump drives blood to the heart, but that's veins, not arteries. Exercise does increase blood flow through muscles due to an increased metabolic activty within the muscles that prompts dialation of the arteries feeding the muscles. Digestion diverts blood towards the gut, though exercise, adrenaline and general SNS activity diverts it away. WLU 15:49, 24 September 2007 (UTC)

Intramuscular pressure increases during a muscle contraction. Pressures depend on level of activity, but have been measured to be in the range of 5 - 50 kPa. Blood pressure (~15 kPa) is reduced to ~5 kPa in capillaries, so it is highly likely that blood flow drops during strong contractions. As WLU pointed out, there is also a vasodilation mechanism which is meant to increase blood flow through muscle by relaxation of vascular smooth muscle of the arterioles. As far as I know, the measurements have not been made. - Discussed and reviewed in van Leeuwen JL, Spoor CW. A two dimensional model for the prediction of muscle shape and intramuscular pressure. Eur J Morphol. 1996;34(1):25-30. QuietJohn (talk) 18:06, 28 May 2010 (UTC)

g

thats crazy!!!!!!!!!!!!!!!!!!! —Preceding unsigned comment added by 74.194.181.210 (talk) 01:30, 29 November 2007 (UTC)

Yes, it is crazy. The world is crazy in fact. I started reading the Muscle article and wanted immediatelly to correct the first paragraph. No way. It is protected. A request should be made! Then started reading the all article and… yes it is crazy. Hopeless. I read then some other articles, about other things. No, there will be no “request" for editing the text! I am muscle physiologist and I just think that the entiire project is a game. Not just the chapter on muscle. All is just a game. Makes people reading and playing science. This is wonderfull! One professional would spoil the game. Good luck!Parissorbonne (talk) 22:45, 15 June 2008 (UTC)

Etymology of the word muscle?

What I don't get is how you could use a derivative of a diminutive Latin word for 'mouse' to mean muscle. Can anyone explain how this evolved? SaintJimmy505 (talk) 02:09, 27 March 2008 (UTC)

Apparently the similarity is common in a large number of languages, because of the similarity between the movements of a mouse and a flexing human muscle, especially of the upper arm. At least, that's what the OED says. Tb (talk) 02:54, 27 March 2008 (UTC)

I am not sure either how that use of the word "muscle" evolved but I know that it is not of latin origin but of ancient greek. The reference is the oxford lexicon and their mistake can be attributed to ignorance or distortion of the truth. Both cases are very annoying. —Preceding unsigned comment added by Pariskal (talk • contribs) 13:55, 19 October 2008 (UTC)

The origin of the word μύς is not Latin. It is clearly Ancient Greek. It was used back then, and still today to mean both mouse and muscle. Please correct the first paragraph. Source: [3]. --147.102.141.205 (talk) 20:23, 12 January 2010 (UTC)

Your source does not support your claim. It says the word comes from Latin and that there is a cognate or related word in Ancient Greek. Cognates do not imply descent. --EncycloPetey (talk) 02:45, 13 January 2010 (UTC)

I read in the above source "Μύς was applied by Hippocrates whose example Celsus followed in musculus...etc"--Lunatic igbt88 (talk) 18:02, 13 January 2010 (UTC)

Something I'd like to know when I read this...

I actually came to this article hoping to find out which kind of animals have muscles, and which don't. I didn't see anything like that though :/ StroboX (talk) 19:15, 17 April 2008 (UTC)

Muscles are found in almost all animals except sponges. --EncycloPetey (talk) 02:46, 13 January 2010 (UTC)

Muscle Capacity

Is it true that a human only uses about 20% of each muscles capacity? —Preceding unsigned comment added by 193.71.107.39 (talk) 23:12, 17 April 2008 (UTC)

Strongest Muscle/Lever arm

I may just be confused by the way it's written, but I am pretty sure that it is supposed to say that the masseter has an advantage because of a longer, not shorter, lever arm. A short lever arm, as the article implies, gives less torque. (see:Torque) I think this needs to be fixed. Even if I am just misreading it, it should be clarified. —Preceding unsigned comment added by 138.67.151.126 (talk) 06:17, 25 April 2008 (UTC)

Incorrect Information

The last sentence of the Physiology section is incorrect: "The heart, liver and red blood cells will also consume lactic acid produced and excreted by skeletal muscles during exercise." How can red blood cells consume lactic acid without having mitochondria? In fact the opposite is true, Glucose is oxidized to Pyruvate in Red Blood Cells then reduced to lactic acid in order to regenerate the NAD+ needed for further glycolysis. The lactic acid then diffuses into the plasma and is absorbed by cardiac muscle and liver cells where it is oxidized back to pyruvate then acetyl-CoA and the citric acid cycle, etc. Anyway I can't edit it because my account hasn't been autoconfirmed for whatever reason so someone should fix that.

Do you have a source for red blood cells lacking mitochondria? My training is primarily in botany, so this is the first time I've heard about this feature of RBCs. I knew that mammalian RBCs lacked a nucleus, but didn't know they lacked mitochondria. --EncycloPetey (talk) 00:29, 2 December 2008 (UTC)

Mammalian RBCs do lack mitochondria (and ribosomes), they lose them during erythropoiesis. It's pretty uncontroversial, and I don't think it requires a citation. Fvasconcellos (t·c) 01:14, 2 December 2008 (UTC)

I didn't ask for a citation, I asked for a source. --EncycloPetey (talk) 03:02, 2 December 2008 (UTC)

Heres a recent article regarding the mechanism: http://www.nature.com/nature/journal/v454/n7201/abs/nature07006.html Repapetilto (talk) 23:39, 7 December 2008 (UTC)

Thanks. --EncycloPetey (talk) 19:23, 8 December 2008 (UTC)

But still noone has changed it...Repapetilto (talk) 23:24, 8 December 2008 (UTC)

and it continues to be incorrect...Repapetilto (talk) 20:59, 4 January 2009 (UTC)

There are THREE types of twitch muscle fibers, not two. Type III muscle is an "intermediate twitch" muscle which has characteristics of both the fast twich and slow twich muscle. —Preceding unsigned comment added by 207.213.182.148 (talk) 04:54, 2 March 2010 (UTC)

Um, no. The article currently describes the fiber types pretty accurately, including tonic, type 1, type 2a, type 2b, and type 2x. If you wanted to be *really* anal, you could point out that there are *twelve* types, including several only present in the embryo or fetus, and two that are unique to the masseters of rodents and carnivores. And that's from a decade-old paper - there are probably more, especially when you factor in things like that you can have co-expression of myosin isoforms in the same muscle cell and can mix-and-match bits of the myosin heavy and light chains. Mokele (talk) 18:09, 2 March 2010 (UTC)

I've tried to 'embrace' the fiber type fog in the motor unit page. QuietJohn (talk) 18:07, 25 May 2010 (UTC)

Too human- / vertebrate-oriented

This article is too human-oriented, ad its content applies at best only to bilateria or possibly only to vertebrates. The description of muscle cells applies only to myocytes. However cnidarians have mucsle cells known as "epitheliomuscular", because they are epithelial cells with specialised bases containing fibrils, (see Ruppert, E.E., Fox, R.S., and Barnes, R.D. (2004). Invertebrate Zoology (7 ed.). Brooks / Cole. pp. 103–104 and 112-113 and 116-117. ISBN 0030259827.{{cite book}}: CS1 maint: multiple names: authors list (link)) and ctenophores have myoepithelial cells, in which the epithelial component is reduced and is not exposed at the surface of the epithelium. The differences between these types of muscle cell are important for the classification and phylogeny of animals (e.g. The Significance of Muscle Cells for the Origin of Mesoderm in Bilateria). Hence this article should be re-titled, probably to "Verterbrate muscle", and another article, "Muscle", should cover the types of muscle I've mentioned, and other aspects that apply widely throughout the animal kingdom. --Philcha (talk) 09:49, 4 January 2009 (UTC)

Purple Aki

Purple Aki is famous for his connection to muscles. Perhaps he deserves a mention on this page?83.216.157.38 (talk) 17:02, 18 January 2009 (UTC)

Editing

Hello all! I hadn't edited in a while and I was about to but noticed the protection. Figured I make an argument first. Just gave the article a quick read and would offer a few posits. Muscle is mostly derived from mesoderm but some facial skeletal muscle and the smooth muscle of the great arteries (also eye and ear muscle structures) are derived from neural crest. Smooth muscle is also characterized as phasic, tonic, visceral, multi-unit, single-unit, etc. It would be nice to compare striated muscle differences between cardiac and skeletal muscle (intercalated disc, gap junctions, dyads or triads, excitation-contraction coupling differences, contractile isoforms, etc.) and compare striated to smooth. Differences in metabolism may not be appropriate but their energy substrate preference is notable between cardiac muscle (prefer fatty acids) and different types of skeletal muscle (glucose or fatty acids), then talk about fatigue. I can't remember if concentric and eccentric contractility are mentioned. I'm sure many posits have been made before but I was just pondering. Perhaps I should read the article more closely before my knee jerk reaction and anyone takes offense! . Regards GetAgrippa (talk) 00:49, 8 May 2009 (UTC)

Sex difference of muscle mass

I think it would be interested to add a bit about the difference in muscle mass between the sexes. Here is a good source. http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6T6H-4WBR6N8-1&_user=10&_rdoc=1&_fmt=&_orig=search&_sort=d&view=c&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=28c95508ab71e92681a315c226e1ba77

"Abstract

On average, men have 61% more muscle mass than women (d=3), a sex difference which is developmentally related to their much higher levels of testosterone. Potential benefits of greater male muscle mass include increased mating opportunities, while potential costs include increased dietary requirements and decreased immune function. Using data on males aged 18–59 years from the third National Health and Nutrition Examination Survey and including other relevant variables, fat-free mass (FFM) and/or limb muscle volume (LMV) are significant predictors of the numbers of total and past-year self-reported sex partners, as well as age at first intercourse. On the cost side, FFM and LMV are strong positive predictors of daily energy intake and strong negative predictors of C-reactive protein and white blood cell count, measures of native immunity. "--Deleet (talk) 22:36, 3 June 2009 (UTC)

Embryology

In this section appears the statement: "Epaxial muscles in humans are only the erector spinae and small intervertebral muscles, and are innervated by the dorsal rami of the spinal nerves." Is this really true? Reference?RayJohnstone (talk) 06:57, 18 December 2009 (UTC)

Yep, it's true. Practically all of your muscles are derived from the hypomere. Thanks for reminding me to finish up that section with a reference. Mokele (talk) 15:31, 18 December 2009 (UTC)

Thanks, but what is the evidence that the epaxial muscles are innervated by motoneurones with their axons in dorsal roots?RayJohnstone (talk) 14:30, 19 December 2009 (UTC)

They aren't, they're innervated by neurons from the dorsal rami, and it says that in the article. The roots of the spinal nerve are strictly split into sensory/motor (dorsal/vental respectively), but they fuse to form a spinal nerve, then quickly split again into the dorsal and ventral rami (which innervate the epaxial and hypaxial muscles). Mokele (talk) 15:04, 19 December 2009 (UTC)

Thanks, my mistake, I confused rami and roots. You can perhaps see why I got a bare pass in undergraduate anatomy. Still an interesting point about innervation.RayJohnstone (talk) 10:32, 20 December 2009 (UTC)

Innervation is a lot easier to understand from a comparative biology context. For instance, the reason the trapezius is innervated by a cranial nerve is because it used to be a gill muscle. Mokele (talk) 16:29, 20 December 2009 (UTC)

Introduction of this article needs to be more accessible

The introduction to this article is too technical and may have the effect of putting readers off. Per the guideline Wikipedia:Lead section#Provide an accessible overview, "It is even more important here than for the rest of the article that the text be accessible. Consideration should be given to creating interest in reading the whole article." Please can an editor with sufficient knowledge rewrite the introduction avoiding specialised terminology and placing the subject in a familiar context. For example, a first sentence might read something like "Muscles are the parts of animals' bodies that cause movement." Thank you. --MegaSloth (talk) 00:59, 21 January 2010 (UTC)

I plan on re-writing it - it's not easy to make something readable, but correct (for instance, your suggestion is actually wrong - ctenophores use non-muscular mechanisms to produce movement via beating comb-plates. Mokele (talk) 04:06, 21 January 2010 (UTC)

OK thanks for that. I've no doubt my suggestion may be wrong; if I thought I had the knowledge to write it correctly, I would have done it. What I was trying to indicate was the level of use of technical language and assumption of prior knowledge I would hope for. Cheers --MegaSloth (talk) 03:52, 31 January 2010 (UTC)

Layout suggestions and relationship to related pages

(Note This section has / may be edited to reflect feedback)

Briefly describe the 3 muscle types and their functions and link to appropriate (existing) Wikipedia pages. I've listed some functions below. I've also included some possible questionable 'functions' since the functions aren't intrinsic to muscles. Rather the muscles are integrated into other systems such as the sensory systems of vision and audition and also he alimentary system. I'm not a total expert, so may have some wrong. I'm also more familiar with vertebrate systems, so other viewpoints could add/change things.

Smooth

Thermoregulation (erector pilae)

Cardiovascular

Thermoregulation

Renal function

Vision (pupil control by iris muscles)

Alimentation

Excretion

Reproduction

Pulmonary

Cardiac

Cardiovascular

Striated

Movement

Thermoregulation (Thermogenesis and Thermoregulation)

Cardiovascular (Skeletal-muscle pump)

Sensory - Proprioception, vision (head/eye movement), audition (head/pinnae movement, middle ear muscles)

Alimentation - mastication, swallowing

Communication (Vocalization & facial expression)

Reproductive

Protection (Muscular defense, Abdominal guarding. Also, arteries and nerves usually buried under muscle)

Briefly describe their similarities and differences. Introduce contractile proteins, maybe note their similarity to other motile proteins (Intracellular transport, flagella...)

• Myosin - 18 types
• Actin
• Troponin

Maybe briefly describe which myosins are related to which types of muscles and fiber types. I'm a little confused by the IIc and IIx fiber types. Both of these designations refer to myosin types. I could only find 3 papers referring to IIc 'fibers' in a PubMed search and suggest that these 3 papers may be erroneous, really referring to fibers which expressed IIc myosin.

Organization of contractile proteins - sarcomeres in cardiac and skeletal muscle.
Basic contractile mechanisms.
Other muscle proteins, glycoproteins etc., specific to muscle.
Excitable membranes - include intercellular (gap) junctions for smooth and cardiac muscle.

Neurotransmitters and hormones.
Basic embryology of muscle.
Muscle evolution.

Move fiber types to Skeletal Muscle page.
Create a muscle anatomy page - and maybe a second one for human muscle anatomy. That can include the 'fascinating facts' related to human muscles. Microanatomy needs to be on the Smooth muscle, Cardiac Muscle and Skeletal Muscle pages.
Physiology should be consistently generic, focusing on similarities and briefly mentioning differences. leaving the specifics for the specialist muscle pages.
Nervous control also needs to be generic with specifics left to other pages. No need for cortical function here. Those other pages should include dorsal/ventral root descriptions for afferent/efferent skeletal muscle signals, sympathetic and parasympathetic innervation for smooth muscle and cranial nerve for cardiac muscle.
Same with exercise. Worth pointing out that exercise helps skeletal muscles and cardiac muscle (and possibly smooth muscle) but specific should be left for more specialized pages.
Ditto disease - The distinction should be made between muscle diseases such as the dystrophies, neuromuscular diseases such as spasticity, inflammatory diseases such as polymyositis and autoimmune diseases such as mysthenia gravis. Electomyography is more applicable to neuromuscular disease. It should also be noted that neuromuscular diseases result in (secondary) effects on muscles, such as high passive tensions and large connective tissue invasions and atrophy. Cardiac disease should also be mentioned. As should smooth muscle disease if anyone is aware of them (May be worth mentioning asthma, hypertension etc as diseases involving smooth muscle). It should also be noted that neuromuscular diseases result in (secondary) effects on muscles, such as high passive tensions and large connective tissue invasions and atrophy.
Ditto atrophy. Strength should move to skeletal muscle. Note: the paragraph as it stands contradicts itself. One sentence says te number of muscle fibers cannot increase.The next sentence says that muscle fibers may split. Hyperplasia is an increase in the number of muscle fibers.
The strongest human muscle section should be in a section on human anatomy or similar.
Efficiency refers only to skeletal muscle. Cardiac muscle may be similar (C. J. Barclay, C. Widén and L. J. MellorsInitial mechanical efficiency of isolated cardiac muscle. The Journal of Experimental Biology 206, 2725-2732 (2003). QuietJohn (talk) 07:50, 23 May 2010 (UTC)

Just trying to coordinate with Beland, Mokele and GettaGrippa before messin' with their efforts. I'll be happy to do some writing if I'm not at cross-purposes with others. Didn't Mokele also suggest a reorganization? - Just trying to work with other contributors who seem to be doing a reasonable job in a very large field.

_______________________Possible draft page_________________________

Introduction

Muscles are the motors which bring about movements in almost all animals. There are 3 basic kinds of muscle: smooth muscle; cardiac muscle and skeletal muscle, each subserving different functions in the body. Both cardiac muscle and skeletal muscle are known as striated muscle because the orderly organization of the contractile mechanism into sarcomeres appears as alternating dark and light bands, known as cross striations, when observed in a microscope.

Muscle contraction is accomplished by the contractile proteins, actin and myosin. The sliding filament theory describes the process by which the interdigitating filaments of actin and mysosin slide along each other to generate force and/or shorten the muscle. The energy source for muscle contraction is Adenosine triphosphate, usually originating from the breakdown of glucose by glycolysis or the Krebs cycle.

Muscles can cause movement of the organism itself or movement of internal organs. Cardiac and smooth muscle contraction occurs without conscious thought and is necessary for proper body functioning. Examples are the contraction of the heart and peristalsis of the gut smooth muscle which pushes food through the digestive system. Conscious,or voluntary contraction of skeletal muscle is used to move the body and can be finely controlled. Examples are movements of the eye, or gross movements like the biceps muscle of the arm.

Etymology

From Latin musculus, diminutive of mus "mouse"

Smooth muscle

Smooth muscle is distributed throughout the body, generally associated with internal organs. It contracts slowly and often rhythmically. Smooth muscle generally does not require voluntary effort to function since it is under the control of the autonomic nervous system. Smooth muscle often forms muscle layers surrounding the lumen of many internal structures such as blood vessels and the digestive tract.

Cardiac muscle

Cardiac muscle is restricted to the heart, responsible for pumping blood throughout the body. It has characteristics of both smooth muscle and skeletal muscle. Like many smooth muscles, the heart is not under voluntary control, has an intrinsic contractile rhythm known as heartbeats and the rate of beating is controlled by the autonomic nervous system. Like skeletal muscle, the heart muscle cells contract and relax rapidly and exhibit cross striations.

Skeletal muscle

Skeletal muscle is responsible for a vast majority of the external movements exhibited by animals. They come in many forms, often associated with tendons to transmit movement and force across joints. However, some skeletal muscles accomplish movement in the absence of bones or joints (e.g., the tongue and the elephant trunk). A majority of skeletal muscles may be controlled voluntarily although there are many instances, such as eye movements, breathing and even simply standing still when skeletal muscle activity is involuntary. Many of these same muscles may also be activated voluntarily, although a few, such as the stapedius and tensor tympani muscle of the middle ear cannot be activated voluntarily by most people (there are 'strange' refs (3 & 4) to this in the tensor tympani page. Skeletal muscle is the predominant muscle that is eaten as meat.

Other functions of skeletal muscle

In addition to generating movement, skeletal muscle has several other important functions. Shivering generates body heat (thermogenesis) for [warm blooded] animals. Cyclic contraction and relaxation of skeletal muscles (such as in walking or running) compress blood vessels, creating a skeletal-muscle pump to pump venous blood back to the heart. The muscle spindles and Golgi tendon organs of skeletal muscle provide proprioception, giving the nervous system information about limb position. The large bulk of many muscles also provides a protective function for more delicate tissues such as blood vessels and nerves. The abdominal muscle also protect the abdominal cavity and respond with a muscular defense in response to a blow to the abdomen, or with abdominal guarding by increasing abdominal muscle tone in response to abdominal pain. Recently, muscle has also become recognized as an endocrine organ, releasing myokines, such as Interleukin 6 which may increase glucose uptake and stimulates fatty acid oxidation.

(Muscles play an essential role in the proper functioning of many body systems which require movement to accomplish their purpose. Smooth muscle controls food passage through the digestive tract with sphincter muscles and peristalsis. They control the flow of blood through regions of the circulatory system. Tey are responsible for focusing the lens of the eye and adjusting the diameter of the pupil and contribute to thermoregulation by raising the hair to increase insulation.

Skeletal muscles orients the head, eyes and ear pinnae to adjust the field of vision and direction of hearing. They are used in a variety of ways for sound generation and communication. In the digestive tract, they move the jaw for chewing provide the musculature for swallowing and form the anal sphincter and bladder external sphincter.)

Intermediate and specialized muscle types

• Possibly mention distribution within animal kingdom and specializations.

• The electric organ of fish is a modified muscle.
• Insects
  • All insect muscles are striated (http://jcs.biologists.org/cgi/reprint/1/1/49.pdf). Flight muscles in some species contract multiple times per nerve impulse (Insect flight.
• Diagonally striated fibers
• Tonic twitch muscles in amphibians and reptiles.
  • Innervation

Contributions from following assimilated (thanks!) --EncycloPetey (talk) 04:37, 25 May 2010 (UTC) Mokele (talk) 00:26, 26 May 2010 (UTC) QuietJohn (talk) 19:17, 31 May 2010 (UTC)

_________End of draft - Additional notes for later sections (maybe)__________

Smooth muscle They alter the diameter of blood vessels to control blood flow, churn food in the stomach, seal off the stomach with the esophageal sphincter and the pyloric sphincter muscles and move food through the digestive tract by rythmic contractions in a process called peristalsis. They also adjust the diameter of the pupil of the eye and are reponsible for goose bumps in response to cold or fear. QuietJohn (talk) 08:09, 24 May 2010 (UTC)

Skeletal muscle mass

An average adult male is made up of 40–50% of skeletal muscle and an average adult female is made up of 30–40% (as a percentage of body mass)

In the Omron BF500 manual, these figures are very different. It says 33.3–39.3% for 18–39 year old males is the "normal" range, and 24.3–30.3% for females. I cannot find any source which would back up the claim that 40–50% would be a normal range for adult males.

In the absence of a reliable citation, I think the numbers should be deleted from the article. —Preceding unsigned comment added by 82.203.177.2 (talk) 10:08, 9 March 2009 (UTC)

I found this: http://books.google.com/books?id=ScfPjwF3BngC&pg=PA64&lpg=PA64&dq=human+percent+muscle&source=bl&ots=gGxWC-SLaT&sig=-agKMRlLowNB6CZLSDM7Xvn-S7o

which gives two peer-reviewed references for these numbers. Sadly, I don't have time right now to track them both down. Still, the numbers are accurate. Mokele (talk) 12:36, 9 March 2009 (UTC)

Women have more body fat so the have less body water content and less muscle mass as a percent of body mass. Regards GetAgrippa (talk) 00:49, 8 May 2009 (UTC)

I see a problem with the way the numbers are currently presented. The articles currently states that "An average adult male is made up of 42% of skeletal muscle". Since age, overweight and training are huge factors when it comes to this number, a mere "average adult male" is too generic; especially when a specific percentage is given. There should be more information about the base of this data. In the book from books.google.com which was link above and which gives similar numbers, body fat was of the "average male" was 15%-17%. I assume that muscle mass percentages of 40% and similar values are based on individuals with a fairly "optimal" BMI and an age of about 20-25, where age-dependent muscle degradation is not yet a factor. I therefore suggest to give additional information about what the percentages presented in this article are based on (especially age and body fat/BMI), because the "average male" in most "modern" countries certainly does not come close to 40% skeletal muscle mass; due to the fact that, for example, "as much as 64% of the United States adult population is considered either overweight or obese" (from the article on Overweight). --Tordeu (talk) 00:55, 2 April 2011 (UTC)

OK, but the article isn't about males in the US; it's about males in general, so we shouldn't base the numbers on US-specific data. And obesity doesn't rule out 40% muscle mass, since the common US definition is based on BMI - which doesn't even consider the possibility of increased muscle mass and is purely based on height and weight, regardless of fat percentage. You're making a lot of assumptions in your comments, when what we really need is a set of published studies with precisely defined statistics and caveats. --EncycloPetey (talk) 03:09, 2 April 2011 (UTC)

Brawn

I came to this article because in doing a crossword, the clue was "Brawn" & the answer "Muscle". Is this correct as there is no mention of a link between the two words in the article? If it is correct, maybe this should be mentioned in both this article & under "brawn", which also doesn't link to "muscle"!81.53.186.157 (talk) 13:14, 26 June 2011 (UTC)

Wikipedia is an encyclopedia. Maybe you should try wiktionary:brawn next time. --Fama Clamosa (talk) 14:11, 26 June 2011 (UTC)

Thanks for the feedback, I don't see that just because the information features in wikitionary excludes it from featuring in wikipedia... 2.10.207.122 (talk) 19:14, 26 June 2011 (UTC)

Wikipedia covers topics as articles, not the meaning of words. Dictionaries (like Wiktionary) cover the various meanings of words. So, Wikipedia is the place to find out more about a subject or topic, but Wiktionary is the place to find out about a particular word. The article on muscle is thus about the contractile tissue in animals, but you were looking for semantic relationships between words, which is properly the focus of a dictionary. That's not to say the information would be exculded from Wikipedia, but it might appear under an article about "strength" or about cultural perception of masculinity, rather than in the article about the contractile tissue. --EncycloPetey (talk) 19:18, 26 June 2011 (UTC)

Muscle Strength Citations Needed!

The muscle strength section makes a large number of claims, NONE of which are cited. This really needs to fixed. ebo60 —Preceding undated comment added 17:35, 29 June 2011 (UTC).

Suggested changes - comments

Ok, QJ, I've reviewed your suggestions on this page, and I'll try to go through them here:

Hope you don't mind me editing your comments -it may be the easiest way to communicate.

I invite you to do the same with mine - that way, there is no doubt what we are responding to.

• (QJ) Can we generate an outline to hang our discussion on? Maybe add to my Layout Suggestions.
  • If you want to edit, please do so. If you delete - maybe strikethrough until we reach a consensus.QuietJohn (talk) 19:02, 31 May 2010 (UTC)
    • No worries, but it may be a while - I'm a bit swamped with RL work at the moment.

Firstly, I think there's a bit much emphasis on the various types.

• (QJ) In my suggested changes intro? - I agree it shouldn't be much, but it seems important to introduce them and point out the common ground and differences between them. Mostly info that wouldn't be logical on the individual type pages. My existing "draft" was intended only for an introduction section. I planned to add much more (other content - not fiber types) in the main body of the page.

IMHO, while they shouldn't be ignored, the vast bulk of the text of this page should be focused on universal aspects of all muscles (structure of the sacromeres, contraction mechanics, microstructure, length-tension and force-velocity relationships, etc.). This especially goes for the intro. We shouldn't ignore them, but we also shouldn't make it all about the types and ignore their substantial common ground.

• (QJ) I think we agree! As an initial effort, I'd be inclined to briefly mention many properties and add other pages (such as contraction mechanics) on their own pages. I'm not sure how many of the suggestions you make here are type-specific (such as sarcomeres). Pennation, mentioned earlier would be another example of type-specific properties which are found on another (minimal) page. My feeling would be that pennation is a subset of Muscle Architecture. I think this would be the page to include "variations" from the typical trio of types - "vibratory" insect muscle, "catch" properties in molluscan muscle, and possibly intermediate types (e.g.., some molluscan buccal muscle seems intermediate between fast and slow), amphibian tonic striated muscle.
  • (MO) I'm iffy on the muscle contraction page. I think the best option would be to have some overlap - a sort of general paragraph giving an overview here, with the contraction page having more details. Sacromeres should be included here, though, since they're universal to muscle (though non-sarcomeric actin/myosin interactions occur in cellular motility). Pennation might have its own page, or might be better on the muscle anatomy page you proposed, however it's definitely more than just in undulatory locomotion - many of the major leg muscles in vertebrates are pennate (gastrocnemius, rectus femoris, etc.). IMHO, the "other" muscle types should probably just be dumped here for the moment - once we've got the info present, we can deal with it later.

Fiber types, particularly in relation to myosion isoforms (but also actin, troponin, and tropomodulin isoforms), is a mess in the actual scientific literature. I've actually been reviewing some of it for some upcoming experiments, and by and large, I think it would be best and most accurate to say some general stuff about fiber types, mention than recent data shows things as being more complex (variation in myosin isoform along the length a single fiber), and just up-front saying that science does not yet know exactly how the various isoforms correspond to the various fiber types and their contractile properties. More to the point, though, I think that entire issue should be dealt with in the Skeletal muscle page (which is where the lion's share of the variation occurs - there seems to be little fiber type variation in cardiac and smooth, AFAIK, but those are a bit outside of my field).

• (QJ) I think we agree - just a mention on this page then links to other pages.

Sadly, the "muscle evolution" bit is going to be rather short - we're only just starting to do proper digging in it, and I'm not 100% on some of the conclusions put forth.

• (QJ) Not even close to my specialization, but some interesting things seem to turn up in searches anyways.. (D.A. Dorsett and Julie B. Roberts. A Transverse Tubular System and Neuromuscular Junctions in a Molluscan Unstriated Muscle. Cell Tissue Res. 206, 251-260 (1980). Intermediate smooth/striated fiber.Buccal mass retractor muscles - show a variety of morphologies from apparently smooth to striated. Slow phasic muscles.)
  • (MO) Thanks for the ref, I'll dig that up and add it to my huge "to read" pile.

I do think it would be good to have a section on comparative muscle physiology - for instance noting that vertebrates have constant sarcomere length while inverts can vary it with evolution or even just with growth.

• (QJ) That's interesting - do you have refs? - mammalian sarcomeres lengths are well documented to vary by 20% (G. Golspink. Sarcomere length during post-natal growth of mammalian muscle fibers. J. Cell Sci. 3, 539-548 (1968), Appaji Panchangam, Dennis R. Claflin, Mark L. Palmer, and John A. Faulkner. Magnitude of Sarcomere Extension Correlates with Initial Sarcomere Length during Lengthening of Activated Single Fibers from Soleus. Muscle of Rats. Biophysical Journal Volume 95 August 2008 1890–1901).
  • (MO) That ref is probably the best - it's all relative. To a vertebrate biologist, 20% variation is huge. To an invert person, it's practically nothing - in one of her more recent papers (I forget which one, definitely 2009 or 2010) Sheila Patek reports increases of 600%+ in sarcomere length just within a single mantis shrimp species as it grows.
    • (QJ) Couldn't find the Patek ref on sercomere lengths, but found her others. Most seem to be on ant mandible muscles. Also found an interesting mammalian review with similar (~100%) sarcomere length ranges.. QuietJohn (talk) 21:00, 1 June 2010 (UTC)
      • (MO) Sorry, I think I got confused with some yet-to-be-published work she gave a talk on about a month ago. Still, the ant reference shows what I mean. I think you're misinterpreting the Lieber reference - he means that 94% of the contraction is across the plateau of the length-tension relationship. The sources he reviews show a range of vertebrate sacromere lengths (at optimal length) of 1.98-2.43 microns, with a mean of about 2.2 - pretty minimal variation in comparison to the vast variation in invertebrates.Mokele (talk) 21:08, 1 June 2010 (UTC)
        • (QJ) Take another look! Their Table 2 quotes minimum and maximum recorded sarcomere lengths. Some of the longest are double the shortest! QuietJohn (talk) 03:05, 3 June 2010 (UTC)
          • (MO) Those are ranges of lengths for a single sacromere as it stretches and shortens. To meaningfully compare sacromere lengths across species, you need to do so at a standard length, usually Lo, the optimal level of overlap on the plateau of the LT curve, which is what Table 1 shows. Vertebrates have an Lo of around 2.2 microns, give or take 0.2, while invertebrates can have an Lo of anywhere from 2-14 microns, often within the same animal in different muscles or within the same muscle of an individual as it grows. Mokele (talk) 19:53, 3 June 2010 (UTC)

I think we should either have a muscular anatomy page dealing with stuff like pennation, or stuff it into the skeletal muscle page. I don't think we need a human page, but rather just back-link human muscle pages to the stuff on muscular anatomy.

• (QJ) Yes, as I mention above, there is already something on architecture and pennation, but not much and very selective

I generally agree that exercise, disease, and atrophy need to be off-sourced with links, but electromyography should remain - while used on humans mostly for disease, it's widely used in comparative biomechanics to simply detect when muscles are on or off (and how intensely activated).

• (QJ) There are pages for muscle atrophy/muscle hypertrophy. I think should be mentioned on this page as it occurs in all muscle types (not too sure about smooth muscle). Not sure how, but we may also want to talk about trophic effects on muscle - neural, hormonal, growth factors?

Further thoughts? Mokele (talk) 22:24, 29 May 2010 (UTC)

Is there a way to map out related topics and their links to help design the section and integrate other pages? QuietJohn (talk) 19:02, 31 May 2010 (UTC)

Yeah, I think what we need is a diagram or something.

Anyhow, I'll comment more later, and I'll get to the comments you made on the skeletal muscle page soon. cheers! Mokele (talk) 20:28, 31 May 2010 (UTC)

• EP: There should definitely be a section on muscle development, including (a) embryological development (across species); (b) post-natal development; (c) hypertrophy and atrophy. There also ought to be a section on the major diseases and conditions that affect muscle function in humans. --EncycloPetey (talk) 06:03, 14 July 2011 (UTC)

Physiology

In the physiology section it is stated that there are 10 types of muscles yet only three types are mentioned in types sections of the article; smooth, cardiac, and skeletal (type I, IIa, IIb, and IIc). Either the remaining types of muscle need to be added to the types section or the first two sentences in the physiology section need to be changes. Mmhrmhrm (talk) 13:36, 8 August 2011 (UTC)There is also a sentence stating "...contraction is stimulated by electrical impulses transmitted by the nerves, the motor nerves and motoneurons in particular". Motor nerves are motorneurons, and the sentence does not make sense.

File:Muscle posterior labeled.png Nominated for Deletion

	An image used in this article, File:Muscle posterior labeled.png, has been nominated for deletion at Wikimedia Commons in the following category: Deletion requests July 2011 What should I do?
	A discussion will now take place over on Commons about whether to remove the file. If you feel the deletion can be contested then please do so (commons:COM:SPEEDY has further information). Otherwise consider finding a replacement image before deletion occurs. This notification is provided by a Bot --CommonsNotificationBot (talk) 21:11, 25 July 2011 (UTC)

Misleading links and a redirect

The "Anatomy" section divides into two subsections, "Gross Anatomy" and "Microanatomy". When the reader clicks either of these terms in the text, he (most probably) expects to get to the appropriate subsection. However, the links lead to another wikipedia articles, which deal with the notions in general, not related to muscles. This is certainly correct, but misleading. Does anyone has an idea how to solve this problem? Furthermore, a click on "Microanatomy" leads to a page which is a redirect to "Histology". Is this redirect not a mistake? 89.0.185.253 (talk) 05:29, 18 August 2011 (UTC)

Muscle growth DOES result in increased number of muscle cells!

The sentence below is based on a recently disproven myth:

"Contrary to popular belief, the number of muscle fibers cannot be increased through exercise; instead the muscle cells simply get bigger."

I remember a study a few years ago that showed a much higher number of cells in muscle biopsies of body-builders versus regular people. It concluded that unless body-builders just happened to be born with more cells, new muscles cells are created with muscle growth in addition to existing cells expanding. Yes, I'm too lazy to Google the study and update the page myself. 50.39.160.229 (talk) 02:49, 30 October 2011 (UTC)

Um... large number of cells as a result of bodybuilding, or that successful bodybuilders started with higher than average nubers of cells? That's a big difference, and according to you the paper was not able to satisfactorily resolve the issue. There would have to be a before-and-after study to demonstrate increase, not simply a study that noticed differences correlated with some phenomenon. Correlation is not causation. --EncycloPetey (talk) 21:45, 30 October 2011 (UTC)

Muscle types

Under Type II, we have A, X, and B. Or, A, D, and B. There has to be better names. Billytrousers (talk) 08:04, 6 December 2011 (UTC)

Believe it or not, those are the best names we have. It's becoming increasingly apparent as more sophisticated molecular techniques are being brought to bear on muscle that there's an exceptional diversity of myosins and associated proteins, many more types than previously realized. To what extent all are utilized or have functional effects is still pretty unclear. Just be glad I haven't gotten around to including "superfast" myosin, which is not super-fast nor is ever found in truly superfast muscles like the toadfish swimbladder (it's also more properly called masticatory myosin, though how good a name that is remains to be seen). HCA (talk) 18:51, 6 December 2011 (UTC)

Edit request on 23 December 2011

Please change "Though this postural control is generally maintained as a subconscious reflex, the muscles responsible react to conscious control like non-postural muscles," to "Though this postural control is generally maintained as an unconscious reflex, the muscles responsible react to conscious control like non-postural muscles," because "subconscious" is an outdated concept and is no longer taken seriously in academia.

foveaii 19:54, 23 December 2011 (UTC)

Done. --EncycloPetey (talk) 20:49, 23 December 2011 (UTC)

Bad english

"Skeletal muscle" or "voluntary muscle" is anchored by tendons (or by aponeuroses at a few places) to bone and is used to effect skeletal movement such as locomotion and in maintaining posture." There is a difference between AFFECT and EFFECT, please correct. — Preceding unsigned comment added by 118.208.157.49 (talk) 15:12, 21 April 2012 (UTC)

yes, there is a difference, but this is already correct. To "effect" movement means to cause it or bring it about, and that is the meaning intended here. To "affect" movement would mean to alter or change, and that is not the intended meaning. --EncycloPetey (talk) 17:17, 21 April 2012 (UTC)

Edit request on 9 September 2012

Minor typo correction.
In the following sentence, change intercalcated to intercalated.
Cardiac muscle fibers are interconnected by intercalcated discs,[8] giving that tissue the appearance of a syncytium.
Gzow (talk) 21:30, 9 September 2012 (UTC)

Done. WikiPuppies _bark ^dig 21:35, 9 September 2012 (UTC)

Unclear relationship between muscle length and strength

The section on muscle strength seems to claim that longer muscles are stronger, but shorter muscles are also stronger. This may need additional clarification to prevent misunderstanding.

"Some invertebrate muscles, such as in crab claws, have much longer sarcomeres than vertebrates, resulting in many more sites for actin and myosin to bind and thus much greater force per square centimeter."

"A shorter muscle will be stronger "pound for pound" (i.e., by weight) than a longer muscle. The myometrial layer of the uterus may be the strongest muscle by weight in the female human body." — Preceding unsigned comment added by 128.237.242.120 (talk) 11:44, 17 April 2013 (UTC)

I've clarified a bit, but a really thorough explanation and understanding would need substantial explanation and integration between this section, the sarcomere page, and the physiological cross-sectional area page, which is way beyond the scope of this article. At the whole muscle, just think of the muscle like a whole lot of springs arranged in multiple chains - more chains = more strength, but making chains longer won't affect strength because they're only as strong as the weakest link. For the sacromere, think of people pulling on a rock with a rope - a longer rope means you have more people and more force, but the speed expressed as rope-lengths-per-second will be lower because the people's speed is constant and the rope is longer. These are just crude analogies, but I hope they help. A thorough understanding of these would require reading a textbook on either biomechanics or muscle physiology (I recommend Biewenner's Animal Locomotion for the former, and Lieber's book for the latter, but that's just personal preference). HCA (talk) 15:34, 17 April 2013 (UTC)

These new findings should help clarify the matter 50-year-old assumptions about strength muscled aside93.37.57.231 (talk) 07:03, 1 August 2013 (UTC)paolo

Protected and requesting improvement

This page is requesting improvement of the lead section, but is also protected. I found it via the Wikipedia Community "Help out" section, but of course I can't edit it. Can the protection be removed or is it still needed? Zinios (talk) 08:22, 4 October 2013 (UTC)

The article is semi-protected and it can still be edited by editors who have done a little previous editing. If you click on the padlock sign it should explain this. Iztwoz (talk) 13:17, 4 October 2013 (UTC)

Muscle or Human muscle?

Hi guys! As I see the article has information only about human muscles. The first sentence refers to all animals after that the page contains facts about only human body. --Dymitr (talk) 21:52, 10 January 2014 (UTC)

"Muscle" is the general article, and so should cover muscle generally. As you noticed, the article currently has a strong human biology bias, but there are some bits of information pertaining to other vertebrates in the article, such as studies from bats, squirrels, and of embryonic muscle development in chickens. The human bias is one reason the article is not rated higher than it is currently. --EncycloPetey (talk) 05:17, 15 January 2014 (UTC)

While there's some human-biased stuff, most of it is actually fine - vertebrate muscle is actually quite conservative in many ways, and much of the structure, embryology, physiology, metabolism, and mechanics are universally applicable within the group. Now what we really are missing is the muscles of the invertebrates, which are tremendously diverse and interesting in all sorts of ways. HCA (talk) 15:44, 18 January 2014 (UTC)

Proposed merge with Muscle tissue

These articles are about the same topic and share the same meaning; it does not make sense to have two different topics, fragmented like this. Additionally, this page could be readily integrated into the existing Muscle page. LT910001 (talk) 05:01, 28 December 2013 (UTC)

Completely agree with proposed merge. Iztwoz (talk) 07:11, 28 December 2013 (UTC)

Support That article was in a rather poor state until rather recently which may be why it wasn't considered for a merge earlier. The merge would make it easier to access relevant information. CFCF (talk) 08:29, 28 December 2013 (UTC)

Oppose. The muscle tissue article already contains technical detail well beyond what ought to be in the Muscle summary article. The fact that the article has recently undergone significant improvement is not a reason for merger, but a reason to keep them separate and improve both. The Muscle article is a general article that should eventually be entirely written in summary style. The general article is already rather lengthy, despite the fact that it needs much further expansion. It includes discussion of cells, tissues, physiology, systems, coordinated function, organismal processes, and more. By contrast, the tissue article is specific to the tissue level of organization. The assertion in the proposal that the two are "about the same topic and share the same meaning" is incorrect. An article entitled "muscle" could comfortably discuss "deltoids" or compare specific muscles between organisms, whereas an article entitled "muscle tissue" would not. The two are not synonymous with each other, but rather one topic is a subset of the other. And just as we wouldn't merge in the articles on "neuromuscular disease" or "physical exercise", we shouldn't merge the article on the tissue structure, because the Muscle article is a general article. --EncycloPetey (talk) 17:18, 28 December 2013 (UTC)

A large part of the articles consists of duplicate information, which would do good to be in one place. I hardly consider muscle tissue to be significantly improved, rather it has been brought up to a level where it will no longer be deleted - previously it contained German text someone had transposed and not even bothered to translate. CFCF (talk) 07:47, 29 December 2013 (UTC)

Um...no, it doesn't consist in large part of duplicate information. As you yourself pointed out, most of the tissue article consisted of information that had not been translated from the German Wikipedia. It has now been translated. That material is not in the main article (and shouldn't be), so the articles do not consist of duplicate information. Rather, the main muscle article contains a section summarizing the tissue article. That's how summary style works on Wikipedia. --EncycloPetey (talk) 16:05, 29 December 2013 (UTC)

Oppose. "Muscle tissue" should discuss the architecture of smooth muscle, striated muscle and cardiac muscle. The article muscle without modifier should discuss the numerous muscles in the organism. JFW | T@lk 21:50, 28 December 2013 (UTC)

"Muscle tissue" is essentially a tautology, and what is covered in this article is of essential importance to what makes up a muscle. We do not have major articles on other topics arranged in this manner, eg main page "Liver" focusing on the organ, and then a separate article "Liver (organ)", also on the organ, which would be very confusing. Muscle tissue types are essential to what a muscle is, and there is no reason why we can't present both well on the same page, especially considering the page already contains much of this information. Having this precedent means we have a page that is not accessed much, will constantly lag behind the main page in quality, and serves only to duplicate the information stored therein. Any chance you'd be able to change your mind, considering most of the information is already duplicated? --LT910001 (talk) 10:38, 29 December 2013 (UTC)

Your analogy with "liver" does not consider the fact that there is only a single liver in an organism. By contrast, there are many different muscles, all of which are made up of muscle tissue. The term muscle happens to be used for both the individual structures as well as for the tissue of which they are composed. The tissue sense is an uncountable mass noun, whereas the sense for the organs is a countable noun in English. Because there is more than one meaning for the base term, "muscle tissue" is not a tautology. Yes, muscle tissue types are essential to what a muscle is, but the tissue types are not the muscles themselves. Yes, the subsidiary page will lag behind the main page...unless someone works on the subsidiary page. I persoanlly think it's great that the main page is ahead of the subsidiary specialized topics, becuase on most of Wikipedia that trend is the other way round. The individual highly-specialized topics usually get more attention than the general articles do. --EncycloPetey (talk) 16:05, 29 December 2013 (UTC)

Oppose - The thing about muscle is that it has multiple levels of organization, each of which affect the other, which differs from organs like the liver. For example, muscle contraction is subject to a force-velocity tradeoff at the sarcomere level, but macroscopic anatomy of the muscle (pennate vs not) can drastically alter the end effect at the whole muscle level (by, in turn, altering the actual speeds the sarcomeres are subject to at the sub-cellular level). In contrast, the liver cells perform a few metabolic functions, and the whole liver is just a LOT of these cells doing the same function - they'd all work the same regardless of the macroscopic organization of the liver. Consider bone instead - not only is there a "bone" article, but also articles about trabecullar and cortical bone, as well as the osteoblasts and osteoclasts that maintain it. This is because, like muscle, bones have multiple levels of organization, and their functions are not as simple as the function of the cells within them writ large.

Now, the organization of these articles, and parsing out what goes at what level, could use a lot of work. But that just means we should band together and fix them. HCA (talk) 16:50, 29 December 2013 (UTC)

There doesn't seem to be any consensus here, so I'm removing the merge tags. --LT910001 (talk) 05:26, 4 March 2014 (UTC)