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  1. #1
    Banned Jean Schernoff's Avatar
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    DOMS/AMS/Lactic Acid Build-Up

    Muscle Soreness

    I'm sure many of you know delayed onset muscle soreness (Has an acronym - DOMS), acute muscle soreness (AMS), and the burning sensation that you feel through/during the exercises.

    What causes muscle soreness?
    In very simple terms, in order to build strength you must overload the muscle. By overloading the muscle you cause micro-tears, when the muscle heals it becomes stronger. Movements that cause muscle soreness have been shown to produce localized damage to the muscle fibers. Chemical irritants such as histamine are released from damaged muscles and can irritate pain receptors in the muscle. Also, muscle damage often causes a slight swelling in the muscle tissue which creates enough pressure to stimulate these pain receptors. However, it has been shown that some swelling may persist even after the muscle soreness has disappeared. So, it is thought the pain receptors either gradually adapt to the swelling or to some other factors present.
    Also it was shown that muscle soreness happens during eccentric part of lifts (negative lifts). An example would be when you do bicep curls, you stretch out (lengthen) your muscle while contracting it.

    What causes DOMS?
    Although scientists aren't 100% sure about it, it is said (This was shown as a valid statement) that delayed muscle soreness is due to microscopic tearing of the muscle fibers. People who are new to exercise or carry out an exercise programme which is more intense than they are used to, more often than not, suffer from DOMS. But not only beginners, a person of any other fitness level can suffer from DOMS too. This can be due to drastically changing your workout routine, or over-loading the muscle with the weight.
    In addition to microscopic tearing, swelling may take place in and around a muscle, which can also contribute to delayed soreness. Such swelling increases pressure on the neighboring structures, resulting in greater muscle pain and stiffness. Eccentric muscle contractions tend to cause both microtearing and swelling.
    Although your muscles hurt experiencing the delayed soreness, there is no permanent damage associated with DOMS. DOMS ususally happen within 12-48 hours after the workout, and exceeds for 3-5 days. In extreme cases, if that soreness doesn't go away within 7 days and/or exceeds 7 days, contact the doctor.

    Some people say that muscle soreness is when your muscles grow. This statement is false. Muscle soreness doesn't in any way have relationship with protein synthesis (muscle growth).

    So, should I train while my muscles are sore or/and experiencing DOMS?
    If the muscle soreness is minor, then you can train. In any other cases when your muscles hurt when you contract them, you should not train, if you do - this might cause over-training. For all of those who want to know what overtraining is, read Travis Stenerson's article on it at https://igoodies.000webhostapp.com/?viagra=showth...=overtraining.

    What causes AMS?
    Acute muscle soreness (Has an ancronym - AMS) is experienced during the "pump" of the muscles. It usually disappears within a couple of hours after a workout. It is due to blood over-flow in the muscles. It usually makes our muscle a bit bigger but our muscles take its normal shape after the AMS is over. AMS doesn't have any relationship with protein synthesis neither.

    What causes lactic acid build-up?
    Lactic acid build up is most commonly associated with the intense burning pain felt in your muscles after an intense effort. Recently, a lot of attention has been focused on reducing lactic acid build so you can exercise at a higher intensity for a longer time and improving performance. For more info on lactic acid build-up, read my article at "Post Your Own Articles" Section of those boards called "Carbohydrate Process 911". You'll find it there.

    For those of you who didn't figure it out yet, lactic acid build-up also doesn't have any effects on protein synthesis.

    How can I eliminate the DOMS?
    • Stretch - there's not a great deal of physiological support for stretching as a way to eliminate the cause of soreness or repair the tissue damage, but it may make you feel better temporarily. The goal is not to increase flexibility, but to take the muscles through a comfortable range of motion.
    • Move - physical activity tends to temporarily eliminate the muscle soreness after a workout. It may be difficult to begin, but you'll feel better while you're doing it. Keep the intensity low.
    • Massage - muscle massage has received a great deal of support as a way to help muscles recover.
    • Hot tub it - another popular method for recovery, this brings not only relief but a feeling of relaxation as well.
    • Evaluate your program - occasional discomfort after a workout is not uncommon. However, severe pain, or intense soreness on a regular basis may indicate that your workout is inappropriate for your body's adaptation capabilities. Back off on intensity if necessary to ensure you don't over-train or get injured.

    Conclusion
    I'll repeat it again, muscle soreness doesn't have any effects on protein synthesis. And for all of you who has been scared of muscle soreness can forget about the fear. Muscle soreness doesn't have any negative effects on you unless this soreness exceeds for a long time. An example would be when you need to contact your doctor is when DOMS surpasses 7 days. And you're not supposed to be training while your muscle are sore, unless it is a minor soreness.

    Sincerely,
    Jean
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    Thumbs up it is an article that everybody should read

    thanks for the good article
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    Hi,

    to add to the above, here's a two part current (sept 2009) review of recent research on

    part 1: what's DOMS and what doesn't work
    part 2: what does seem to work - depending on how DOMS is measured.

    best,
    mc
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    This is CNN, CNN, CNN.... J.X's Avatar
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    This was/is a great article, I was just reading on-line about this tonight. I wonder why this person got Banned??............Weird.
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    Originally Posted by J.X View Post
    This was/is a great article, I was just reading on-line about this tonight. I wonder why this person got Banned??............Weird.
    dunno, but just fyi, there are a number of inaccuracies in the post based on what we know about our physiology over the last ten years.

    we don't know for instance that doms is the result of tearing at all - and the consensus is likely it isn't.

    AMS as it's called in this post, likewise is a bit off and is not correlated to the pump and we know for a fact that lactic acid has nothing to do with the "pain" associated with muscle pain.

    That to the best of our knowledge may be either a calcium leak or potentially an upset in the pH balance (just a slight imbalance can cause significant distress).

    Similarly, increasing endurance is not about reducing lactic acid so much as improving the buffering of the H+ ions. Lactate is actually one of the energy systems we use (like the oxidative and glycolytic) when we work out.

    And finally DOMS is not related to load per se (eg a heavy weight) but again, to the best of our knowledge, to unfamiliar eccentric contraction patterns - load can be a part of that, but it doesn't have to be. So for instance researchers will often induce DOMS for studies by having a person *walk* backwards on a slightly inclined treadmill. No big deal with load; just an unfamiliar eccentric pattern.

    best
    mc
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    Addicted to Peanut Butter Ivankannan's Avatar
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    I am slightly confused here. Hope somebody helps me.
    If I don't feel any muscle soreness from my workouts, does that mean they are ineffective?
    Shut the F up and Squat
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    Originally Posted by Ivankannan View Post
    I am slightly confused here. Hope somebody helps me.
    If I don't feel any muscle soreness from my workouts, does that mean they are ineffective?

    No it doesn't mean they're ineffective
    no pain = no pain
    mc
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    Drastically increasing my protein intake from about 70ish grams a day to nearly 200g significantly reduced DOMS immediatly. I had it really bad before, sometimes went on for 7-8 days but now only have minor Doms for a day or so.
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    Originally Posted by mc- View Post
    dunno, but just fyi, there are a number of inaccuracies in the post based on what we know about our physiology over the last ten years.

    we don't know for instance that doms is the result of tearing at all - and the consensus is likely it isn't.

    AMS as it's called in this post, likewise is a bit off and is not correlated to the pump and we know for a fact that lactic acid has nothing to do with the "pain" associated with muscle pain.

    That to the best of our knowledge may be either a calcium leak or potentially an upset in the pH balance (just a slight imbalance can cause significant distress).

    Similarly, increasing endurance is not about reducing lactic acid so much as improving the buffering of the H+ ions. Lactate is actually one of the energy systems we use (like the oxidative and glycolytic) when we work out.

    And finally DOMS is not related to load per se (eg a heavy weight) but again, to the best of our knowledge, to unfamiliar eccentric contraction patterns - load can be a part of that, but it doesn't have to be. So for instance researchers will often induce DOMS for studies by having a person *walk* backwards on a slightly inclined treadmill. No big deal with load; just an unfamiliar eccentric pattern.

    best
    mc
    I believe you answered your own question...it's the H+ ions that alter the pH and cause a burning sensation. There really isn't such a thing as 'lactic acid.'
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    Originally Posted by FutureFoe View Post
    I believe you answered your own question...it's the H+ ions that alter the pH and cause a burning sensation. There really isn't such a thing as 'lactic acid.'
    who answered who's question?

    of course there is such a thing as lactic acid: it's an energy source.
    so i'm a bit lost.
    i've been fighting the good fight to let folks know that we don't get mucle burn or ache from lactic acid or blood lactate.

    so yup, lost as to your point.

    best
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    Originally Posted by mc- View Post
    AMS as it's called in this post, likewise is a bit off and is not correlated to the pump and we know for a fact that lactic acid has nothing to do with the "pain" associated with muscle pain.

    That to the best of our knowledge may be either a calcium leak or potentially an upset in the pH balance (just a slight imbalance can cause significant distress).



    First of all, I think we're in agreement as I misinterpreted this portion of your post. It was a good post, I guess I was just nit-picking. Second of all, let me clarify my thoughts. Lactic acid isn't an energy source, blood lactate is. Lactic acid cannot be created in Human tissues under normal conditions, there simply isn't enough hydrogen ions present to produce any acid. But, from everything I've read, an upset of pH is the acute cause of muscle soreness, while calcium leaking into the sarcoplasmic reticulum is probably the cause of long term soreness (DOMS).
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    Originally Posted by FutureFoe View Post
    First of all, I think we're in agreement as I misinterpreted this portion of your post. It was a good post, I guess I was just nit-picking. Second of all, let me clarify my thoughts. Lactic acid isn't an energy source, blood lactate is. Lactic acid cannot be created in Human tissues under normal conditions, there simply isn't enough hydrogen ions present to produce any acid. But, from everything I've read, an upset of pH is the acute cause of muscle soreness, while calcium leaking into the sarcoplasmic reticulum is probably the cause of long term soreness (DOMS).

    Hmm. this is a wee bit different to my understanding and our labs.
    A good ref is Bioenergetics by brooks on lactic acid. Muscles threshold is about 3g/kg (table 3.3 of the latest edition). Lactic acid is formed around glycolicis, which then gives off H+ ions.
    WHat's left forms with sodium and potatsium ions to get the salt lactate. The Cori cycle uses the lactate to convert into pyruvate for energy (ATP), true, but we don't get to lactate without that first process in glycolosis. And it's the what used to be called lactic acid threshold that is really about the capacity to buffer the H+ ions (acidosis) from the breakdown of lactic acid that gets into wanting to hurl, as chemoceptors in the nervous system respond to this imbalance.

    main thing: lactic acid has nothing to do with DOMS, nor of fatigue in low-mid intensity exercise.

    i'll look for some refs.
    best,
    mc
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    Originally Posted by mc- View Post
    main thing: lactic acid has nothing to do with DOMS, nor of fatigue in low-mid intensity exercise.
    Agreed...and I know this was the whole point of the thread, sorry if I got off topic.
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    This is CNN, CNN, CNN.... J.X's Avatar
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    Originally Posted by mc- View Post
    who answered who's question?

    - of course there is such a thing as lactic acid: it's an energy source.
    - we don't get mucle burn or ache from lactic acid or blood lactate.

    mc
    Good to know, I thought the soreness was Lactic Acid build up in the muscle or the rise in blood lactate.

    Originally Posted by mc- View Post

    - there are a number of inaccuracies in the post based on what we know about our physiology over the last ten years.

    - don't know for instance that doms is the result of tearing at all - and the consensus is likely it isn't.

    - AMS as it's called in this post, likewise is a bit off and is not correlated to the pump and we know for a fact that lactic acid has nothing to do with the "pain" associated with muscle pain.


    O.K. - DOMS/AMS is NOT assoc. w/tearing - Pain not equal to Lactic Acid build up


    That to the best of our knowledge may be either a calcium leak.......

    Similarly, increasing endurance is not about reducing lactic acid so much as improving the buffering of the H+ ions.

    Make's Sense!

    Lactate is actually one of the energy systems we use (like the oxidative and glycolytic) when we work out.

    I Got this from something I read, a paradigm shift in most peoples thinking who just work out and are not aware of the energy systems as you spelled them out and how they work exactly.

    And finally DOMS is not related to load per se (eg a heavy weight) but again, to the best of our knowledge, to unfamiliar eccentric contraction patterns - load can be a part of that,

    Interesting!

    So for instance researchers will often induce DOMS for studies by having a person *walk* backwards on a slightly inclined treadmill. No big deal with load; just an unfamiliar eccentric pattern.

    Cool, makes sense to test it this way.
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    thank you
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    Muscular acidosis (aka H+) are released by 3 factors:

    1. ATP -> ADP + P + H+

    2. Oxidation of glucose... specfically formation of NADH from NAD by the following reaction

    Glycolytic/kreb's substrate + NAD+ ---> Oxidized glycolytic/kreb's substrate + NADH+ + H+

    C6H12O6 releases 10 H+ ions in the formation of NADH.

    The other two hydrogen atoms for glucose are kept in the QH2 or FADH2 reaction used in electron transport (put into the mitochondrial H+ gradients).

    3. Buffer of carbon dioxide in the blood

    CO2 + H2O ---> H+ + HCO3-


    And yes, increases in mitochondria can buffer acidisis from occurring which leads, naturally, to increased aerobic pathway endurance. Increases of mitochondria = ability to buffer more H+ ion gradients. H+ ion gradients are used for synthesis of ATP by ATP synthase.

    Lactate is indicative of high intensity in the glycolytic pathway, but not caused by it. Nor does it cause soreness, fatigue, acidosis, etc.

    There's some more myth debunking here including the various ACTUAL causes of soreness.
    http://www.eatmoveimprove.com/2009/1...t-lactic-acid/
    Last edited by braindx; 11-21-2009 at 08:29 PM.
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    aside

    Originally Posted by braindx View Post
    M
    There's some more myth debunking here including the various ACTUAL causes of soreness.
    http://www.eatmoveimprove.com/2009/1...t-lactic-acid/
    You state in that article
    "Some “recent” articles in the media here and here have given the public an image that lactic acid is a fuel.

    This is false."

    I don't think that's quite the case. If you look at Brooks, say the fifth edition of Exercise physiology, you'll see the stuff he's famous for: the lactate shuttle. Indeed, he's foregrounded that lactate itself is actively oxidized - used as a preferred fuel - by heart and muscle cells, esp. in type II fibers in exercise.
    You also point to MCT1 and use of glucose. Right, that's part of it: mct1 is the lactate/pyruvate transporter in the muscle; gluconeogenisis in one cell can supply fuel for oxidation to another cell - hence shuttling lactate as fuel. BUT a lot of lactate is not shuttled, but is used directly within the producing fiber as fuel.

    As said, brooks is probably the leading expert on this topic, but it's pretty much accepted, esp since about 2005 as i understand it.. so the articles you cite mentioning it are not far off. just a bit slow to catch on.
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    Originally Posted by mc- View Post
    You state in that article
    "Some “recent” articles in the media here and here have given the public an image that lactic acid is a fuel.

    This is false."

    I don't think that's quite the case. If you look at Brooks, say the fifth edition of Exercise physiology, you'll see the stuff he's famous for: the lactate shuttle. Indeed, he's foregrounded that lactate itself is actively oxidized - used as a preferred fuel - by heart and muscle cells, esp. in type II fibers in exercise.
    You also point to MCT1 and use of glucose. Right, that's part of it: mct1 is the lactate/pyruvate transporter in the muscle; gluconeogenisis in one cell can supply fuel for oxidation to another cell - hence shuttling lactate as fuel. BUT a lot of lactate is not shuttled, but is used directly within the producing fiber as fuel.

    As said, brooks is probably the leading expert on this topic, but it's pretty much accepted, esp since about 2005 as i understand it.. so the articles you cite mentioning it are not far off. just a bit slow to catch on.
    Okay,

    Lactate shuttle, in most muscles, is used to eliminate lactate accumulation by shunting it into the blood stream. Most of it is uptaken by the liver and reconverted into glucose via Cori cycle in the liver.

    Some tissues, like you said, can absorb blood lactate (namely brain, heart, some slow twitch muscles). Absorbing it as a metabolite doesn't mean it's fuel. It first has to be recoverted to pyruvate and goes through all of the necessary oxidation of the citric acid cycle/electron transport/et al.

    Basically, it's an intermediary metabolite for energy production. It's not a "fuel" just because everyone thought it was a "dead end" reaction and found it that it does get reprocessed by other tissues or used by the tissues its in.

    The body doesn't produce/store/utilize lactate as it does the other fuel sources like carbs/glucose, protein, fatty acids (and to a lesser extent nucleic acids). It's generally a by-product of high intensity which can be utilized by the brain/heart/slow twitch muscles under high intensity given that one trains the body for such use.

    It's not a "fuel" by itself.

    -----------------

    Basically, if we disagree sure.

    If you consider production of carbohydrates from the Cori cycle (lactate shuttled) itself as a fuel then I can see how you would consider lactate shuttled directly to tissues as a fuel.

    I see it as dispersing the energy load from muscles through intermediary metabolites. It's an intermediary metabolite of glycolysis -- no dead end, no energy source.
    Last edited by braindx; 01-19-2010 at 04:45 PM.
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    Originally Posted by braindx View Post
    Okay,

    Lactate shuttle, in most muscles, is used to eliminate lactate accumulation by shunting it into the blood stream. Most of it is uptaken by the liver and reconverted into glucose via Cori cycle in the liver.

    Some tissues, like you said, can absorb blood lactate (namely brain, heart, some slow twitch muscles). Absorbing it as a metabolite doesn't mean it's fuel. It first has to be recoverted to pyruvate and goes through all of the necessary oxidation of the citric acid cycle/electron transport/et al.

    Basically, it's an intermediary metabolite for energy production. It's not a "fuel" just because everyone thought it was a "dead end" reaction and found it that it does get reprocessed by other tissues or used by the tissues its in.

    The body doesn't produce/store/utilize lactate as it does the other fuel sources like carbs/glucose, protein, fatty acids (and to a lesser extent nucleic acids). It's generally a by-product of high intensity which can be utilized by the brain/heart/slow twitch muscles under high intensity given that one trains the body for such use.

    It's not a "fuel" by itself.

    -----------------

    Basically, if we disagree sure.

    If you consider production of carbohydrates from the Cori cycle (lactate shuttled) itself as a fuel then I can see how you would consider lactate shuttled directly to tissues as a fuel.

    I see it as dispersing the energy load from muscles through intermediary metabolites. It's an intermediary metabolite of glycolysis -- no dead end, no energy source.

    THe body doesn't store pyruvate like fat either - does that make it an intermediary too, not a fuel?

    Look it's nothing personal about a disagreement.
    It's not me callign lactate a fuel.
    It's the research in teh area that's come to that position
    and i'm not sure where you get "most of it is taken up by the liver"

    Again, i'd draw your attention to the work by brooks especially, i'm sure your library will have his exercise physiology text - longer explanations there than the papers.

    best
    mc
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    Pyruvate is an intermediary metabolite...

    Basically, I'd say anything that doesn't come directly from body storage or food in abundance isn't really itself a fuel. Just one step in the metabolic process for energy.
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    Originally Posted by braindx View Post
    Pyruvate is an intermediary metabolite...

    Basically, I'd say anything that doesn't come directly from body storage or food in abundance isn't really itself a fuel. Just one step in the metabolic process for energy.
    it's interesting that you say "i'd say"
    that's bold.
    have you checked this with your profs? have you looked at brooks? and the rationale there for designating lactate a fuel, and the pretty on board assessment by folks in bioenergetics saying likewise?

    just curious,
    mc
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    Let's put it this way...

    If say citrate was considered a useless molecule for some amount of time, and then research came out and showed it was used for energy -- what do you think?

    Citrate as you know is a metabolic component in the kreb's/CAC/etc. cycle.

    Of course anything can be designated as a fuel if you use similar rationale.


    I've definitely read Brook's stuff and, at least in my mind, clearly points to it as a key intermediary metabolite between energy processes. For example,

    http://www.ncbi.nlm.nih.gov/pubmed/17465603

    If you have any further information which you believe contradicts my position let's discuss further. Currently not at a uni so I don't really know any profs to discuss with.
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    Good Article
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