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Medical Lactate and exercising

  1. May 5, 2008 #1


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    Is it important to drain your leg muscles of excess lactate after running in order to avoid cramps? Is that what stretching does? Can you get the lactate into you blood just by shaking them?
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  3. May 6, 2008 #2

    jim mcnamara

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    I dunno about 'draining' anything from your legs by stretching. Lactate builds up primarily from anerobic respiration. This comes about as oxygen levels in muscle tissue get low.

    People who are in very good shape still stretch, but their lactate buildup is less than someone who is in poor shape.

    Stretching is more of a way to get stiff muscles and connective tissue loosened up so that it is not damaged as readily by extreme demands. A more exact discussion meant for runners:
  4. May 6, 2008 #3
    You don't really drain lactctic acid from your legs. I don't exactly remember how, but lactic acid can be run through the citric acid cycle once the muscles in your legs have enough oxygen to do so. (The reason that your cells produce lactic acid in the first place is because your cells need more oxygen than they're getting, so in order to make quick atp, they skip the whole aerobic respiration part and get atp through lactic acid fermentation)

    I'm big into distance running, and I find that the best way to get that burning sensation out of your legs from the build up of lactic acid is to just slow down the pace and let things work themselves out. Cramps, however, are not caused by build up of lactic acid as much as a few other things. The major culprit there is either an imbalance of sodium and potassium (usually less sodium) or dehydration. To get rid of cramps, eat foods rich in potassium through the day and drink something like half water and half gatorade while you work out. You can even just put some salt in your water(just make sure you don't have too much to drink at once, because then you'll get those side cramps or side stiches.) However you do it, just make sure that your body is getting a good balance of water and sodium before, during, and after a workout.

    Also, if your legs are sore the next day, its good to stretch them and go for a short, easy run. The running will usually work out problems as long as you don't do too much.
  5. May 6, 2008 #4


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    As has been pointed out, stretching won't do anything for lactate build-up, since that's intracellular. What it may help out with is simple venous blood return. In the lower limb, especially, muscle contractions aid in circulation by helping compress veins to move blood back up counter to gravity. But I'm not completely sure if that's a function of stretching post exercise, or only the stuff jim talked about above.
  6. May 11, 2008 #5
    I thought only pyruvate was run through the citric acid cycle...?
  7. May 12, 2008 #6
    I think that the effect of stretching is limited. After a workout you should eat something and then do a light workout. That light workout will help you to recover faster. I've read that many athletes do this. I also used to do this when I exercised twice a day. I would exercise before lunch. Then, after lunch I would do a light workout which helped me to recover enought to do an intensive workout before dinner. Then after dinner I would do a light exercise again.
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