Maybe you all have already read this, but it's a short article on what lactic acid really is. Apparently, research shows that lactic acid is fuel for your muscles, not the negative build-up that you sometimes read about. It's used by mitochondria, which are increased by hard training. W/o adequate training, there are not enough mitochondria to make use of the lactic acid and it's wasted. Check it out, much better said in the article.

NYTimes
http://www.nytimes.com/2006/05/16/he...ion/16run.html
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