Thursday, July 17, 2003
Big Mac
Everybody remember Creatine? That's what Mark McGwire was popping a few years back. I've been (slowly) reading "Prime Mover: A Natural History of Muscle", here's what is had to say on the role of creatine:
Oddly enough, at no time does a muscle contain much ATP. Running at top speed on ATP alone, a human would run out, having converted it all to ADP, in two to four seconds. So we can't go far without reconstituting ATP from ADP. Another chemical, creatine phosphate, provides the immediate source of both energy and phosphate; splitting off a phosphate from creatine provides the wherewithal to make ATP from ADP. But we haven't much creatine phosphate either, not even enough for twenty seconds of hard running. For a longer run, we bring into use the fat and starchy stuff (glycogen, essentially a chain of sugars) in the muscle. That can keep a runner going for an hour or so. For still longer bouts of activity, fat and carbohydrates have to be moved to the muscles from the liver and the body's fatty tissue.
So in theory I can see how having creatine phosphate in your system helps you train/work out. I'm not sure just ingesting the stuff will do you any good though.
Here's a link to the book:
posted by David 11:33 AM
