Friday, May 19, 2006

Lactic Acid Is Your Friend?

A friend sent me two links to articles describing recent research suggesting that lactic acid, the much-aligned molecule among athletes, is actually used as fuel by the muscle cells. Previously, it was preached that at a certain point, the "lactate threhold," the body started producing too much lactic acid, resulting in a significant decline in athletic performance. To quote the Berkeley article, this research suggests that
  • muscle cells use carbohydrates anaerobically for energy, producing lactate as a byproduct, but then burn the lactate with oxygen to create far more energy. The first process, called the glycolytic pathway, dominates during normal exertion, and the lactate seeps out of the muscle cells into the blood to be used elsewhere. During intense exercise, however, the second ramps up to oxidatively remove the rapidly accumulating lactate and create more energy.
  • Training helps people get rid of the lactic acid before it can build to the point where it causes muscle fatigue, and at the cellular level, Brooks said, training means growing the mitochondria in muscle cells. The mitochondria - often called the powerhouse of the cell - is where lactate is burned for energy.
I think these are interesting articles because there has been so much hype about "lactic acid thresholds" and there are even tests that supposedly measure this level. It appears that what we may actually be measuring is muscle cell mitochondrial density.

The links are:
Berkeley Article
New York Times Article

Monday, May 08, 2006

Swim start at the Wildflower Triathlon, 2006

and they're off!
and they're off!,
originally uploaded by annetics.
This is one of the early waves of the Wildflower Triathlon, long course, starting in the morning on May 6, 2006. The water at Lake San Antonio was the highest it has been in anyone's recent memory and was also pleasantly warm.

Wildflower Triathlon, Long Course 2006

Last weekend, I went down to compete in the Wildflower triathlons. Saturday, I did the bike leg in a relay for the long course, which turned out to be quite challenging. I had a bit of difficultly with my blood sugars around mile 30, which really sapped my energy for the rest of the hilly ride. But I finally made it in a slow time of 3:51. After that sad performance, I decided to go ahead and race the next day in the Olympic course, which went much better. I managed to keep my blood sugars stable throughout the race and even enjoyed myself a bit. I had decided not to worry too much about my time and just enjoy the day.
This picture shows the transition area of the long course race. You can see the swim course as well; competitors race in a clockwise direction around the buoys. It is farther than it looks!