Showing posts with label glycogen. Show all posts
Showing posts with label glycogen. Show all posts

Thursday, June 11, 2009

The importance of LSD

No... that does NOT have anything to do with Timothy Leary and psychedelic drugs. I am talking about Long Slow Distance.

Yes, my new training perspective involves running more slowly. Many training programs, such as SmartCoach from Runners World ,have us running at slow paces (and I almost always ignored them until it came time for tempo runs and speed work). But until last weekend, I never understood WHY.

Without boring everyone with an overload of science, you should run at about 80% of your maximum effort for that distance (maximum effort being a race) in order to train your body to utilize all the energy systems. In long distance running*, the body uses a combination of burning glycogen (muscle and liver glycogen and blood glucose) and fat. By training at a slower pace, we can train our body to "increase the contribution of fat to the overall energy production by more than 20%; therefore sparing muscle glycogen and extending the time until its depletion."** As most of us know, you hit "the wall" when your glycogen stores are depleted. You can avoid this by training at lower intensity to use more glycogen from the liver and bloodstream so that "efficient aerobic metabolism using fat can be maintained for a longer duration."**

Did I lose you yet?

How does all this relate to my own training for this past marathon? Well, first, I did most, if not all of my training runs at about 90% effort. My long pace runs were done at a higher effort than that (I think that some of them were closer to 95%). I was training my body to use glycogen, but not to become more efficient at using fat. In addition, I was never on my feet for the duration of my marathon. I think my longest run was 3:23. I didn't train my body to run for four hours. And it is not just one run. The body needs to adapt to running this long. Glycogen runs out in approximately two hours without utilizing other energy sources. Even with the use of Gu, I was feeling the lack of energy and "lead" legs around two and a half hours. Training, along with starting out too fast, contributed to my body's inability to have energy in the later miles of the marathon.

So let's get out there and build our endurance. Don't worry... I'll be talking about the speed. But the key to speed is specificity. You want to tailor your speed workouts to the race you are training for. More to come....

*long distance running is actually defined as any distance over a mile
**Marathoning- Start to Finish by Patti and Warren Finke.

LinkWithin

Related Posts with Thumbnails