Breaking the Wall

Running economy is one of the more elusive aspects of improving performances. I think it has more to do with chemical processes in muscles than any one part of the body. Some runners use less oxygen to maintain certain speed than others. Most important predictor of running economy seems to be the proportion of slow twitch fibers, because they are more efficient in using oxygen. This is more significant than biomechanics. Have you had your proportion of slow twitch and fast twitch fibers measured? I would think you have predominantly slow twich fibers, given that your best event is the marathon. Anyway, you can't do anything about that, short of muscle transplant :), which would probably be considered doping. Another predictor, which certainly can be influenced by training is the cumulative number of years running, but I think you must have hit the limit in that. I can't imagine 22 years of consistent running not maxing out on this. This leaves one last predictor - a combination of biomechanical characteristics. It's pretty vague, and the problem is that it is a combination of how you're put together, not any one individual part. Pfitzinger mentions length of femur relative to tibia, but again, you can't improve things like that.

All of this means that it is very hard for an elite athlete like you to increase running economy (not that you shouldn't try). I think that at your level, you need to consult with serious experts in physiology and running economy researchers, undergo some testing and see if there are some recommendations in exercises or certain workouts specifically for you that may help. What worked for others may not work for you. Good luck!

Sasha, Merry Christmas. Thanks for the blog and all your supporting comments. See you at the races.

Brent and Sylvia

Brent,Sylivia:

Thanks - Merry Christas to you and everyone else.

Maria - I have some evidence that makes me think the poor biomechanics is my limiting factor. I can jump 27.50 in a ten-fold jump, which according to the charts should give me 11.8 in a 100 meter sprint. My best 100 meters is 13.9. My interpretation is that the strength and the explosive power is there, but for some reason I cannot use it while running.

Also, I have a VO2 Max of 75, and can race a half marathon at 92% of my max HR. With this level of aerobic capability, I should be able to run a 5 K in 14:10. My best 5 K time on an honest (not extremely downhill) course is 15:37.

I've never had a biopsy done. It would be interesting. However, I do not anticipate finding an unusual proportion of slow-switch fibers. I do get tired on middle distances and experience the fatigue of a typical middle-distance runner. In fact, I belive was it not for the biomechanical flaws, I might have become a miler. I ran 1000 m in 3:03.8 a month before turning 13.

I believe there are two reasons I succeed in the marathon - one, persistence - relatively few have enough, which lowers the standard, and two, you can get away with more biomechanical waste at slower speeds.