Saturday, January 8, 2011
Ryan Hall Carries His Arms Too Low
Compare Ryan's arm carriage in this video to the one below of his American record half marathon performance in 2007. I see a clear difference in the angle at the elbow and his hands are now consistently swinging below hip level. Unfortunately, the quality of the American record video isn't the greatest, and the soundtrack is even worse, but you can clearly see that his elbows are breaking 90 degrees and his hands are consistently held higher.
I believe a lower arm carriage can make a significant difference in energy cost over 26 miles. According to Coach Roy Benson,
To see how tightening the angle at your elbow will make your arms swing through their range of motion quicker, picture a pendulum like the one in a grandfather clock as it swings back and forth with a counterweight attached. The length of the arc of the pendulum swing will depend on the center of gravity of the pendulum, and that’s determined by the position of the counterweight. The lower the center of gravity, the longer the arc and hence the more time the clock takes to record each swing. Thus, If the clock is too slow, by raising the counterweight, you’ll raise the center of gravity and thus shorten the arc of the swing back and forth. In short, the clock speeds up and runs faster. -runningtimes.com
I know about this because I have the same bad habit.
In case you are not familiar with Ryan Hall, check out his bio at wikipedia.