I wanted to write for some time about the feeling of running downhill... on flat surface ! When you run downhill, you can easily feel the acceleration due to the combination of gravity and a foot pose very close to the runner's center of mass. As a matter of fact, on flat roads, you can feel the same phenomenon. Here's a quick illustration by looking at the very peculiar running style of the young amateur Japanese marathoner phenomenom, Yuki Kawauchi (which I already spoke about in this blog). These pictures were taken during the marathon of Fukuoka in 2011. They are particularly interesting because we can compare the style of Yuki Kawauchi and the one of his competitors running at the same speed.
Three key points stand out:
- A pose of his foot very close to his center of mass by Kawauchi (who wears a black running short):
- The body slope of Kawauchi: it shows how he is really bent forward with his whole body ; the other rider has an almost identical angle (about 68 °) from the middle line of his neck to his lateral malleolus) but we see how his back is more bent over compared to the one of Kawauchi. His buttocks are much closer to the red line than the ones of his competitor. This makes the weight distribution quite different.
Even at the end of the push off phase, Kawauchi is still bending a lot forward. His shoulder line is really in front of his waist. Look how his chin is in front of his whole body. Other runners tend to keep their chin more or less above their chest during that phase.
- Arms' swing: Kawauchi moves his arms very little and carries them pretty low, just like when running downhill: on downhills, there is no need to pull the arms and the arms are primarily used to keep his balance.
Now you can see the foot path difference between the two runners up on the following sequence:
quite similar starting position of the front leg of the two riders:
Kawauchi (back) gives the impression of going faster forward with his foot:
Kawauchi (second level) opens slightly less his knee:
Kawauchi (second level) brings his foot back earlier:
Kawauchi hits the ground closer to his center of mass and his foot pose is flater than the one of the other runner (in red).
I found amazing that Kawauchi is able to keep this type of running form all along the marathon and especially in the last few miles of the race. What an amazing stamina !
Happy Feet Running Light !
NOTE: The pose of the foot and the forward slope are further detailed and explained in my book LIGHT RUNNING FEET.
NOTE TO READERS: The pictures in my posts are displayed for educational purpose and are not scientific pieces of evidence. These illustrations are there primarily to provide a better explanation of my articles and make the reader think.