Found on RunnersWorld.com and written by Alex Hutchinson
Is it really possible to land right under your center of gravity?
Most of the debate about running form focuses on how your feet hit the ground (i.e. heel, forefoot). But there’s another question worth thinking about, which is where your foot touches down. The conventional advice you often hear is that you should avoid having your foot land too far in front of your body, because this will effectively cause you to brake and waste energy. But how far is “too far?”
I was reminded of this question after I blogged a few weeks ago about a study claiming that, if you adjust your stride just right, you can use the force of gravity to propel you forward while running. When people make this sort of claim, it’s often accompanied by the advice that you need to have your foot land directly underneath your center of gravity.
In the ensuing discussion, Brian Hanley, a researcher at Leeds Beckett University in Britain, mentioned a paper from a few years ago where he and his colleagues videotaped 20 competitors during the English 5K road racing championships and performed 3-D gait analysis at three points during the race (950 meters, 2400 meters, and 3850 meters).
The runners were remarkably consistent with foot placement, landing about 33 centimeters (13 inches) ahead of their center of gravity. That stayed roughly the same throughout the race, even though the runners were slowing and reducing both their stride length and cadence: the three measurements for the men were 33, 33, and 34 centimeters; the three measurements for the women were 33, 31 and 33 centimeters, on average. This is despite the fact that the men had a significantly longer stride length by about eight inches (~185 centimeters compared to ~165 centimeters).
So what does this mean? These were elite or near-elite runners, but of course there’s no guarantee they were running optimally. That said, the results fit with what others have previously observed. Way back in 2010, Pete Larson of Runblogger wrote a great post debunking the notion that your foot should land directly underneath your body, pointing out that even Pose and Chi gurus who advocate landing under your body actually land in front of the body when you look carefully at video of them running.
A caveat that Pete noted: sometimes a piece of advice can be useful even if it’s not “true.” Telling people to try to land under their body might help them correct overstriding, even if they don’t succeed in actually doing it. (You could make a similar argument about suggesting that you should take 180 steps per minute, advice based on bad or non-existent science that might nonetheless help some people.)
The next logical question is: Is it even possible to land with your foot directly under your center of gravity without falling flat on your face? Pete and others argue that it probably isn’t. And here’s my appeal for help: I remember seeming a journal paper within the last year or two that made this argument on theoretical grounds. I can’t remember whether it was for walking or running—and I can’t remember anything else about the paper, which means I can’t find it. If anyone knows the paper I’m talking about, please let me know!