Sunday, March 14, 2010

The Problems with Heel Landing

Many people come to Pose Running in an effort to reap the benefits of a forefoot strike. So I'm going to cover heel striking vs. forefoot striking in this post.

First a word of warning: 
There is more to adopting a forefoot landing than pointing one's foot down as one lands. Adopting a forefoot landing must usually be done as part of a more comprehensive change in running technique. So I do not want to encourage people, who currently heel strike, to start forcing a forefoot landing while using their current technique. This could lead to injury. In other words, don't selectively try to apply elements of Pose Running Technique to your current technique. Every element of Pose Running Technique is closely related to the all of the other elements, so take the time to learn it correctly!

Background:
Prior to the invention of the modern running shoe circa 1972, running coaches almost universally advised runners to adopt a forefoot landing. The reasons were very practical and based on experience. Runners who landed on their heels usually suffered more injuries and would have very short running careers. Today there are still areas in the world were people run and train without modern footwear, and these people almost always adopt a forefoot landing. 

Unfortunately, the vast majority of runners, who have learned to run in modern footwear, land on their heels, and in less than four decades, it has now become accepted as faith among most distance runners that running shoes are necessary for running, and that landing on one's heels is normal. The fact that people were running just fine prior to 1972 never really seems to occur to most people. Some people are so attached to this faith, they become extremely hostile  or dismissive to any suggestion that it might be wrong.

Why is heel landing a bad practice? 
There are three basic reasons heel landing is a bad idea, although they are all closely related.
  1. It is mechanically unsound, causing the runner to both break in mid-stride.
  2. It cuts the falling phase of the stride short, thus preventing the runner from moving forward as far with each stride.
  3. It causes the runner to use unnecessary muscular effort to regain the Pose position.

It cuts the falling phase of the stride short:
The reason people land on their heels is that they are dropping their leading leg out of the Pose position too soon. Remember from my previous posts on the fall, that the runner should hold the Pose position as long as possible. When a runner drops his or her leg too soon, he is not able to fall forward as far as he can when maintaining the Pose. Look at the difference between the Pose Runner and the typical runner.


Pose Runner

Notice that the runner remains in the pose while falling (the second figure to the right) right up to the transition.






Typical Runner

Notice that the runner drops his lead leg prior to the transition (the second figure to the right), forcing his foot to land before his hips have fallen forward as far forward if he maintained the Pose.


It is mechanically unsound:
I'm going try to explain this using analogies and examples rather than Newtonian physics, force vectors, and blah blah blah. In the future, I hope to a do a more technical post on this subject, but for now I won't subject the few readers of this blog to such "captivating" material. However, if you, the reader, would like a more technical post on this subject sooner rather than later, please let me know and I'll get right on it.

The pole vaulter example - When a pole vaulter wishes to change the energy he or she is using to run forward into upward movement, how is this accomplished? The vaulter does this by dropping the pole that he or she is carrying directly in front of his or her path of motion and ahead of his or her general center of mass (or GCM).

What happens next? The pole absorbs the energy generated from the vaulter's run by bending, and the vaulter immediately and dramatically slows down. Of course pole vaulters do this intentionally so they can use the energy absorbed by the pole to help lift them vertically into the air.

So what does this have to with running? When typical runners land on their heels they are almost always landing in front of their GMC, and essentially doing exactly the same thing as the pole vaulter. The only difference is that most runners do not have legs as long as a pole vaulter's pole, so the effect is less dramatic. Runners generally are not attempting to change their horizontal motion into vertical motion, but that is exactly what they end up accomplishing by landing on their heel out in front of their bodies.



The bully example - Although I was never subjected to bullying when I was in school, I did on occasion witness what happens when a one of the local bullies would push someone from behind. When someone is pushed from behind, what do they do to prevent themselves from falling forward? They throw their leg out in front of themselves to break their forward movement. Remember that when running, forward movement is accomplished by falling forward, and when a runner puts his or her leg in front of his or her body, he or she is breaking the forward movement of the body, just like some getting suddenly pushed from behind.

The wheel analogy - Why aren't wheels shaped like triangles? It's because triangles don't role easily. Their angles create flat sides that are very stable and resist rolling. Conversely, wheels are shaped like circles because they have no flat edges to create a stable base or platform, and thus do no easily resist movement.

When a Pose Runner lands his leg becomes like the spoke of a wheel. There is no resistance to falling.
When a typical runner lands he must overcome the resistance of a stabilizing angles that resist his forward motion.


It causes the runner to use unnecessary muscular effort to regain the Pose position:

As I mentioned above, when a runner lands in front of their GMC, he or she must break because there is a lot force moving forward into the leg. If the runner did not attempt break, the leg would quickly become injured. This is different from the Pose runner who lands in a position that allows all of the forward force to be applied directly to the next fall rather than into the leg.

When a runner breaks, he or she does this by contacting his or her thigh muscles with an eccentric muscular contraction, allowing the leg to collapse slightly in order to absorb the energy. Again, this is very similar to the pole vaulter's pole.  After the leg collapses, he or she must regain that height by pushing up with the leg. The result is that the runner waist energy unnecessarily with each step. This effect is often easy to see. Runners, who appear to be bobbing up and down excessively, are probably doing so because they are losing and regaining a lot of height with each step.

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