EngineeredTheology

Like most people, I have pains when I run. Knee pain, shin splints, hip pain, etc. I don’t really mind running, but I wonder if it really is supposed to be so painful. Weren’t we meant to run?

It is obvious we were born with the ability to run, but I wonder if our current shoe technology is forcing us to run in ways that are not biomechanically correct.

If you were to take a look at any modern running shoe, you would see a very thick heal and much less at the toe. The thought when this design was created was that this would enable the runner to always be running “downhill”. This thick padding started allowing heaver and heavier heal strikes when running. What this means is that you can run impacting the heal first, then rolling back to the toes. This is extremely uncomfortable way to run if you don’t have any shoes on. As a matter of comparison, if you take a quick run around the room barefoot, you’ll find you can’t reasonably land heal first every time.

This heavy heal strike, even with the significant shoe padding is extremely tough on the joints. When a runner reaches forward with their front foot and lands, there are impact forces that are created. With the quick vector diagram above, there is a force pointed down (to counteract gravity) and a resultant force pointed in the opposite direction of motion (i.e. a reaching heal strike will slow down your forward momentum).

When the force is followed up through the leg, it goes directly to the knee joint (as often the leg is straight). There is no dampening available, so the knee joint (specifically the cartilage) will see all the impact force. This then flows up into the hip joint. It is not a dramatic leap to hypothesise that this could create knee pain.

The main next question is, is there a different way to run? When I watch my kids run, the do not know to land with their heal first. They run (both barefoot and with shoes) on their “toes” – on the ball of their foot to the midfoot. This is the same way you will find yourself forced to run if you do the little experiment running barefoot around the room.

Running on the midfoot (think of landing on the back part of the balls of your feet – the heal can still touch, but it is not taking the impact forces) can be a natural way to run, but may have been un-learned by years of wearing “comfy” shoes. You will naturally find youself no longer reaching your front leg in front of you and landing with your foot directly under your body (if not even a little behind).

This has two main effects.
1. There is no longer a force opposing your momentum (it should take less energy to keep moving forward)
2. The knee will be bent

While the first effect is nice, it is the second that can help with joint pain. First, landing on the balls of your feet, there are dampening forces (think shock absorbers). When landing on the midfoot, the impact force goes not through your tibia, but from the achillies tendon to the calf muscle. This then works its way up to the quads and hamstring muscles. Since muscles are meant to expand and contract, they are much more able to handle these types of forces than the cartilage in joints. The hip and knee joints are active participants, but will not be required to take direct compressive forces.

This is the way I have begun to run. Of course, even this is not perfect. I have replaced knee pain for significant muscle and tendon pain. On the onset, the pain was far more severe. I suspect this is due to significantly higher forces being required of muscles that have never been required to handle them. After a month they are all but gone away and I have absolutely no hip or ankle pain and significantly less knee pain than before.

The interesting thing is that I have been able to run much farther and much faster than ever before.