Push or Pull?

Push or Pull?

 

When stepping forward using zenkutsudachi (front stance, see August 2000 article), should we be pushing off the back leg? Or should we be pulling from the front leg? Or should we be doing a combination of both? Some people have some very strong opinions on this push/pull relationship, while others have not thought about it much, if at all.

Let’s try some experiments to isolate the push and pull and look at their relationship.

Facing a wall with your front foot about 12-18 inches from the wall, push against the wall with your arms while in front stance and lift the front leg (this position also used in article on alignment, from March 1998). Notice that the forward thrust is essentially the same without the use of the front leg. The primary use of the front leg seems to be that of brake. Now, lift the back leg and push. There is probably not much forward thrust, if anything. In fact, you may find yourself falling back unless the weight of the body is shifted forward. This indicates that, at least in a stationary front stance, the back leg’s forward drive is important and may be used as a major force for propulsion forward during stepping as well.

Next, stand away from the wall in front stance and, lifting the back foot slightly for a moment, move your weight forward and step to the front. Notice how much you “pull” with the front leg when stepping. (In precise biomechanics terms, “pull” is not entirely accurate, but is a good conceptual term.) If you practice this for a while, you can see that active involvement of the muscles of the front leg can provide a definite improvement in the speed of forward movement of the body during stepping.

Considering the above two experiments, it seems that there must be some pushing and some pulling involved in the forward stepping motion during front stance movements, or at least there should be during most situations. The question still remains, however, as to how much of each is involved.

One of the primary determining factors in figuring out the relationship between pushing and pulling is the distribution of weight forward/back. Try the second experiment again if you have any doubts. Try it with the weight further back that usual and then further forward and see which seems to utilize more of the pull necessary for this movement.

So, the pull seems to be a larger contributing factor the further forward the weight is distributed toward the front, right? Well, not necessarily. . . There comes a time when the use of the front leg is not as a “pull” as much as it is a “push.”

Consider the sprinter. While a marathon runner starts from a standing position, a short-distance runner really relies on the initial thrust off the starting blocks. Not just low to the ground, the sprinter also starts with his feet on blocks against which he pushes forward to gain initial momentum forward. While the use of both legs is employed, the role of the front leg is probably more of a push than a pull. That this is more of a “push” than a “pull” is partially related to the fact that the sprinter has blocks off of which to push. In comparison, the karateka has just the floor off of which to push, which is not at such an advantageous angle in relation to the direction of movement. In addition, we should consider that the sprinter starts with the weight situated relatively far forward, more so than many karateka’s front stances.

So, the further forward the weight is situated, generally speaking, the more of a part the front foot plays in moving the body forward. While the weight is behind the front foot, this can be considered a “pull.” After the weight passes in front of the front foot (soon to become the back foot), the function shifts to that of “push.” The push off the back leg (cannot be considered a “pull” any way you look at it while stepping forward) may be significant-actually likely the most significant part- but lasts for only a brief moment before the front leg takes over.

Also affecting the contribution of the back leg’s push is the amount of flexion in the leg. If the back leg is perfectly straight, very little force can be applied by that leg. When straight, that leg depends solely on the muscles of the ankle and foot for forward thrust unless that leg is momentarily bent before the forward movement, which of course takes valuable time. It might also give away the intention of movement to the opponent and have other detrimental effects.

This relationship of push/pull depending on weight distribution applies to other stances and stepping types as well. When stepping back in front stance, the front leg pushes back to a very high degree, while the back leg “pulls,” at least at the outset of the movement. When stepping forward in back stance (also see article on kokutsudachi), the back leg definitely provides the majority of forward thrust. While stepping back in back stance, the back leg pulls and the front leg’s push is minimal, at least when performed according to proper Shotokan basic form.

In summary, both pushing and pulling forces occur while stepping, but sometimes significantly more of one than the other. Furthermore, what we think we are doing and what we are actually doing may differ greatly. I would hope that everyone will want to individually examine how the push and pull of the legs are utilized (or should be utilized) when stepping and how this relationship is affected by weight distribution and leg flexion. By better understanding these points, you should be able to make better use of the various forces involved while training.

Copyright © 2022, Jon Keeling (originally published December 2001)