by **Rick Wilson** » Tue Sep 21, 1999 6:43 am

Gary S:

Certainly sounds like you have everything working well. Very well connected strikes often feel less powerful than poorly connected ones. This is because poorly connected strikes have force dissipating back into unaligned parts of our bodies and we "feel" that force. Well aligned strikes dissipate the force into the ground and we "feel" them less.

Pardon me for not knowing your background, but do you get a chance to hit well conditioned people? A punching bag that gives verbal feedback is one of the best tools for judging your striking strength.

Yes, there are physical limitations that you can reach. As Gary K said you are limited to the mass that you have, so once you are striking with every bit of it then that is that. However, there are other elements that come into play: striking through, and I agree with who ever posted about mental aspects -- intent.

Kevin:

An engineer friend and training partner does not exactly have the acceleration squared but he did write me a very long explaination dealing with force and kinetic energy that goes into the force equation in great detail:

To Rick W.

A couple of points on the question posed. I think he is miss interpreting the force (F = MA) equation. It isn't how fast that you accelerate "to" but how much velocity you de accelerate into the target and the time it takes to do this. Acceleration is the rate of change of velocity with respect to time. Therefore in our application, we can simplify to Vd the velocity dissipated into the target and Td the time it takes.

Therefore, the equation can now be represented by F = MVd/ Td

I look at the equation F = MA as the potential force that could be developed and the equation F = MVd/ Td as the actual. For example, if your punch was accelerated to 1000 miles per hour and you only dissipate 10 miles per hour into a target because you pulled the punch. The 10 miles per hour is the only number of concern to the target. Note: 990 miles per hour is the velocity that was pulled and that force is absorbed by the punchers body. The above equation applies. It is important to learn to punch through a target. That's why people hurt their shoulder when they punch air if they hold their shoulder rigid as some people are known to do in Sanchin. All the force is dissipated into their shoulder.

What makes increasing the dissipating velocity doubly attractive is that by doubling this velocity you increase your punching force by a factor of 4. This is because you decrease the time by 50 percent in most cases. Using simple numbers to illustrate this point.

F = M x Vd/ Td where Vd = 4 miles per hour and Td = 4 sec

F = M x 4/4 = 1 M

if we double the velocity by making Vd = 8 miles per hour and the time reduces to Td = 2 sec

F = M x 8/ 2 = 4 M

Kinetic energy is another tool to use to understand the effect of a punch. Kinetic energy is a measure of the motion of a body and is a measure of the capacity of a body for doing work because of its motion. To create kinetic energy a force has to be applied to a body and displace it in space. This application of force (F) and displacement (D) is measured as "Work". Work is a technical term that is defined as the measure of the effectiveness of a force in moving a body thru a distance (Work = F x D). It is measured in foot pounds. If you have 550 of them you have 1 horsepower. The amount of work applied to a body determines its kinetic energy. One's punch can be considered a moving body and thus has kinetic energy. Therefore a force had to have been applied to the mass (body) of the punch to cause it to move. Until he hits the target, Kinetic energy is the capacity of the punch to do" Work". Therefore, when the punch hits the target, the kinetic energy is converted into a force which tries the target in space. This "Work" gives the target kinetic energy. Again, what is important is not the velocity of the punch but the velocity that is dissipated or applied to the target. What is interesting, is that you need to use the mass (Mt) of the target hit and its change of velocity (Vt) to measure the work done. The punch's mass (M), the velocity dissipated (Vd) and the time to dissipate (Td) are used to determine the force applied. So when he hits the target

Work = 1/2 Mt(Vt)(Vt) = FD

where F = MVd/ Td

As always, I look for what is the objective. I believe the objective is to determine how to develop a more effective strike and to be able to explain to one's students the importance of what we are teaching. That is why I like the force equation so much. It has all the components that do that. Three simple terms, mass, velocity and time. Kinetic energy ignores time. Time is critical if you consider that it takes longer to dissipate a punch in belly fat than on your chest. Therefore with the same velocity and mass you will generate more force hitting the chest than belly. This leads to having a strong weapon. It doesn't do much good to punch the chest if you break your wrist. This bring to mind Newton's law of motion that states " for every action there is an equal and opposite action". This helps us understand the importance of being properly anchored (good stance) when we hit somebody. As you have probably observed over the years, I can get lost exploring the implications of this equation.

by Rick Bottomley

Rick W.