half of plastic foam makes such a huge difference. That foam is good at absorbing energy. The energy absorbed by the squishing foam is energy that did not go into moving earth (of course) nor did it go into breaking your shoulder (hopefully). The potential energy of your body three feet off the ground was turned into kinetic energy of movement, which was energy used to do the work of deforming the mat. An optimized punch can capitalize on this fact of the ground being a near-perfect solid mechanical boundary if this is the method you choose. The fact that the ground is a flat horizontal surface however and not a vertical one, means that the orientation of the ground is not ideal for throwing a horizontal punch. You do not have the luxury of driving your body off of a vertical wall most of the time, and if you could it would change the dynamics of a punch. People speak about having a structure in place during a punch and rooting the feet to the earth, and this is desirable in general depending on the type of punch being executed. There are challenges with this statement however, and details to examine. If the base is established, if a rigid body structure is in place to resist reaction force; then this must be done extremely quickly, immediately prior to or perhaps during the impact event. But then, how is work done when the punching force has ended before it begins? If you tense your body up and lock your appendages in order to establish a rigid frame, then you will by definition be using muscles to slow or stop your punch. So then what is the value of a base and of structure? The value (if it supports your punching method) is to capitalize on geometry. It’s free and doesn’t require effort on your part. Again it’s important to realize that you simply won’t have time to lock your entire body prior to the punch making contact with the target- and even if you could, it’s illogical because you would have slowed the punch and made your fist incapable of moving forward (things which severely detract from optimizing a punch). The reaction force event that the body reacts to involves partially resisting the reaction force with structure, and partially with muscularity, ligament tension, and the like. There is a fine balance between having a satisfactory structure in place, and being able to use your muscles, tendons, etc. to resist the rest of the energy directed back you. Structure and base have value in that if reaction force must be dealt with, then having solid structure and base at least allows you to optimize your effort in dealing with the reaction force.
Gravity Every person walking around is subject to the force of gravity at all times. If you jump off a tall building you’re subject to gravity even in free-fall. You’re experiencing weightlessness as you accelerate (onto the street). In a vacuum, without wind resistance, all objects fall at exactly the 20