It is simple physics. If a person weighs about the same as you, give or take 20 pounds, the best you can do with a kick is stop them from moving forward or cause injury. There is not enough energy in the mass of your foot to throw them across the room. Your foot would have to travel at mock speed to do that and you cannot generate that much speed. You might break a rib or two (theirs, not yours).
I know what you are thinking, Monte, a 45 caliber bullet will do it and it is very small. Yes, but it is high energy. All that energy is transferred to the victim as the bullet slows down. It is called
conservation of energy. You cannot do that with your foot. Screenwriters simply do not know or do not care; after all, it is fiction.
The other thing that bugs me is when the hero throws a pistol/knife/magazine into the air, kills three attackers, reads the Wall Street Journal, has a cup of coffee, and then catches the pistol/knife/magazine just before another attacker strikes. This is becoming a common scene much like the chase scenes-again, no imagination from the screenwriters. First, you would have to throw the object rather high. The higher the object is thrown, the faster it is when it comes back down. Try this; throw up a piece of popcorn as high as you want and catch it in your mouth. You can do
it. Now try it again, but this time look away for three seconds. Now try to catch the popcorn in your mouth. That sucker will strike you in the eye. You may want to wear safety goggles. The problem is that you must be able to see the popcorn to catch it. When you look away, you lose eye contact and when you look back, you cannot see it fast enough to catch it. Now attempt to do that with a
larger object. Please do not try a chainsaw. Not possible.