Some Physics Applied to Contact Sports

Did you ever notice how a smaller guy somehow looks tougher than a bigger guy when they have impact in contact sports? Yes, it is all about heart and soul, but it is also pure physics. Let's look at Newton's Second Law of Motion, F = MA . F stands for the force of the impact and that is dictated by the Mass (size / weight) and the Acceleration (related to the speed at impact). So the size of the player is certainly a factor, but so is the speed / acceleration of the guy who is doing the hitting!

But there is even more "physics" than that when it comes to contact sports such as ice hockey and football, as examples. A player who is standing straight up with his feet together has a higher center of gravity, thus is more unstable. He is much easier to push out of the way or even knock over. You see it all the time in ice hockey. Yet a player who has his knees flexed, down in more of a ready position, with his feet spread apart is MUCH harder to push out of the way or knock over. The reason is that his center of gravity is lower, and with his feet spread apart he is much more able to absorb and withstand the shock of the impact, it is distributed across a much wider area, it is not as concentrated.

There is even more "physics" involved with impact / hitting with contact sports. In ice hockey it is "checking", in football it may be in blocking or even tackling. When a player comes in low he keeps his center of gravity lower, thus he will have an advantage of being more stable when contact is made. Further he can compound the force of his impact by not only making the force component horizontal, but by raising up upon impact, kind of uncoiling, he adds another force component to his hit, making the total force upon impact much greater.