Your head is a heavy weight at the end of the longest lever of the human body – learn to use it effectively: The average human head weighs just over ten pounds (around 4.5kg) and is positioned at the end of the longest lever in the human body – the spine. As such it can be used to supply a surprising amount of weight in directions you need if used correctly. Look how gordon ryan uses head position to nullify what could be a dangerous underhook. Learning to use the PLACEMENT of your own head and the DISPLACEMENT of your opponents head is a big part of what it means to maximize the nature of the human body to advantage. Ten pounds may not seem like much, but when it's connected to a long lever it can get very heavy indeed as that lever gets lowered over your target. Think about connecting a ten pound dumbbell to a good sized stick and then holding the other end of the stick in your hand. As long as you keep the stick vertical it is quite manageable – but as soon as you lower the weighted end of that stick it quickly becomes a very heavy burden indeed! Learn to use your head in similar ways and you can become a burden to even a very strong opponent in ways that can point you towards victory
