This short video lesson explains the principle of fulcrum, lever and base, demonstrated on a body. It is for martial artists and self-defence students who want their locks to work, and who want to move an opponent in the direction they choose.

Once you understand this principle, you can start to take your locks to new levels. The same principle can be used to move your opponent wherever you want them to go. Take the time to learn it well.

The Principle in Plain Terms

Every lock and every lever has three parts:

  • The fulcrum, the point that the movement turns around
  • The lever, the part you move, such as the forearm or the whole arm
  • The base, the stable part that stops everything moving together

If any of the three is missing, the lock fails. Without a fulcrum, there is nothing to turn around. Without a base, the whole body just moves with you and the pressure goes nowhere. Without a long enough lever, you need far more strength.

Why Locks Fail

Most failed locks are not a strength problem. They are a fulcrum, lever and base problem. People grab the wrist and twist, with no fixed point for the joint to turn around. The other person simply turns with the twist, and the lock disappears.

Put a fulcrum in the right place, keep the base fixed, and use a long lever, and the same lock needs very little effort. That is why a smaller person can control a bigger one when they understand the mechanics.

Moving an Opponent

The same idea works on the whole body. If you fix one part of someone, such as a foot, a knee or a shoulder, and move another part, the body has to go where you send it. That is how you take balance and set up takedowns without wrestling for them. It also makes follow-up strikes far easier, because a person who is off balance cannot defend properly.

How to Practise Safely

Locks put real stress on joints, so train them slowly with a cooperative partner. Agree a tap before you start and release the instant your partner taps. Find the fulcrum first, then the base, then apply the lever gradually. Speed comes much later. In a real situation, use only reasonable force, enough to control the threat or get away, and nothing more.

Take It Further

Locks become far easier when you combine leverage with pressure points and balance, which I teach in the Pressure Point Fighting Course. For security and door staff, the PPDT Online Course applies these control principles to your work.