Let's be realistic here. If you think that a knife attack will be similar to the controlled conditions in the following exercises, you are in for a deadly shock.
I am sorry to tell you this: don't be naive.
Even under controlled circumstances (with wooden knives, supervision, a non-threatening training environment, etc), you can get hurt if you're not careful. Even more so in a real knife attack situation.
I would personally never confront an aggressive person with a knife or a weapon... unless I have no other alternative, that is.
The following self defense techniques are only devised to help you build certain skills that you may use later on instinctively if the need arises.
But they're only basic techniques.
To have a real chance, you should practice more advanced knife attack self defense techniques in a safe environment... And they do not necessarely come from Karate, but from other fighting systems such as Kali, Ninjitsu (Ninjukai), JDK, and others.
If you're interested in exploring effective techniques against knife attacks, you should check out a set of DVDs called The Knife Defense Fundamentals, and Advanced Knife Defense (A new window will open). Both DVDs are sold either separately or together in a set.
In The Knife Defense Fundamentals (a new window will open), you learn how to:
In Advanced Knife Defense (a new window will open), you build on the basic techniques onto a new level, learning:
A person goes berserk and tries to attack you with a knife. He attempts to strike you from an overhead position.
This will throw him off stride.
Follow through with any of your Karate combinations, or even better, run away and find a safe place.
A maniac tries to knife you in the stomach. What can you do?
This will make him double up with pain.
With the same leg you thrust at your opponent's knee joint, throw him to the ground and disarm him.
This self defense techniques is for a situation where your opponent lounges a back handed knife attack from across his body.
Disarm him and strike at any nerve center.
Fourth Knife Attack Situation
And What if your opponent tries to hold you up with a knife?
More specifically, what do you do if he surprises you and holds the weapon against your stomach.
You could grab your opponent's wrist. But in a real life situation, you run the risk of your opponent pulling the knife towards him, and cutting your fingers, wrist, or hand.
Turn your body away from the knife and smash him in the Adam's apple.