Strength is the most important element in martial arts. It was said that 3 attributes (Guts, Strength and Technique) determine the outcome of a fight. Without guts, you should not be in a fight. Without strength, it is like fighting like a child. An eight old kid which knows all the right moves cannot hurt you. However strength is one of the easiest skill to train especially in modern times. There are so many gyms around with various equipment that train every single muscle group that you have. Martial arts normally focus on the triceps and chest muscles. Some of the traditional strength training exercises that need no equipment is shown below.
This is the most commonly done exercise which is rather easy. Traditionally, it is
performed at very high number of repetitions (eg 81,100). There are a lot of variations such as close grip,
wide grip. For more difficulty you can place legs on a higher object to do incline push ups.
It can also be done with knuckles or fingers. For finger pushups, start training with
5 fingers, 3 fingers, then two fingers or even one finger (normally the thumb). However,
there are two form of finger push ups, straight fingers or curved fingers. The image shows
me doing straight 2 fingers push ups. Straight finger pushups are very much easier to do than
curved finger pushups. Some people also call curved fingers push ups as vertical finger
push ups (The finger tips are almost vertical to the ground).

Open up the legs for better balance. Place unused arm behind your back and do
push ups with one arm. You can do with palm, knuckles or fingers as before. Image shows
one arm knuckle push ups

Stand on your hands and do push ups. To ease worries on balancing,
lean feet against a wall. If it is too easy, perform the handstand on a table
so that you flex your arms more.
Perform FULL squat using one leg only while keeping the idle leg straight and parallel to the ground
One of the best know set of traditional isometrics exercises is from the book of muscle change from Shaolin.
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