I have found two different explanations of the Chinese symbol for strength.
The first is that the character is the drawing of a flexed arm. A powerful dynamic representation of physical strength.
Actually one of the ancient form of the character, the Small Seal - that you can find below - could represent a tendon, that connects the muscle to the bone, supporting this interpretation.
Others instead see the character as a drawing of a plough. Using a plough actually requires a lot of strength ...
I have found many websites that show 力量 as the (double) character for strength - that is true but 力量 (li4liang4) means more physical strength, force or, also, implies a measurement of the strength (you will use 力量 to say how many horse power you car has, for example).
力 (li4) alone instead relates to a more general and abstract concept of strength.
Please enjoy below 14 different pictures of the Chinese character for strength that can be downloaded and used as you like (including tattoos, t-shirt, decorations ...)
|Traditional Chinese Character for Strength|