A tendon is a fibrous tissue that connects muscle to bone, other muscles or other structures, such as the eyeball. A tendon is responsible for moving the bone or structure connected to it.
An example of a major tendon is the Achilles tendon. This tendon connects the calf muscle of the leg to the heel bone.
Tendons withstand an enormous amount of force, but they can sustain damage if overused. Tendinosis is a medical term for the breaking down of tendons over time. The blood circulation in the tendon decreases, causing pain. Tendon degeneration occurs when the collagen that the tendon is made of weakens over time.