Tendons are the fibrous connective tissues that connect muscles to bones. They allow limbs to move and help prevent muscle injury by absorbing some of the impact that muscles take when we run, jump, or do other movements. Tendons are made up of collagen fibers that are flexible, strong, and resistant to damage. The structure of a tendon is similar to a fiberoptic cable or a rope, with small collagen fibers arranged in bundles. These bundles reinforce the tendon and make it stronger. Tendons connect muscles to bones at two points: the musculotendinous junction (MTJ), where the tendon attaches to the muscle, and the osteotendinous junction (OTJ), where the tendon attaches to the bone.