Anyone can get tendonitis, but adults over age 40 are most susceptible. As you age, the tendons tolerate less stress, are less elastic, and are easier to tear.
Athletes are also more prone to developing tendonitis. You may have heard of some common sports injuries involving the tendons, such as jumper’s knee, tennis elbow, golfer’s elbow, and pitcher’s shoulder. These sports injuries occur from overuse, and as a result the tendons become inflamed.