What is the most common site for joint injuries due to aerobic exercise?

The answer is ankle. This is because aerobic exercises - such as jogging, biking - involve endurance training of the large muscles especially of the muscles below the waist. Due to the prolonged time of exercise, the ankle is prone to injury such as sprain and strains. Inward twist of the ankle is the most common and sometimes can be prevented by using compression garments on the ankle.