Final answer:
Hamstring strains are common in athletes who participate in activities requiring speed, such as jumping and vaulting, and can be very painful with symptoms like stiffness and bruising.
Step-by-step explanation:
Hamstring strains are indeed very common in jumping and vaulting, because these activities require the muscles to work very hard, leading to overstretching and possible injury. Therefore, the statement is True.
Muscle strains, including those of the hamstring, are characterized by the tearing of muscle fibers due to excessive stretching. Hamstring strains are particularly prevalent among track and field athletes such as sprinters, who experience them frequently due to their reliance on speed and power. These strains can present symptoms like pain, stiffness, and bruising. Moreover, a history of hamstring injuries increases an athlete's risk of re-injury.