Females are four to six times more likely to tear their ACL (knee ligament) than males. There are a multitude of reasons why researchers believe this to be true. Examples of these reasons include: an imbalance in the strength of the quadriceps muscle (front of the leg) compared to the hamstring (back of the leg), a greater Q-angle (the angle at which the femur meets the tibia) which is due to females having a wider pelvis than males, and how females tend to land with knees pointed inward and with a straighter knee during tasks like running and jumping. While the female anatomy (Q-angle) cannot be changed, things such as bio-mechanics and quadriceps muscle strength are things that can be trained to decrease ACL injury. For more information, see the articles listed below.