ACL Risk Factors and Preventative Training Tips

By Vanessa Ramirez, MS, ATC

There are many different types of risk factors for anterior cruciate ligament (ACL) injury. Some risk factors include, but are not limited to, body mass index, weak hip musculature, and weak abdominal or core stability. Higher-than-average body mass index is a risk factor for ACL injury. Individuals who are overweight tend to possess more fat in the abdominal region, and they may be less capable of controlling their trunk movement compared to individuals who are not overweight. This inability to control the trunk may lead to trouble with balance. Balance and abdominal stability are important factors for physical movement, especially athletic movement. It is important to have a strong core because this allows individuals to produce and absorb force in a manner that reduces risk of injury. Individuals who possess decreased hip strength tend to have their knees "cave in" or collapse inward when they run and/or jump. This type of movement places the ACL in a vulnerable position and increases the risk of ACL injury.

As for some preventative training tips, individuals can perform exercises to improve flexibility, agility, and strength. Individuals can properly warm-up before participating in physical activity by jogging, performing dynamic stretches, and preparing the body for movement. With proper flexibility, individuals are able to move their body through the proper range of motion and avoid vulnerable positions that may increase risk of injury. Individuals can look to stretch their hip, thigh, hamstring, and calf muscles. Some examples of dynamic stretches include alternating walking hamstring “scoop” stretch, alternating walking lunge hip flexor stretch, and alternating walking "figure 4" stretch. Ladder drills are great exercises to improve agility. As for core and hip strength, individuals can perform bodyweight squats, with or without a resistance band above the knees, and lateral band walks, with or without a resistance band above their knees. They can also perform alternating walking lunges and hip bridges. These exercises aim to increase the strength of both the hip and core muscles. These exercises do not have to be performed every day. They can be performed a few times a week before practices or games and require little to no equipment.