ACL Injury Prevention

The anterior cruciate ligament, more commonly known as the ACL, is one of four important ligaments that provide stability to the knee joint and prevent your knee from moving in ways that would make it hard to use your legs. ACL injuries affect about 250,000 people annually in the United States alone. Here at Incontrera Strength and Conditioning (ISC) we make very clear that one of our main goals is injury prevention, and protecting the knee in particular is a top priority. This week's blog will review methods that we use to help protect the knees. It’s important to keep in mind that, sometimes these injuries are unavoidable. There are things we can do to help prevent a non-contact injury but there is no guarantee that injuries won’t still happen.

The ACL is a stabilizing ligament at the front of the knee, right behind your kneecap. It’s main job is to prevent the knee from straightening too far. However, it’s not a muscle, so it can’t be trained or strengthened on its own. This means that as your training intensity increases, the limits of your ACL remain the same. In order to prevent the ACL from absorbing excessive forces which would cause a tear, we need to make sure that the rest of the body is doing it’s part in keeping the knee stabilized under pressure. You never want your ACL picking up the slack when things get tough.

The main things we can do to protect the ACL from absorbing excessive force is to first and foremost, make sure we have good flexibility and range of motions through all of our joints. Tight hamstrings or hips are a recipe for disaster. From there we need to learn how to decelerate in a sprint and land from a jump,  improve the base of support in the feet and ankles, and increase strength and power in the glutes and quads to maintain good knee control.

Learning how to sprint or accelerate without learning how to decelerate is like teaching a pilot how to take off but not land. The majority of non-contact ACL injuries come from someone trying to change direction but putting themselves in a bad position while they do it. When we do speed training at ISC, the first thing we do is focus on depth jumps to learn how to absorb force, and then how to slow down and stop in order to change direction and accelerate again. We want to make sure you don’t land or stop with straight legs. We want to absorb that force by bending our legs, keeping a nice center of gravity and your knees inline with your toes to protect your knee and quickly move in another direction from your landing or stopping position. It seems tedious or boring when we practice it, but these little fixes make a big difference and the more we practice—the more we perfect our technique.

We can teach deceleration and landing techniques all day, but if we are not strong in the surrounding areas of the knee, then all that practice is wasted.. The foot/ankle, knee, and hips are all connected and if one is weak or injured, then the other joints will have to pick up the slack, likely having to do more than it can handle. This is how injuries occur.

With that being said, let's begin with the feet. Strong feet equal a strong foundation. It’s weird to say but feet are actually one of the most overlooked aspects of training. One way of strengthening the feet is an exercise referred to as, “bridge the gap.” This is  you have two plates a few inches apart and you stand with one foot bridging them together. Your heel is on the back plate and the balls of your feet are on the front. This is great for strengthening the arch of your foot which is important for more reasons than just the ACL. We also like to do variations of bounding—which is where you jump in different directions and land on one foot and balance for a few seconds. It helps reinforce the landing techniques and balancing by landing on one foot. This particular exercise also helps strengthen all of the stabilizing muscles in the ankle and foot, as well as create an equilibrium between the hamstrings and quadriceps. 

On the other side of the knee, you have your hips to consider. In order to take care of your hips, you need to strengthen your glutes—which are the hips main stabilizers and help externally rotate them. We want to learn how to activate and create power from the glutes. If your glues are not “activated” then your hips can internally rotate, and cause the knees to bend inwards, placing more stress on the ACL. At ISC, we activate the glutes with different warm-ups using bands or hip extension variations. To strengthen and create power from our glues, we do exercises like squat, hip thrust, and deadlift variations.

The final component we need to focus on is the quadriceps. Quadricep strength dictates how strongly you can lock your knee in extension. Having good quadricep strength helps to prevent jerking actions at the knee, caused by landing or pivoting movements, which can be associated with ACL injury. Again, squat variations are very good for the quads but we also like to implement variations of terminal knee extensions (TKE’s). TKE’s are technically when you just slightly hyperextend your knee or flex your quad, but my personal favorite variation is a banded TKE.  You do these by attaching a band to something that won’t move and stepping inside of it so it’s wrapped around the back of your leg, then you step back until there’s tension in the band and then straighten your leg completely. This is a great way to strengthen your quads while not putting a lot of stress on the actual knee joint. It’s also great for ACL injury prevention and I still do it on squat days to help eliminate that post-workout pain.

As stated earlier, these are just steps we take to try to prevent ACL injury, it is not a guarantee and there are more ways to protect yourself than what I’ve written here. Regardless of where you train or how often, you must give yourself a good warm-up to activate all the important muscles and effectively stretch them.. Practice good technique and be strict about it, so that in competition it becomes second nature. Finally, be consistent with your training and always strive to do a little bit better than the last time!

- Coach Tom