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ACL-tear Prevention

Breathing deep, you try and take in what your coach is saying. The ref calls your team from the sideline. Sweat dripping, you jog out, still breathing hard. 

A whistle blows and it’s game on.

You make a move for the ball and feel a pop.  You find yourself on the ground, grasping your knee with both hands. The stands deflate. Your loved ones hold their breath, hoping you’ll stand, but you don’t.

The athletic training staff runs out, ask what happened, tug on your knee, and whisk you away to the sideline.

That’s when they break it to you: you’ve just torn your ACL.


This story is all too common. A routine move you’ve done a thousand times suddenly and unexpectedly ends in an ACL tear.

One of the worst parts?

It’s almost impossible see it coming.


Life After an ACL-tear

Surgery is guaranteed after tearing an ACL. And that’s just the start.

Recovery is a 9-12 month process. If you want to minimize the chances of a re-tear (which is significantly more likely if you’ve torn an ACL in the past), rehab should be closer to 12 months.

That’s a whole year you aren’t playing your sport. A quarter of your high school or college career, gone.

You aren’t playing, and you aren’t doing a whole lot of anything other than doctors visits and physical therapy multiple times per week. 

All this to try and get back to where you were before the injury. 

Imagine if you instead spent that year training and getting better—faster, stronger, more explosive—rather than working to get back to the athlete you once were.

An injury like this doesn’t only cost you a season, it might also cost you a starting job when you get back, or prevent you from making that big play, all because you couldn’t train to maximize your athletic potential. 

Not to mention the financial burden…surgery and 12 months worth of doctors and rehabilitation comes at a cost.

Sounds obvious, but….you’re much better off never tearing an ACL in the first place!

ACL-tear Prevention: Three Critical Factors

There are four key predictors for ACL-tears: strength and power, strength symmetry, and body control. 

Strength and power are critical for both athletic performance and injury prevention.

Strength refers to the most force you can produce. Think of it like your one rep-max: the most weight your body can move. It takes strength to control your legs during sport, and if you don’t have enough, you’re exposed to injury.

Power is how quickly you can summon your strength when you need it. Many athletic movements happen in a fraction of a second, and ACL tears tend to happen over a 0.6s period, so it’s important to be able to access your strength quickly when you need it. 

Strength and power symmetry refers to how similar your strength and power levels are between legs. Nobody is 100% the same on both sides, but if one of your legs is significantly stronger or more powerful than the other, your body compensates in ways that put you at increased risk for getting hurt.

To minimize the likelihood of injury, your legs should be less than 10% different from each other.

Body control is the most well known of these risk factors. Knees that cave in when you run, jump, and make cuts increase the likelihood of injury. 

Testing each of these factors gives you a clear idea of your strengths and weaknesses and highlights exactly what you need to work on to remove as much ACL-tear risk as possible.

What does the testing look like?

We assess each of the above categories directly to determine likelihood of an ACL-tear.With this knowledge, we create a training protocol that is specific to exactly what each individual athlete needs in order to minimize ACL-tear risk.

Strength and Power / Strength and Power Symmetry Testing

Each leg is analyzed individually to understand the maximum level of strength and power they produce. They are then compared to see how symmetrical they are.

Strength Assessment

Isokinetic dynamometry is the gold standard in measuring strength, which means it is the most accurate method available. This is how we measure strength.

Below is an example of test results:

The green arrows point at the maximum amount of strength (measured in torque) each quad was able to produce. The red number above the word “flexion” is the percent difference between sides.

Strength differences greater than 10% elevate ACL-tear risk. In this case, this athlete’s left quad was 35.4% stronger than his right! Because of this, he is much more likely to tear an ACL. To remove that risk, he should strengthen his right quad.

Power Assessment

Forward jump testing reveals how powerful each leg is. Remember that differences above 10% increase the likelihood of tearing an ACL. 

Note that jump distance can be compensated for, but power cannot. In other words, you may jump the same distance on both legs while having one leg significantly less powerful than the other. Jump distance alone is not the best measure, yet it is what most coaches and therapists rely on. 

We go straight to the source and measure power directly instead of only analyzing distance.

Check out the videos below for examples of a few of the hop tests we perform:

[embedyt] https://www.youtube.com/watch?v=0AQ-LuMetv8[/embedyt]


[embedyt] https://www.youtube.com/watch?v=aaEnXDhwuEI[/embedyt]


[embedyt] https://www.youtube.com/watch?v=IZFUb082BjM[/embedyt]


Vertical jump testing using the force plates tells exactly how much you use each leg during a vertical jump. You’ll notice in the video below that even though the jump looks perfectly normal, many of the featured athletes use one leg significantly more than the other, revealing an increased risk for tearing an ACL. 

[embedyt] https://www.youtube.com/watch?v=t7gS-sWYZQY[/embedyt]


Body Control

No matter how strong or powerful you are, if you don’t control your knees well you may still get hurt. That’s why in addition to strength and power, we look at how you actually control your knees in athletic movements.











The pictures above show knees that are caved in during athletic movement (jumping and planting). When the knee collapses like this, the ACL is under the most tension and is most likely to tear.

This is just one dangerous position that should be avoided to maximally protect the ACL.

We analyze lower body control from the foot to the hip to make sure every joint is doing what it should be to maximally protect the ACL.

What happens after testing?

One of the bests parts about our assessment is that each and every test is objective, based in data and research, and gives you a number score. It’s not us saying “well, we think this could be better…”

Instead, we’re armed with data that says “your left quad is 24.3% stronger than your right and you scored an 8 on the movement assessment, which puts you at increased risk for tearing your ACL.”

With this knowledge you know exactly what you need to work on to advance your athleticism and minimize the chances of getting hurt. We design a program that is tailor made individually for you that address the risks found in your assessment. After completing the program, you re-test to measure your progress and discover how best to continue from there. 

If you want to know the truth about how your body works, and if you want to prevent a devastating, life-changing injury, this ACL-tear risk assessment is for you. 

Ready to go?

If you’re ready to commit to your future and complete an assessment for yourself, fill out the form below and we’ll contact you soon to schedule!