Preventing Knee Injuries: Checking Your Risk for ACL Injury

Overcome ACL Risks and Boost Outdoor Resilience

As outdoor enthusiasts, injury is one of the hardest things we deal with. Being sidelined and missing out on a season of your favorite activity is heartbreaking! We would know: as a teenager, I tore both ACLs within a couple of months of each other! Those injuries were devastating at the time, and took a lot of work to come back from. 

Among skiers, ACL tears are the most common knee injury. And they are especially common among women.  

The good news is we have tools we can use to understand how likely we are to injure our knees. Armed with that knowledge, we can make smart decisions about how to train to reduce our risk. Of course, there's no way to guarantee remaining injury-free. Life happens! But we can stack the deck in our favor, and that’s powerful.

What follows is an assessment of your personal ACL injury risk. Knowing what your weak points are can be scary, but with that information, we’ll be able to develop a plan for what to do about it! (Spoiler alert: Ski Babes is designed to address all of these issues of weakness & knee vulnerability!) 

Checking Your Personal Risk for ACL Injury

The classic phrase very much applies here: every body is different. Understanding exactly where and how your body does or doesn’t carry injury risk on your knees is empowering! We have a whole slew of easy tests you can do at home to help you target exactly what kind of training you need to reduce the odds of getting injured.

Let’s go through each risk factor for knee injury – plus how to check your current status on each one. 

For these tests you’ll need a pen and paper (or something to take notes with), a step / stool / solid box to step on, and plenty of space to hop around. As you go through these tests, take notes on how you do in each one and we’ll review them below.

If you prefer to follow along with a video to complete ACL Risk Assessment tests, you can do that here.

ACL Risk Factor 1: Joints and Mobility

Test 1: Foot Arch

The arches of our feet act like shock absorbers for our body weight. Stand on a firm, flat surface with your feet (barefoot or in socks) in a neutral stance. Take a look at the arches of your feet. 

If your arches are either very flat or very high, this is a risk factor. Either of these extremes put extra stress on our knees!

Test 2: Joint Mobility

Joints that are very lax rely more on the ligaments and muscles to hold them in place. The ACL is a ligament, so loose joints can mean the ACL is doing more work, making it more vulnerable to injury.

A simple test for joint mobility is to take your thumb and bend it down toward your forearm. Stop when it’s painful, don’t force anything! 

If your thumb easily touches your forearm, you probably have a high amount of joint mobility, which is another risk factor.

Test 3: Squat Mobility

For this test, grab something like a broom, paddle, or ski or hiking pole. Hold onto it with both hands, using an even grip a few inches wider than the width of your shoulders. Holding your “bar” directly above your head, go into a full squat.

Ideal squat mobility includes a couple of things. First, see if you’re able to squat to a depth where your hips are parallel with your knees without your heels lifting off the floor. Second, see if your arms stay above your head in generally the same position, or if you start to collapse and pitch your upper back and arms forward. 

If you notice either of these things in your squat, it’s a sign of some immobility in your body that indicates risk for ACL injuries.

ACL Risk Factor 2: Core Strength

Test 1: Knee Crunch

Lie down on your back for this test. While keeping your back flat on the ground, lift your legs off the ground and make an “L” shape. Try to curl your knees toward your chest. 

If you can get your knees all the way up to your chest, that’s great! If not, core strength might be a risk factor for you.

Test 2: Boat Pose

Sit down on the ground and balance on your sit bones, making a V shape with your thighs and torso. First, do this with your knees bent, lower legs parallel to the ground. To further test your core strength, try straightening your knees, then straightening your arms. 

The more of these extra challenges you can do without your back and core rounding, the less injury risk you have.

ACL Risk Factor 3: Lower Body Muscle Balance

Test 1: Landing Stability

Grab a small step or box that will support your weight. If it’s safe for you to do so, stand up on the box, gently jump off, and land softly on the ground. When you land, notice if your knees track over your feet, or if they collapse or wobble at all with your landing. It can be challenging to notice this in real time on yourself, so try doing it in front of a mirror or recording yourself for a better look. 

Wobbly knees on the landing is a risk factor, and means you want to build strength in your posterior chain (glutes, hamstrings, calves, and back muscles) and the muscles that stabilize side-to-side action.

Test 2: Quad Dominance

Stand in a neutral stance and start to hop up and down, staying loose and light on your feet. Keep going till your muscles start to burn. Stop and do a scan of your lower body muscles. What’s burning the most? Is it just your quads, or do you feel a burn in your hips and booty, too? 

If you’re only feeling it in your quads, that’s a sign to strengthen your posterior chain. Weak glute activation is a common risk factor for knee injuries.

Test 3: Single Leg Hover Test

Grab that box you used for the landing stability test! Stand on the edge of the box with one foot, and let the other foot hang in the air. Using a mirror, check the alignment on your hips. 

If your hips look level, parallel to the ground, that’s great. If your hip on the free leg sags below the other side, this is another sign of weak hips. [Explore more about this action specifically in our blog The TuTu Test

Test 4: Single Leg Hops

Imagine a plus sign on the floor, separating the space into four boxes. Hop on one foot between all four imaginary “boxes,” moving right, back, left, and up. Keep doing this for a set amount of time, maybe 30 seconds, and count your reps. Do it again on the other side, and see how closely the number of reps lines up. Ideally, it’s about the same number for both legs. 

If the difference in the number of reps is more than about 10%, you might have an imbalance between sides, which will put more strain on your knees.

The Big Picture

Now that you’ve gone through these different tests for injury risks, grab your notes! See if you can identify themes of which categories have more vulnerabilities for you personally, and which are strong.

For instance, maybe your core strength is good, while these tests revealed some weak hips and wobbly knees. That’s great info to have! Now, you know you can plan to maintain your core strength while working on posterior chain training with more intention.

Awareness is a key step in injury reduction! When we recognize our weaknesses, we can intentionally strengthen them. That’s a huge win! 

Exercises like Pistol Squats (above) are included in Ski Babes and are a part of ACL injury rehabilitation and injury prevention.

Reducing ACL Injury Risk through Strength Training

I get it – it might feel overwhelming to plan out how to reduce these risk factors. But that’s where Mind & Mountain comes in! Our training programs are designed with just that in mind. We do the work of figuring out how to train to prevent knee injuries for you!

Around here, we're big believers in strength training for snow sports enthusiasts like skiers and snowboarders. Not only will training help you get stronger for long days on the slopes, strength training has a protective effect on injuries. Training and building strength through multiple planes of movement helps build resilience in all those little muscles and soft tissues that keep your joints and bones happy and healthy.

Ski Babes and Summer Strong are designed with these ACL tests and knee vulnerabilities in mind. Our programming is full of exercises that address the mobility, core strength, and lower body muscle balance that help prevent (and recover from) ACL injuries.

Our winter strength training program, Ski Babes is not just for skiers! It’s a training program created with winter sports (snowboarding, skating, biking, hiking) in mind, but is also appropriate for anyone looking to build more functionality in their bodies and prevent injuries. 

Ski Babes will help you gain functional strength, prevent injuries, and have more fun this winter. These workouts include plenty of moves to support happy knees, including building a strong core and posterior chain.

Are you ready for a strong, confident winter? 

We’re enrolling now: Midwinter round of training starts November 27th!! We can't wait for you to join us in our welcoming community. Visit this page to check out your options for enrolling.


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