Welcome to winter (finally)! Snow is starting to accumulate; snowcats are grooming both JHMR and the King, and the backcountry is getting better by the day. Yes, both Dr. Laura and I are avid boarders, however today, I want to take a minute and address you “old fashioned” skiers (you know I love you despite this differences). Regardless of what you use to get from top to bottom, all that matters is the size of the smile on your face – well, that and arriving with all body parts intact.
Why do so many skiers suffer from ACL injuries every year? The knee itself is built to be a strong and stable hinge joint. The numerous ligaments of the knee help to provide stability in the face of some seriously strong muscle groups pulling in various directions. Why then does the ACL tend to take the majority of the abuse for skiers?The function of the ACL is to prevent forward glide of the tibia under the femoral condyle as well as prevent rotation of a straightened knee. Think about the endless terrain variables, snowpack and surface conditions, sudden elevation changes and other unexpected natural obstacles you are faced with on the slopes, and add in the rotational vectors applied by carving through the aforementioned variables.
It is easy to imagine how this ligament could get damaged, especially when you isolate each leg to a separate ski and factor in overall strength, fatigue, previous injuries and compensation patterns to the mix. Additionally, the ski is so much longer than your foot. This length creates an excessive force on the knee by acting as a powerful lever. Think length of a crowbar when trying to pry a stubborn nail – the longer the lever, the easier to remove that nail. Applying that logic to the skier, the nail becomes your ACL! Your body’s defense is the hamstring and quadriceps muscles which act to counter the torque applied by the ski’s lever arm. When those muscle groups are weak or fatigued, the ACL is left unprotected.
Experts have deduced an “optimal” hamstring to quadriceps strength ratio which, to be completely honest, is difficult to assess and fully comprehend. What you need to know is that quadriceps strength tends to overpower the hamstring, leading to an increase in susceptibility of the ACL to injury. Therefore, I stress the importance of focusing on the posterior chain when preparing for ski season!
Experts and laymen alike have varied opinions on ski fit classes. One thing a good ski fit class should focus on is balancing the hamstring to quadricep ratio – the more posterior chain exercises the better! Remember, this is simply prepping your body to function correctly on the slopes. Start with weight training for strength and then laps to build muscle endurance. Pay attention to your body. Even those with adequate strength can fall prey to an ACL injury when fatigue is ignored.
Maybe you like to do your pre-season or in-season strength training on your own. Great! Here is a list of great posterior chain exercises you might want to consider including. New to this kind of thing? We’re here to help. Laura and I would be more than happy to help you out in your journey. We also have some great contacts in the stellar Jackson health and fitness world!
Posterior Chain Exercises:
Squat (front, back, goblet, split)
Lunges (various)
Deadlift (regular and sumo)
SLRD
Glute-ham raise (bilateral and single leg)
Back extensions
Good Mornings
KB Swings
Happy Holidays and Happy Shredding!
