Welcome to October, the beginning of hockey season! Growing up loving, playing, and breathing hockey, October is like Christmas. So in honor of the kickoff of the NHL season, I’m going to talk about a really common injury in hockey — the dreaded groin strain. Studies have found the incidence of groin strains in professional hockey players to be 8-10% of all injuries and over 40% of all muscle strains, with possible recurrence rates over 30%. That ends up to be lot of NHL games missed. Not good if you’re in the hunt for Lord Stanley. A big contributor is the fundamental movement of the skating stride – where your glutes are prime movers and your adductors and hip flexors are prime stabilizers. This leads to a common profile of muscle imbalance and eventual muscle strain.
But what if I told you that this could be avoided? It all starts at the hips.
A study by Tyler et al in 2001 looked at the hip strength profiles of 81 NHL players and followed them over 2 seasons. The authors measured abduction strength (muscles that bring the leg out to the side) and adduction strength (“groin” muscles that pull the leg in). What they found was that hip adduction strength was 18% lower in the players who ended up sustaining a groin strain. In addition, players whose adductor strength was less than 80% of their abductor strength were actually 17 times more likely to have a groin strain!
Now what? Let’s say you find out you or your hockey playing client has a low adductor to abductor ratio. Can we change this? Tyler et al sought to answer this question in a study published in 2002 where they took “at risk” NHL players (<80% ratio) and put them through an intervention program consisting of adductor strengthening and sport specific exercises. The authors found a significant reduction in risk by implementing this intervention program.
Although there is more research to be done, those in elite hockey are definitely interested in what looks to be a way to prevent a very common injury. In fact, over the last couple months I have been involved with testing at the university level for a colleague’s study as well as at the professional level for injury prevention program prescription as part of my Sports Physical Therapy Residency.
What are adductors? They are a group of muscles commonly referred to as your “groin muscles,” located on the inside of your leg. Your adductors pull the leg towards the body, but they are also very important stabilizers. That means they help you to stay balanced when you are doing challenging dynamic exercises such as jumping or skating.
To strengthen these muscles you can start with something easy to activate them and then slowly add weights or resistance bands. The general motions will be bringing the leg in and squeezing together.
1. Bottom leg lifts
In this exercise your are bringing your leg toward midline. This can be done off the floor like this, or it can be done in standing. When you do it in standing, you can experiment with therabands or even a slide board when it starts to get easy. Try to vary the speed as well, making sure to do some reps where you are lowering your leg slowly to fire the adductors eccentrically.
2. Bridge with ball squeeze
In this exercise you are doing a normal bridge but squeezing your knees into a ball at the same time to fire your adductors. You can do the same movement with single leg bridges too by holding the other leg straight with your knees in line. I like this exercise because it works the adductors along with the hip extensors and your core, which is a really powerful combination. Just remember that this shouldn’t be your only exercise since it is also working the hip abductors.
Squeezes can also be done with the legs straight. It’s good to consider exercises where your legs are straight as well as exercises where your legs are bent in order to hit the different fibers of the adductor muscles.
The same can be said about stretching position. The 2 photos above demonstrate a stretch with the leg straight (3) and one with the leg bent (4). You can also use a form roller for mobility drills, but keep it short. Remember that the main goal is to strengthen the adductor muscles. If you overstretch, it’s possible to do the opposite of what you’re going for here.
Finally, it’s important to incorporate dynamic and sport specific drills as well. Athletes can start with generic stability exercises that challenge all of your hip and core musculature such as lateral hops, zig zag hops, jump landings, and agility ladder drills.
At the same time, you need to be doing exercises that are sport specific. For a hockey player this can be advanced exercises on the slide board as well as exercises on the ice. For other athletes this will look a little different. The most important this is that your body starts to learn how to use the strength you’re building in a functional manner that can help you improve performance and decrease injury risk in your sport.
Good luck — and for you hockey players, make sure you give yourself a hip check!
Tyler TF, Nicholas SJ, Campbell RJ, Donellan S, McHugh MP. The Effectiveness of a Preseason Exercise Program to Prevent Adductor Muscle Strains in Professional Ice Hockey Players. The American Journal of Sports Medicine 30:5, 2002.
Tyler TF, Nicholas SJ, Campbell RJ, McHugh MP. The Association of Hip Strength and Flexibility with the Incidence of Adductor Muscle Strains in Professional Hockey Players. The American Journal of Sports Medicine 29:2, 2001.