Hip weakness and knee pain
So I was treating a novice female bodybuilder a couple days ago who wants to start running. The problem is that when she gets over 5 miles, her knees start to hurt. After an evaluation we learned that the outside muscles (abductors) of her hips were weak. “How can that be, I work out with weights all the time?” she asked.
Well, when all you do is forward lunges, squats, leg press, leg extensions, leg curls and dead lifts, that is all forward and backward – no lateral strength. As we see below, life is more than forward and backward movements. Side to side and rotational strength is also very important.
Hip abductor weakness in distance runners with iliotibial band syndrome.
Do weak hips cause knee pain in runners?
* Hip “abductors” are the muscles that move the thigh out to the side (away from midline)
Knee pain is one of the most common pains seen in runners New evidence has been coming out in the past few years indicating that we need to look more at the hips for the cause of knee pain.
This new study was small (just five runners and four control subjects), but found that twice weekly hip strengthening exercises for 6 weeks was able to reduce knee pain significantly in runners. The injured runners began the six-week trial registering pain of 7 when they ran on a treadmill and finished the study period registering pain levels of 2 or lower; i.e. no onset of pain.
This 2000 study found that not only did runners with Iliotibial band syndrome have weak hips, but by strengthening the hips, the ITB pain went away…
· 24 distance runners with ITBS and control group of 30 non-injured distance runners
· Females: 21% weaker abductors in the injured leg compared to their non-injured limb and 24% weaker than control group
· Males: 21% weaker abductors injured leg compared to their non-injured limb and 30% weaker than control group
· 6-weeks of rehabilitation of strengthening the hips
· The females increased hip abductor torque by 34.9% in the injured limb. Males an average increase of 51.4%.
· 22 of 24 runners were pain free and still after 6 months follow up
This 2008 study looked at the changes that occur in the entire lower extremity mechanics if hip strengthening exercises were employed. They found that after a 6 week program of hip strengthening,
· Hip abduction and external rotation strength was improved by 13% and 23% respectively
· the rearfoot inversion (the runners heels collapsing inward) was reduced by 57%
· knee abduction moment (the knee collapsing inward) was reduced by 10%
While this doesn’t necessarily say that hip strengthening will reduce knee pain, is certainly confirms that hip strengthening has a major influence on the mechanics of the knee and feet.
I am a big fan of doing core strength work if you’re a runner. While most people wouldn’t consider hip strengthening as “core work”, it absolutely is. Unfortunately, “the core” has become synonymous with doing sit ups, but core muscles are technically any muscle that attaches to the pelvis. The hip muscles would be at the heart of the core.
I am also a big fan of coach Jay Johnson. One of his latest blog posts speaks of how we develop quicker metabolically than we do structurally. In other words, most runners develop strong cardiovascular systems, yet we are very weak in our muscles, tendons and ligaments. A great intro program to strengthening the hips is the Myrtl routine. While this won’t be the cure all, it is a good start to waking up your hip muscles in a variety of directions.
If we break down running into it’s very, very (I can’t emphasize the “very” enough) basic form, it is a one legged squat followed by another one legged squat, followed by another and another. Unlike walking, there is never a point in running when we are on two feet (if you ever find yourself with two feet on the ground in a race, that’s called walking, and you’ve bonked). This makes it important to train on one foot. I have seen many people who are more than capable of doing a heavy squat with two legs, but completely lack the muscular control and balance to do a one legged squat. This is due to weakness in the hips. Check out this video. Right knee one leg squat is good..left one is not so good. Since her left knee caves inward during the squat, it causes major stress on the knee and the ITB. This is from hip weakness and we can assume that during her running gait, there is a certain amount of this inward collapsing of the knee going on every time she plants her foot on the ground…especially when she’s fatigued later in the race.
So to summarize, knee pain in runners isn’t always what it seems. By treating the knees, we may be able to make some headway, but gait analysis and hip strengthening go a long way to treating knee pain.