John Davis

Written by John Davis


Hip strength and running form: The role of hip drop in running injuries

A lot of readers have been asking for articles on biomechanics and running form, and as this is an area of intense interest for me, I’m eager to do more writing on that front.  But, because even basic questions of the “what is good form?” sort straddle the boundaries between scientific knowns and unknowns, my articles will necessarily take less of a “hard science” tack.  Now, we aren’t tossing everything out and starting anew, but working on this front is going to require a bit more predicting and inferring than we’ve had to do in the past.  That being said, I’m eager to jump right in.

Forward and back versus side-to-side movements in runners

When most people picture a runner with “good form,” a very specific type of image usually springs to mind: a young, lean runner gracefully floating along.  Our mind’s “camera” inevitably shows a lateral view, which highlights a very peculiar kind of bias in how we think about running form: that it is primarily related to motion in what biomechanics researchers call the “sagittal” plane (essentially, forwards and backwards).

But much of what’s being revealed in high-tech biomechanics laboratories around the world has less to do with forward-backward motions like body lean and leg extension and more to do with side-to-side  motions, particularly in the hip and knee.  That’s where we turn our attention today.

Importance of side-to-side stabilization for runners

As one of my articles several weeks ago pointed out, many runners who suffer injuries have weak hip stabilizing muscles.1  Among these muscles, the ones which are most often weakened in injured runners are the abductors and external rotators.  Aptly, they abduct and externally rotate the hip.

Interestingly, and perhaps not surprisingly, research by Irene Davis at the University of Delaware has shown that one good predictor of future injuries in healthy runners is a mechanical evaluation of hip mechanics: runners who have excessive hip adduction (opposite of abduction) and internal rotation are at an increased risk of developing injuries in the knee and IT band.2

The logic is pretty simple, then: weak abductor and external rotator muscles cause excessive adduction and internal rotation during running, since the hip muscles aren’t strong enough to resist the forces from ground impact.

Relationship between muscle strength and muscle function

Unfortunately for us, however, the relationship between muscle strength and muscle function isn’t perfect.  Other findings indicate that the link between muscle weaknesses causing injury is weaker than we’d expect, because another factor plays a role: neural function.3

Essentially, this is the way in which you “choose” to run.  I put “choose” in quotation marks because it isn’t usually a conscious choice, but rather it’s a repetition of neural patterns that are strongly engrained in your brain.  You don’t have to think “move left leg, move right leg” when you run; it just happens.  Of course, if we could peer into the brain’s raw instructions, it’d be a bit more complicated than “left, right, left.”  It’d be something more along the lines of “fire iliopsoas at 40% strength, fire rectus femoris & gluteus medius at 70% strength” and so on.

In other words, it may be possible that your muscles are strong enough but just aren’t firing in a way that would prevent excessive adduction and internal rotation.

Davis’ lab at U Delaware has a high-tech treadmill that allows runners to see their hip adduction in real-time so they can learn what it feels like to run with a “proper” stride (or at least one which should reduce the risk of knee injury).4  This technology is very new and very expensive, so it’s not something most runners will be able to use in the near future.  And it’s very tough to evaluate hip adduction on your own.  But nevertheless, in my own experience, I’ve found that it’s productive to look for one of the other consequences of improperly firing hip abductors: hip drop.

Hip drop and running injuries

What I’ve labeled “hip drop” is more properly called “Trendelenburg gait,” not exactly a quick phrase you could shout at a high-schooler with deteriorating form in a cross country race.

Remember, during the “stance” phase of the stride, the body is supported by only one leg.  So, when your right leg is planted, it means your entire left side is “cantilevered” over your left hip.  If the right hip muscles aren’t firing correctly (either because of weakness or just bad neural patterns), the pelvis and upper body will tilt downwards on the left side.

hip drop running injuries

This is commonly demonstrated with illustrations (above), but is also fairly easily spotted in real runners too.  The problem is usually exacerbated during races and long workouts, probably because your body as a whole is getting tired.

You don’t need a high-tech treadmill to spot hip drop.  All you need is a friend you run with, or a treadmill plus a mirror or video camera.  If you see excessive hip drop, see if you can consciously change it by focusing on “standing tall” and keeping your pelvis level.  If you’re having trouble doing that, it probably means you’ve got weak hip abductors and external rotators.  You can address that with some side leg lifts and “clamshell” exercises.

RunnersConnect Insider Bonus

Download your FREE Hip Strengthening Exercises Guide inside your Insider Members area.

Download a video and PDF version of the 5 most effective hip exercises for runners. You’ll get more images, full descriptions on how to perform and a video to help guide you.

Click here to access

Not a RunnersConnect Insider member? It’s FREE to join. Click here to get started

Putting it all together

Hopefully this has been an informative, brief introduction to one aspect of “good running form” that’s fairly noncontroversial and easy to spot without high-tech equipment.

Hip drop is pretty common among runners (as is hip muscle weakness), so use a mirror, camera, or a friend to evaluate yourself to see if your hips tilt when you’re in the stance phase of your stride, particularly if you have had knee or IT band issues in the past.

It band injuries in runners

The runner pictured above, a teammate of mine in college, had IT band issues more than once during his college career, and fixed them only though rigorous strength work.

Now, we can’t yet say that the cause of his problems (or yours) was due to the abductors and external rotators, but a growing body of evidence and experience is pointing in that direction, and while hip drop may not be the best indicator of weak or dysfunctional abductors, it’s fairly accessible to all runners and eliminating it does not seem to have any real drawbacks either.

If you do find that your hips are dropping, you can fix it either by overriding your “natural” gait habits or by doing running-specific strength exercises to shore up your weaknesses.  Fortunately, after practicing standing tall and keeping your pelvis level for a while, it will become automatic, overriding the old stride pattern in your brain.

Hopefully you’ve enjoyed this first foray into the sometimes-nebulous universe of what constitutes “good” running form, and I look forward to reading your comments and questions.

Free Injury Prevention Course

Learn What is Causing Your Running Injuries and How to Fix It

Here’s what we’ve got for you

The scientific, underlying cause of your injuries and how to fix them.

The mistakes you're making in training that are leading to your injuries.

Case studies with specific examples of runners exactly like you and the strategy they implemented to get healthy


1. Niemuth, P. E.; Johnson, R. J.; Myers, M. J.; Thieman, T. J., Hip Muscle Weakness and Overuse Injuries in Recreational Runners. Clinical Journal of Sports Medicine 2005, (15), 14-21.
2. Davis, I.; Noehren, B. In Prospective Study of the Biomechanical Factors Associated with Patellofemoral Pain Syndrome, American Society of Biomechanics Meeting, Palo Alto, CA, Palo Alto, CA, 2007.
3. Heiderscheit, B. C., Lower extremity injuries-is it just about hip strength? Journal of Orthopaedic & Sports Physical Therapy 2010, 40 (2), 39-41.
4. Noehren, B.; Scholz, J.; Davis, I., The effect of real-time gait retraining on hip kinematics, pain and function in subjects with patellofemoral pain syndrome. British Journal of Sports Medicine 2010, 45 (9), 691-696.

Connect with Jeff Gaudette on Google+

10 Responses on “Hip strength and running form: The role of hip drop in running injuries

  1. This is a great article. I have been working on changing my running form for a while now. By far the hardest part for me has been running with level hips. I have to consciously think about it. I am able to run longer distances each time before I get tired of it. I know that eventually it will become second nature. Thanks for the great article.

    • I have been in PT for weak hips for 6 months (!!) A mistake I made was when the PT first told me (months ago) that it was “weak muscles,” was continuing to run thinking to myself [wrongly], “I know how to ignore sore muscles…they’ll only get stronger.” I’ve ended up with stubborn tendinosis, specifically where the IT Band attaches to the Iliac Crest.
      I took about a 30 day break whilst traveling – each time I tried to run while away, pain. I am now core strenghtening as well as trying (instinctively, w/o being told) to run with my hips square and pulled forward (not letting the lower back curve out) & it does help, but requires effort. Little did I know it was “hip drop” as you write about — that’s definitely what I have been doing & am grateful for this article.

      Interestingly, I believe I had been spared this injury until now, despite being a 20-40 mile/week runner/marathoner for the past 25 years, because of an exercise that gets maligned by trainers & PTs — old-fashioned Army sit-ups, with the feet anchored/hands behind the head/ going all the way to the floor and all the way up. Doing hundreds of these sit-ups each week as part of my “job” (on active duty), plus push ups (which strengthen the core), I was more or less injury free. Now retired, I had slacked off, & the right hip started to “drop”, just like you describe.
      I know serious athletes & PT schools poo-poo this old form of sit-ups, but I sure can feel it pulling & working the weaks spots (e.g., gluteus medius, hip flexor) when I do them, & it does help the abs. Perhaps another suffering (& aging!) runner reading this will want to try them. (along w/ push-ups/planks/clams/etc.) Sit-ups also can warn is where such hip-dropping is going to develop — my whole career, having to do 80 or so of these fast in 2 minutes, I always noticed that my butt would scoot over in one direction, to the side now injured w/ tendenosis. It’s odd how one side is weaker — the right, which I would have otherwise thought of as my dominate side.
      Best wishes,

    • Hi Samuel,

      I am thrilled this post helped you so much. I really hope it kicks the nagging problem you’re having and allows you to continue running. There is nothing like being able to train pain-free and with peace of mind. Feel free to repost as long as you link back to use somewhere in the article. Good luck with your training!

  2. Thank you for clearly explaining the hip drop issue and not only the permanent solution- strengthening exercises, but also the immediate fix of “walking tall”. Do you feel this is equally valid for not just runners, but also older folks who have ingrained postures. I have medial knee pain.

  3. Thank you very much for this very informative article. It really helped a lot with my lower leg injuries. Now I can run with more confidence knowing that I won’t easily get injured when I run/jog if I continue to infuse hip exercises to my cross-training sessions and follow your tips religiously. 🙂

  4. Pingback: PEI Marathon Blogger: Physiotherapy Fun » Heather Ogg Photography PEI | Prince Edward Island

  5. Helpful video. I am finding that flexing the foot to at least 45 degrees and pushing off while thinking about driving the knee straight ahead, standing tall, lifting my gaze to the middle distance, and aligning my posture and lean so that my entire body absorbs impact like a spring when my weight is on the ball of my foot, all of these things combine to take stress off the knees and calf. Currently I’m focused on walking 6.5 miles per day with good form, strengthening my lower back, calves, arches, and glutes, plus leg strength and flexibility training. I would be interested in hearing about differences between good walking form and good running form.

Leave a Reply

Your email address will not be published. Required fields are marked *

Adding new comments is only available for RunnersConnect Insider members.

Already a member? Login here

Want to become an Insider for free? Register here