While there were lots of interesting comparisons to make between runners in the 2016 NYC marathon, what really jumped out at me was the unusual thing both Molly Huddle (3rd place woman) and Ghirmay Ghebreslassie (1st place man) were doing with their legs.
Here are screenshots of Huddle:
As you can see, the space between both runners’ knees is larger than between their hips or feet. In the first pic Huddle is in the same part of her gait cycle is Joyce Chepkirui to the left but look how much farther apart Huddle’s knees are. Same for Ghebreslassie’s first pic, where you can see his stance knee bows outwards unlike Lelisa Desisa’s or Lucas Rotich’s to the left.
In other words, they’re both running a little bowlegged.
It’s incredibly common to see runners of every level do the opposite, running with their knees closer together than feet or hips, but it’s rare to see legs bowed outwards, especially in elite runners.
Here, for comparison, is a screenshot of Huddle in the background and Sally Kipyego in the foreground–Kipyego’s knees come together while Huddle’s move apart.
I’m using the term “bowlegs” because it’s describes how their legs appear. What I can’t tell is to what extent their legs are actually built that way vs. the appearance being created by their coordination.
There are actually three things apparent bowlegs could be, however:
1. a medical condition of bone malformation in which the knees remain apart when the legs are straight and the feet together in people over the age of 3 (in infants and toddlers it’s normal).
It’s caused by rickets, among other things, and I’m taking the time to mention it here despite the fact it’s a massive digression from discussing the race because in recent years the condition has increased in prevalence due to vitamin D deficiency from lack of sun exposure/overuse of sunscreen and inadequate dietary/supplement consumption. You particularly need to be aware of this because vitamin D status has a huge effect on athletic performance.
In this case the medical term for the shape of the legs would be genu varum and I can’t say whether this is what’s going on with Huddle and Ghebreslassie; I’m certainly not in the business of making medical diagnoses by watching races.
2. a habit of standing with knees locked. This moves the knees farther apart as a few things happen simultaneously with this habit: the knees hyperextend, the legs rotate inwards so that the knee hyperextension pushes outwards rather than straight backwards, the pelvis tilts anteriorly (forward), which hyperextends (arches) the lower back, and all of this allows the legs to rotate inwards even further, moving the knees farther apart.
This is not what’s going on with Huddle and Ghebreslassie, as that’s a pattern in standing that changes completely when the person starts to run. Odds are, though, that a person who stands like that doesn’t enjoy running due to lax ligaments and a feeling they have no “spring.”
3. a habit of externally rotating the legs when flexing the hip joints. Try this yourself: stand with your knees a little bent and then without moving your feet, move your knees apart, then towards each other. Do you feel how the legs actually rotate to do this? For even more clarity, put your index fingers on the centers of your kneecaps to help you see how the knees don’t only move closer together and farther apart, but also turn towards and away from each other.
That’s likely what Huddle and Ghebreslassie are doing.
The reason it’s unusual to see is that it can actually shorten stride length. Because the pelvis moves when you run, your leg is actually a little externally rotated as it swings in front of you prior to footstrike (your knee is ideally pointing forwards but your pelvis is turned slightly away from it, meaning the femur is externally rotated and abducted in the hip joint in addition to being flexed.) That’s fine, no problem for these two runners.
However the opposite is true once your pelvis has passed your foot. The pelvis turns towards your stance leg, meaning the femur is internally rotated relative to the pelvis. If you’re not easily able to do this, you leave the ground and start bringing your leg forward sooner, before much internal rotation would be required. This limit on your stride length ends up limiting your speed.
This is an ironic outcome for runners who are trying to improve their hip extension by consciously activating their glutes. The gluteus maximus is an external rotator of the femur in the hip joint, meaning trying to get it to fire at the wrong time–near toe-off–interferes with internal rotation of the femur in the hip joint and, as I said, actually reduces hip extension.
Is this happening to Huddle and Ghebreslassie? I found it tricky to tell from the race video but we can look for clues in what the rest of their bodies were doing, and you can look for similar clues in your own running.
In addition to the similarity I’ve been discussing, there’s also a big difference between how the two run. This difference lies in their trunk and head movements, where they’re at opposite extremes of the elite field for this race.
Huddle retracts her head so approximately the top half of her spine is vertical. Her neck appears to shift little when she runs and her head moves only minmally side to side. Though her hands were swinging up to heart height earlier in the race, as she grew fatigued they dropped lower and moved ever farther away from her trunk, suggesting that the higher armswing had been artificial, something she was doing on purpose rather than something that occurred as a spontaneous result of the way she was moving the rest of her body.
The retracted head and lower, wider armswing go together, and both occur when the upper body isn’t moving sufficiently (which then tends to discourage the pelvis from moving sufficiently as well). And both usually accompany an increased lumbar curve (lordosis) in which the pelvis seems to be tipping way forward, which can also produce a pronounced forefoot strike. I wrote a bit about this in one of my Rio Olympics blog posts.
Huddle’s retracted head and forefoot strike actually suggest that she may be hitting a limit of hip extension–maybe it’s a skeletal limit or maybe with a little more internal rotation of the femur just before toe-off her head would move forward, upper body become a little more mobile, and speed increase. I’ve seen this happen for many runners, especially ones with low back discomfort.
On the other side of the scale, in the final picture in the Huddle collage you can see that the ankle and foot of her swing leg are extended (plantar flexed). Kudos! You almost never see that in American distance runners and it’s helping her a lot, preventing the chronic hip flexor activation that’s a common barrier to good hip extension, making it easier to bring her legs forward, and making her springier and faster.
Now let’s consider Ghebreslassie. He flexes his upper body slightly–you can even see it after he’s crossed the finish line and is just walking around–and his head moves a great deal side-to-side. In this he reminds me of Zersenay Tadese, whose upper body is similarly mobile and head forward (though a bit less flexed).
It’s not only his head that moves a lot, his entire spine does. In the pictures of him from the front you can see his pelvis is more tilted (swing side dropped) than Desisa or Rotich. This is why his swing knee comes through straight underneath his hip joint when Huddle’s is a bit out to the side.
This is a man who uses his glutes–all of them–very well. From his very forward weight to his very mobile pelvis and very large lateral weight shift his glutes are handling a lot of force through a large range of motion in stance. And this is accompanied by one heck of a spinal engine (with a nod to Gracovetsky).
This is a very powerful way of running.
He could take it up a notch, however, by tweaking his armswing to bring his knuckles to his midline. Right now his hands are moving more “nip to hip,” (not an attractive phrase, but clear) which rounds the upper back and pushes the head forward more. (Yes, yes, I know, pulling your shoulders back and moving your hands more front-to-back is supposed to improve your “posture,” but it does it through increasing muscle tension and as soon as you fatigue your head pokes forward excessively.)
With hands moving more to the midline he could unflex his upper back and lean his whole torso forward better. Maybe all this arose for him because he also doesn’t internally rotate his extending leg enough, I honestly can’t tell from the race video. I’d start with the arms, though.
Here’s race video so you can get a look at the actual running:
An interesting place to look is 33:40, where you can compare the leg and foot action in men’s pack: Ghebreslassie’s knees wide knees, with foot placement narrow and externally rotated, most other men’s knees and feet in a line, with feet only slightly externally rotated.
At that point you’ll also see Dathan Ritzenhein with legs and feet wide, and arms wide as well, indicating that his trunk is stiff and his pelvis is not moving well. The most imporant sign of this, however, is the visible acceleration of his feet downwards towards the ground as if stomping, unlike all the other men in sight. This is a result of hip flexors too short throughout the gait cycle and it is very damaging. When I saw that right from the outset and yet saw him in the lead I was pretty sure he would DNF. I’ve never seen an elite runner run like that, lead early, and be anywhere in sight at the finish, and indeed few even make it to the finish. Sad but true.
For views of Molly Huddle look early in the race and again just after Mary Keitany crosses the finish line.
While it’s tempting to write about Mary Keitany again, there’s not much to say I haven’t already said except it seemed to me she was pulling her head and upper body back a little, which I haven’t seen before. Overall, though, her technique is awesome. Truly.
Thanks to everyone who participated in my blog post topics survey! I was actually surprised to see that the majority of people’s requests were for topics I’ve already covered, especially for ones relating to injury. It’s easy to miss things I’ve written, though, with 169 posts on the site as of today.
So I’ll be spending the next few months organizing posts on these topics into resource pages so it’s easy to see where to go for the information you want. I’ll also look for gaps in the info that I can fill in with new posts.
However I still need your help chosing a movie to do a running form analysis of in the spirit of my Lord of the Rings analysis a couple of years ago. It would be best if there are clips available on YouTube so I can post them with the analysis.
So please leave a comment below suggesting a non-running-related movie in which a character runs, and I’ll pick one and write about it next month.
Finally, the holiday season is bearing down upon us with alarming speed. I’ll have some thoughts for you on Buy Nothing Day this coming Friday, and discounts on gift certificates for video analysis and my online running technique camp over next weekend and on Cyber Monday.
If you’re in the US, enjoy your Turkey Trot and have a great Thanksgiving!
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Jae Gruenke, GCFP, is a running technique expert and Feldenkrais Practitioner. Known as a “running form guru,” she is the Founder and CEO of The Balanced Runner™ in New York City and The Balanced Runner UK. She has helped runners from beginner to Olympian improve their form to become pain-free, economical, and fast.