Friday, 13 April 2012

Running thoughts

I have begun reading Run Strong (2005), edited by Kevin Beck. Each chapter is written by a different author. Chapter 1 focuses on running mechanics and penned by Jack Youngren. His expertise lies in the field of cancer cells and insulin production in humans. Gleaning over his resume I see his BA and MS is in human kinetics.

In his article he refers to work done by Peter Cavanagh that outlines characteristics which constitute a highly efficient running gait. Here are the 'ideal' characteristics found in someone with good running economy:
  • average to below-average height
  • a leg structure that distributes mass closer to the hip
  • a narrow pelvis
  • smaller-than-average feet
  • an optimal stride length
  • minimal bouncing while running
  • more acute knee angle during swing
  • decreased ankle extension at toe-off
  • some degree of stiffness in the muscle-tendon structures
  • a non-flamboyant arm action 
This list was not made by Youngren himself, though he compiled and commented on it. I don't mean to shoot the messenger or create a strawman but I will be frank: some of these items are redundant, others trivial, and I see at least one that is wrong. Also Youngren implicates himself front and centre with the following passage:
...many of these routes to improving [running] economy are closed to you. Sure, it would be nice to surgically narrow your pelvis, and binding your feet may have worked during development, but it's hardly an option now. 
Was he being facetious about the foot binding? I hope so. Probably. It's a risk to joke about something that could be taken seriously (I don't know who or how. Parents making their kids run in tight shoes?).

Footbinding aside, I get the impression his phrasing of these characteristics as 'closed routes' implies it is advantageous to have as many of them at birth as you can. It's the sort of advice that leads to looking in the mirror then losing faith in your future as a runner. "I'm too tall, my hips are too wide, I have big feet", etc.

Assuming average and below-average people dominate running height-wise, it is needless to point out small feet are also common. If short people dominate, it would be incredible to discover they also have large feet. In other words very typical, proportionate people run fast. But do you require a short stature to run fast? I don't see this as true. Naming a few people, we have Ussain Bolt at 6'5", Paul Tergat at 6' even, Robert Cheruiyot at 6'3", David Rudisha at 6'3", Christ Solinsky is 6'1" (and not even that slender, either). Alberto Salazar is 6', and don't forget Craig Mottram at 6'2" on the cover of the book. Paula Radcliffe at 5'8", which is above-average for women (avg. height in UK is 5'4"). Since she's the fastest female marathoner in the world, could it not be said being tall must me an advantage? Or is she, among elite runners (who are by definition outliers) an outlier among outliers? Does that even make sense? Why should these individuals be disregarded? Is there something especially unique about them compared to other tall persons?

Heck, you might have even hear someone say "he/she has long legs, I bet they'd make a good runner". I personally know some very fast short and tall runners. The 10,000m Olympic gold was decided in 2000 between Tergat and Gebrselassie; they were  seven inches apart in height but finished less than 1/10th of apart in time. It seems height may have little impact on running performance, intuitively true since a longer stride cancels a slower turnover, or a fast turnover compensates for short stature. So why are elite runners short? I'm no auxology expert, but this is where some intuition and laptop research led me.

Recall that Africa is currently the dominant running force and people there come from impoverished backgrounds. Am I making this up? Here's at least one article I can cite:
Cohort heights for adult female vary systematically with health and nutrition in Sub-Saharan Africa.
Firstly, it's well known that diet will affect adult height and why North Koreans are much shorter than their South Korean counterparts. Runners showing promise will of course be enrolled in training camps and receive the best nutrition thereafter but we are speaking of the (irreversible) early stages of development. Humans males -when properly fed- reach a normal height close to 6', like in Norway; here is a list of countries ranked by average height. Where are the poorest countries? At the bottom of course. Rudisha of Kenya is a tall guy and he's the fastest 800m runner in the world. Is he fast despite his height or because of it?

Secondly, among wealthy (hence tall) countries one should consider how other sports selectively seek tall persons. Volleyball, swimming, tennis, basketball, rowing, and boxing will pick the tall kids out of a crowd (they're easy to spot) and develop them thereafter. It is interesting that soccer, a sport that relies on a lot of running, has no special height advantage (I thought it would given the advantage in ball headings, but apparently soccer elite span 95% of the normal height range). To be a tall runner, however, means ignoring the impulse to try other sports that favor your height. An athletic, short person will show bias to running because

1) tall people have a competitive advantage in many other sports (but not running). What are the odds of a 6'8" jogger not getting groomed for basketball?

2) people from low income families tend to be shorter and would therefore embrace an inexpensive sport.

Note that Bolt is 'too tall' for sprinting. Oh well. Read this to see what I mean. Also note that the 'ideal' height in sports changes with the wind. Gretzky was 'too small' for brute-force style NHL hockey...until he changed how the game was played. 

Enough about height. If you're not doubting this dogma by now you probably never will.

Most of the other items in Youngen/Cavanagh's list are certainly good to take note of, but ones like knee angle, minimal bouncing, and ankle extension are impossible to control in the moment of action. If you try, you will lose focus on other aspects of your stride. It's a losing battle. Another item listed, the mass distribution on your legs, is a by-product of the fluidity of your running mechanics. Large calves come from poor landing and your body's attempt to stave off lower leg injuries. Big calves mean you're doing it wrong.

Perhaps the best advice of that listed is to avoid swinging your arms wildly; you can control your arm far more than passive leg movements.

The bit about the narrow pelvis seems true, mechanically speaking, especially after considering the obstetrical dilemma in women. But men have narrower hips, so almost all men are fine. Women are collectively faced with the same dilemma (women tend to run about 90% of the speed of men at any given distance; I wonder if this is why). And measuring hip width is harder than it sounds (old article, but interesting). Muscle and fat also affect the width (if, say, measured by a tailor who doesn't care where bone ends and fat begins). Then again your hips might just have to get stronger to avoid problems:
The results of this study show that hip abductors and external rotators were significantly weaker between the injured and unaffected legs of the injured athletes. In addition, injured collegiate female athletes exhibited global hip weakness compared with age- and sport-matched asymptomatic controls.
Youngren includes out 'optimal stride length' is a factor you can control. Yes, it certainly is. Or is it? For starters stride length is tied to running speed (Jack Daniels' often quoted 180 strides per minute is not some universal constant). Perhaps consciously improving your bio-mechanical efficiency is not as easy as it seems:
The question regarding our ability to significantly improve economy through bio-mechanical training remains unanswered.
And Youngren's chapter is exactly this: instructions on plyometric drills that improve your biomechanical efficiency. But many experts don't know if this necessarily helps; each exercise may affect each persons differently. If you run 'incorrectly' what are the chances you are doing the drills any better? We are approaching some tricky territory. 

Conclusions? I have read time and again that the sheer feasibility of consciously changing your biomechanics is highly questionable, that plyometric drills at best aid your running in an indirect way and themselves require years of technique refinement (hence you'll master running and plyometrics simultaneously, begging the question which came first). Anecdotally I'm aware that practices involving conscious stride alterations often lead to injuries (I'm including my own experiences here). 

Solutions? No easy one. Maximizing your comfort at various speeds goes a long way. And keep experimenting, cautiously, with new drills, strides, and varied running speeds in hopes that they find you new comfort zones. Maximize comfort, minimize (but don't omit) pain. Pain is like a 1,000,000+ Scoville hot sauce; better to add too little than the other way around. But no spice at all means no kick.

Are these guys all the same height? 

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