Sunday, 15 July 2012

Chi running and beyond: efficiency

I went to a short seminar hosted by the Halifax Running Club on Chi Running. I'm sceptical at heart, and running 'techniques' don't intrinsically sound appealing to me. But I have a rule: I don't criticize something until I've tried it first hand. In the past that has included limiting food intake, manipulating stride tempo and breathing rhythms, taking painkillers, barefoot running, and too many others to start about here. I've only heard by second-hand means what it mean to be a "Chi" runner. My ignorance, my problem.

Chi running: what have I learned in a 45 minute seminar? Well, not much in so little time (also kind of the point as our speakers would prefer that you took their more in-depth courses for a fee. The price is not important if you learn something invaluable. It's been said that an afternoon of quality golf swing lessons will do you better than a $1500 set of clubs). But the key lesson of value that was passed along today was internal balance. Make that balance and relaxation, which then enhances true balance by preventing the abuse of stiff muscles.

In terms of balance, the idea is landing on you foot while your foot is under you and not ahead or behind you (the former being far more common). Balance means finding your centre of gravity and using it to your advantage. Our legs are long and complex entities, staring at our toes and ending at our back. What I liked was their aim of running with as little effort as possible. This is another way of saying 'efficient' stride. They began with a self-assesed posture in which we tried to balance without stiffening our muscles, then worked up to baby running steps (very small and quick). Obviously you'd branch out from there and eventually return to a normal running pace. That was the 45 minutes, in a nutshell.

At the end of their seminar my thoughts returned to debates about running efficiency: If you have the most efficient stride possible, you should be going the fastest no? Well, no. And I think Chi running inadvertently proves this. Chi running probably does achieve what it claims to: being able to run many hours pain-free and relaxed. Running efficiency is that often frustrating term used to account for why some with all the right stuff (VO2 max, high-lactate thresholds, etc.) don't win all the races. They are not running as efficiently their comrades. Conversely one with low-end measures who win races do so because they are more efficient with their bodies' energy. What I want to propose here is that efficiency means something very different than most people think.

The first myth I must dissolve is that of efficiency meaning 'using less energy' during a race. A more efficient car can go many miles further than a less efficient one, but who would you bet on in a 10km driving race? No car on earth would have trouble making it to the finish line. Nor would any human, as even the leanest of men are equipped (body-fat wise) to run hundreds of kilometres. Our muscles have enough energy to go about 30 km. Furthermore I proved that running faster does not in itself burn more calories. Combining these two ideas, we realize efficiency is not about conserving energy. We could argue that efficiency for short distances (i.e. less than half-marathon, or thereabouts) is to avoid running up against our lactate threshold. Yet this results in an unsatisfactory line of reasoning as well, for we'd have no reason to increase our threshold if running more efficient is the surest way to success.

Let's back up a moment and gather the elements: The goal of Chi running is to maximize the time spent in a state of running ease and efficiency. I agree with their aim of running at low effort and stress levels. But then I said no amount of efficiency would save relevant quantities of energy expenditure for a non-ultra distance. Worse yet it seems that high-level runners have to fight off lactic burn just as hard as anyone (hence why their tolerance is usually much higher than sedentary folk). So what is efficiency? What does it mean?

I'll give an example from another sport, as it helped me picture the problem. In cross-country skiing it is staid the most efficient way to move from point A to B is by double-poling. Why? It's not important but double poling takes advantage of the low-resistance glide of snow by favouring much smaller muscles (your arms) over more energy demanding muscles (your legs). As long as your arms hold out, it's cheaper energy-wise to avoid taxing all four limbs at the same time. But it's not the fastest way of getting to the finish line, and that's what really matters in a race. The kick-double pole gets you to the end a little faster, and since you're not running out of fuel any time soon who cares how many extra calories it costs?

Since there's only one general way to run (no arm-based substitutes at least), all running techniques get the user to the finish line using about the same energy. The true 'cost' of running is more to do with power (the rate of doing work) and not about total calories consumed. Improving one's power output is almost the entire objective of a competitive runner. Since elites must make do with the same muscle fibres as the rest of us (perhaps containing more mitochondria, but this must be trained also), then the prime limiting factor in running is power performance, a complex baseline with many parameters. The body has many safeguards at different levels, and going beyond this here leads my discussion astray.

Returning to efficiency, be it based on whatever combination of power-limiting physical processes you care to list, it should be apparent that a more efficient movement does not necessarily translate to a faster one. Hence elites build lactic acid tolerance instead of merely bypassing it (while avoiding it as best they can). This is important, that you can find small ways here and there of pushing further into more inefficient -but faster- realms. Here's where the Chi running comes into play: since the fastest way to the finish line is not the most efficient, the Chi technique is a base point which, as we develop in our racing speed, actually desire to move further away from. Like a Taylor expansion, it's a launching point for something close but different.

How is such inefficiency accomplished? One way to increase speed (but lose some efficiency) is to land slightly further ahead of our gravity centre point. From high-speed photography it is clear that marathon elites' feet land ahead of their centre of gravity, more than any chi guru would normally advise (not to mention a complete misunderstanding of racing mechanics by the Somax institute). In the other extreme, a sprinter lands on his or her forefoot so that heels seldom touch ground. Not landing on your heel is very inefficient but it is certainly quite fast for 200 meters. You can also increase your stride rate ever so slightly (Jack Daniels was wrong to imply all elites have the same stride rate). The point is that a chi practitioner and an elite racer will never see eye-to-eye if they are implicitly arguing for two separate objectives, one speed the other efficiency. I should also point out it is difficult to consciously change these parameters, and better to simply recognize and accept them as they emerge from training.

So racing, and hence race-training, is deliberately inefficient. This becomes obvious when you think about what you are trying to achieve: practising a pace that is unsustainable for more than a few minutes (maybe up to an hour or three). That's the central hallmark of inefficiency: unsustainability. But to maximize the duration of an inefficient pace is a slight paradox, no? You are demanding two very different things from your body, to better sustain the unsustainable. The body's attempt at re-equilibration is why there is no simple, obvious way to run faster, requiring a constant juggling of mixed paces and timing. The upside is that once you find yourself racing comparatively more efficiently, you automatically push the pace further and faster into new -but again inefficient- heights. An upshot is that you can run slower paces (i.e. tempo) more efficiently than before (but still not as efficient as jogging), and likely can handle more volume of this type.

Because of this metastable existence in racers we observe these individuals achieve 'breakthrough' performances more often than tiny, incremental ones. This is a rather satisfying way of explaining something that would be otherwise counter-intuitive; objectively we would expect a runner to whittle down their 5k time from, say, 15:50 to 15:45, 15:40... 14:30. Instead we watch this hypothetical individual race for a year in the 15:30-15:50 range, then rather suddenly achieve a new PB of 15:10. They will likely hold this new time (plus or minus a dozen seconds) for another season. It is likely they will wonder aloud from where this sudden jump emerged. I have only truly experienced this jump once: for five years I ran 10ks in the 36-37 minute range, then after one season of serious training I was consistently in the 32-33 minute range for the next five years thereafter (here are all of my times since the late 90s; check out the jump from 2006 to 2007).

The reasons that runners must continue to run high mileage are complex, but the evidence is clearly compelling that it works. One good justification of performing high mileage is the counter-balance it provides to the inefficient state of racing paces. The strongest indicator comes from our nervous system's apparent need for very low-intensity, high-volume input. This need for volume is understandable since too small an input will be ignored by your body (would your body really be designed to start sprouting huge muscles after one visit to the gym?). Your body fat, VO2 max levels, and running technique are all byproducts of simple inputs that can be sustained for long periods (for instance your fat levels have surprisingly little to do with how much you eat and more to do with how your body regulates food input based on activity levels; and recall no healthy athlete is without a few pounds of fat). But to 'survive' this high mileage (and to save your nine injury-lives) you must stay efficient and relaxed as often as possible. High-intensity running is by definition impossible to sustain, yet I argue here only slightly different in pace from normal running (I argued before that we don't actually vary our speed by very much between jogging and racing).

Therefore efficiency does have a place in your race preparations, but perhaps not where you expected to find it. It may therefore be an acceptable conclusion that 'fast' running is just a slight deviation -albeit an inefficient and taxing one- compared to 'slow' running and therein lies the true 'secret' to success.

I hope some of these ideas help to bridge the mental gaps between the objectives of easy versus intense running.

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