Jumat, 14 Oktober 2011

Keep those knees up boy

I've been thinking about what Jonathan told me about my running technique during the training camp in Morocco. The best thing to think while running is about running. Jonathan pointed out that there is a small pause in which my foot shoots out as if to kick a football just before I land slightly ahead of my center of gravity. He said that I should try to lift my leg up and forwards to get the foot in a better position for landing. I've been playing around with this while I've been running this week and the perception I have is very similar to one I had when I first started running POSE. I can only describe it as a feeling that I am preparing myself to sit down. I also notice that my foot tends to land flatter and the heel touches the ground very lightly. I feel that I am picking up the ground more quickly but the proof will be to film myself in slow motion while running. I now have several "cues" to think about while running:

- to extend the hips (or "punching it forwards" as I call it)
- to get my legs up under me ("sitting down on the job")
- to lean from my ankles ("run tall")
- to pick up the ground quickly ("sharp catch")

As you get tired you unconsciously cut these corners because you obtain an immediate energy reduction; however you end up going more slowly and you have less time to recover before the next step so it is a very short sighted strategy.

There is a big debate over which muscles we use while running. The POSE Method makes much of a study in which it was demonstrated with electrodes that the quadriceps cease to be activated once the mid-stance has been achieved (body in balance over point of contact of the foot) implying that there is no active push off in running. This is very counter-intuitive and, as Jonathan says, would suggest that runners are wasting their time doing so many squats in weight training. The POSE Method maintains that there is no active push off and that your foot should be lifted using your hamstrings and not your hip flexors. It's a pretty bold claim and it is what really separates the POSE Method from the other running schools that have popped up more recently. Does this mean that you should not extend your hips while running? What about the convention wisdom of lifting your knees? Should your foot fall "dead" or should you actively grab the ground as your run?

To my mind, this is all to do with the interplay between energy and momentum (I should really say between potential energy and kinetic energy, we think of energy in running as our cost and momentum as the consequence of expending it) and the difference between active muscle use and passive muscle use.

As Dr Romanov himself says, in order to measure how well someone runs, you must have an ideal to hold them to, even if it itself is unattainable. The POSE Method aspires to an infinitesimal contact time in which case it is clear that to position your foot to land under your center of gravity all you need to do is lift it up directly under your butt with the hamstrings. However, when we take our foot off the ground in the real world, we must overcome the angular momentum that we generated by leaning forward to gain forward propulsion in the first place. I have no scientific evidence to back this up but I believe that this means that we must use our hip flexors to stabilize the leg and that this accounts for our perception that we are lifting our leg up vertically when, in fact, it is lagging behind our body. Similarly, I think this accounts for my perception that I am "sitting down" while running when, in fact, my legs are not in front of my center of gravity (as they would be if I really was sitting down). This is similar to if you try leaning against a wall and then suddenly standing up straight: you feel like you are leaning in the opposite direction when you are actually perfectly upright. So, hamstrings or hip flexors? I believe that we should focus on actively using our hamstrings and on the perception we have when we are correctly landing under our center of gravity (passively using our hip flexors).

When we extend our hips (and stand up on tip toes, for that matter), I don't think of it as pushing off but rather translating potential energy from our elastic muscles back into momentum, like a spring extending as it bounces off the ground. In any case, what is the difference between pushing off and leaning forward? If you are standing still, the difference is that you may let gravity pull you forwards as soon as you are out of balance. When you are running, the forward momentum throws you out of balance as soon as you hit the ground. Again, it is another question of active versus passive muscle use.

If you let your foot fall dead then it will be moving forward with respect to the ground when it lands, causing a braking effect. In the POSE ideal of "zero contact time" we would be able to instantly accelerate the foot to ground speed on touchdown but, as this would require an infinite amount of energy, it wouldn't be terribly efficient even if we had the physiology to do so. The analogy in rowing is the "catch" when you put the oar in the water. Ideally it should be not moving with respect to the water at the instant it is placed in the water (you can tell if this is the case by checking that there is a symmetrical splash on either side of the blade). Matthew Pinsent once described this to me as it being like trying to catch and accelerate a spinning fly-wheel without braking or jarring it. One of the things I most like about the POSE Method - again, a concept that sets it apart from the others - is that the focus is on "take off" and not on "landing". I believe that you cannot effectively control how you land because it is something that must be exquisitely orchestrated by the proprioceptive system. In other words, I believe that the landing should be passive but that we should focus on the perception of picking up the ground quickly ("sharp catch").

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