Selasa, 30 November 2010
This was the photo I had in my head as I was running the Marathon the other day. The question is: which of the two runners above has the better technique? (Hint: they are both Ironman or Half Ironman World Champions so they are probably running at about 18kph in the photo.)
When I got back into running recently, I was surprised that no-one talked much about running technique in running magazines. Having been a keen rower in my teens and early twenties, I knew how important technique was. Of course, in water sports the resistance is 1,000 times that of air, but even cyclists are well known for their obsession with pedaling technique and posture. It seems as though the only reason is that running is considered to be a "natural" activity (whatever that means) and therefore we are all born with perfect technique. Actually, that's not as silly as it might sound: if you have ever watched small children running, you'll have seen some of the best running technique on the planet. On the other hand, if you have ever run a Marathon, you'll have had a chance to marvel at the extraordinary variety of running styles, not all of which can possibly be considered good technique.
So what happens to screw up our running style? Wearing shoes, that's what.
OK, OK, I know that there has been a lot of hype lately about barefoot running and I really don't want to get into that. (Having sustained a stress fracture in my foot from running too much, too soon in too minimal a shoe, I know the dangers.) However, shoes have been getting ever more bulkier as new materials are developed to allow them to maintain a reasonable weight. The more padding, the higher the heel counter, which means more and more stability features have to be built in as your foot is raised further from the ground. There are two negative side effects to this tendency (apart from the escalating price, that is):
- The stability features take protaganism away from the many muscles in the feet and lower leg that are designed to keep you upright and, as a result, the muscles and tendons weaken (atrophy).
- The extra padding reduces the sensitivity of the feet. If you've ever had your feet tickled, you won't be surprised to know that your feet are especially sensitive: the sensors are there to "automatically" activate the orchestra of muscles in your legs and core as your feet touch the ground, so that you don't fall over. It's something that happens so quickly that there isn't time for the message to be processed by the conscious part of the brain. This is called "proprioception".
These two side effects are viscous circles: the weaker the muscles and tendons become, the more stability you need. The more padding you have, the harder you land (your leg muscles are activated imperceptibly later) and the more cushioning you need. There is also a third feedback loop: more padding encourages you to land on your heel - there is a theory that the lower perceived impact of the foot tricks the body into a walking gait. Heel striking exaggerates the rotation of the foot as you land and requires more stability. This rotation is called "pronation". In fact, this was the alarm bell that rang when I got back into running. I'd run for many years without any problems or ever having heard the word "pronation" before. When I got back into running, my knees started to hurt and I was immediately told I needed orthotics and shoes with extra stability control. Lo and behold, the knee pain disappeared overnight. The problem is that this is rather like prescribing someone with a limp crutches for the rest of their life: their limp may get better but they will be dependent on crutches for life AND more susceptible to further injuries due to weakened musculature. (There are scientific studies out there on the incidence of injuries with motion control running shoes if you look hard enough,)
The other thing that caught my attention was the fact that I was strongly recommended NOT to buy lightweight running shoes or "racing flats" because, at 90 kilos, I weighed too much. As I am a bit of a bloody minded sort of person, this just made me want them even more. I realized that an elite slip of a runner would be hitting the ground with a far greater impact than me because, at more than 20kp/h, the ground forces are much higher than at my more humble speed, even if I am carrying an extra 30 kilos.
I don't want to get into a long discussion of running technique either, but I will give you some pointers in case you are interested. There are several schools out there, all with very similar approaches. As usual, the key is in the subtle differences between them. To name the most prevalent ones there is Evolution Running, The Pose Method, Chi Running, Natural Running,... I can only comment on my own, personal experience and that is that I found the Chi Running book too "mystical" although it was the first time I realized the importance of the core muscles in running; the Pose Method, however, is based on much more hard science and so it particularly appealed to me. What is also different about the Pose Method is that it is, as its name lays plain, a method which is something more than a technique - it is also as much about how you learn that technique. For me, it has two key innovations that distinguish it from the others. Firstly, the charismatic Dr Romanov makes a big deal about concentrating on taking your foot off the ground rather than on how you land. The idea is that you cannot effectively control how you land directly as this is taken care of by proprioception (and, if you try, you'll only tense up and waste more energy / injure yourself). However, as you are flying through the air, whatever you do with your trailing foot is reflected by your leading foot otherwise you would not be in balance. The second innovation is the focus he puts on perception. When I first read the book, I thought this was more mystical mumbo jumbo but I had a chance to experience it first hand when I went on a Pose workshop in Denmark last year with the very same Dr Romanov. We were filmed running, we did some drills and we were filmed running a second time. Everybody improved on the second video but I was sure that I would not have done as I had made no conscious effort to change anything the second time I ran. I was flabbergasted to see that I too, had made a measurable improvement in the second video. The reason: the drills taught my body to be more aware or to perceive important aspects of the running technique.
What the various techniques all have in common is that one should try to reduce the "bounce" in the run as much as possible. If you think about it, as we are running along horizontally, we are doing work against gravity by bobbing up and down. It seems counter-intuitive, but the main way to achieve this is to take shorter strides or, equivalently, run with a higher cadence. Personally, I think it is better to increase your cadence as a result of running correctly (e.g., not heel striking nor over-extending the trailing leg, having a compact arm swing, etc.) rather than to force it by running with a metronome(!) for example. The other benefit of not bouncing is - you guessed it - you land with less impact and are much less likely to sustain injuries.
I should warn you that it takes about a year for all your muscles, tendons, bones and ligaments to "reconfigure" for a new running gait - I learned this from painful experience (in the literal sense). The Pose book actually says that you should only run as long as you are able to run well so that you have to have a lot of patience to learn the new technique, running perhaps 5 minutes only and making up the rest of your training with some other exercise. If you follow any of the above mentioned techniques, you'll end up using your Achilles tendon and your calf muscles much more than before, and your knees much less as the load is shared over the whole of your leg. A good way to know if you are running too long with the new technique is if you have any pain in your calf muscles the next day. I have finally accepted that PAIN IS BAD.