Tuesday, March 6, 2007

It's All About the Sweet Spot (and some symmetry)


My last competition in my pre-Vicious Momma days. I was 27 and got pregnant with my first child about a month later. The top right photo is a "flying camel" in midair. Below that is a split jump, and the other two are just interpretive moves to the music ("I Need A Man" by the Eurythmics, lol). For comparative purposes here is a photo of Dick Button midair in a flying camel. You can see the difference between an Olympic champion and a recreational skater:




I haven't read any of the articles found on Google about this because I just want to say what I'm thinking about it first. And I'm sure some of those other articles are much more technically adept.

Figure skating could be a kind of real life analogy to some of the problems of theoretical physics. What I mean is that advanced skating requires probably as many considerations to successfully execute a trick as it takes calculations to get to a final answer.


(slightly exaggerated "hollow")

The blade is concave along the bottom (the "hollow") such that there are two sharp edges, and the blade is also not flat longways.



It is slightly curved, sometimes referred to as the "blade rocker." When learning to skate you learn the "sweet spots" on the blade that make jumping and spinning easier and more 'efficient'.



If I were a real physicist I might know how to calculate the speed and curvature of the blade and so on to describe the various jumps and to explain why the "sweet spots" make them easier, but this is one situation where being able to make the calculations on paper doesn't necessarily help you execute the tricks on ice. It is a much more intuitive process that allows you to feel the sweet spots.

Back in the "old" days we still did compulsory figures, or "figure eights." These exercises were ultimately intended to teach and train skaters how to 'finesse' their blades and bodies to perform precision turns and tracings on the ice. We learned how to make slight adjustments in our posture, shoulders, hips, arms, legs, heads, feet, and even toes so that the blades moved through turns in the most "perfect" ways. For example, a "3 turn" when done just right should leave a tracing a like this (below), note the gap at the top which shows the shift from one edge to the other while changing direction (forward to backward or backward to forward).

Another example is a "bracket," a more advanced turn which done right looks like this (above), notice the "rabbit ears" which indicate the change from one edge to the other while also changing directions.

And yet two other advanced turns are the "counter" and the "rocker" which are closely related to the three turn and bracket but in instead of changing edges you change "lobes" on the figure eight and direction but stay on the same edge.



In order to perform these turns and to 'retrace' them we had to learn the sweet spot on the blade and learn how to repeat all the factors that created it. Incidentally, figures blades don't have the bottom toe pick like freestyle blades, and that increases the "rocker" length and how much you can manipulate the blade. This took hours of practice, but I always loved doing figures because it appealed to my detail and perfectionist nature.

Also, perfectly executed turns are supposed to be symmetical. In fact, skating is where I first heard the word "symmetry." I won't tell you how many drawings it took to get close enough to symmetrical in the above illustrations, but it was more than I planned on. If it is hard to draw a nice 3 turn on paper, then just imagine how hard it is to do it with your feet and a blade on the ice!

Most of my skating teachers didn't pay any attention to the tracings of jumps and spins, but I was lucky enough that my last teacher used these tracings as a tool to evaluate jumping and spinning technique. All skaters should learn such things! We referred to this as "physics" of skating, but I really don't know if that is an accurate description. However, it most certainly helped my technique to "read" the tracings and therefore see how the errors in them tranlated into errors in my body position, etc. If your tracings are correct then your trick (jump or spin) will most likely succeed and be good.

There are many skaters at the highest competitive levels who could really benefit from this kind of instruction. Maybe these days it is more common than when I was growing up. I don't know. But I sure do see some very sloppy technique on TV that is most likely a symptom of focusing on the wrong body parts, instead of the feet which are the ones closest to the ice. The best skating is in the feet. Chances are if your feet are doing the right thing the rest of your body will follow, though there are some exceptions and you can't exactly separate the feet and the body and how they interact.

Anyway, skating is probably one of the most beautiful, and technically complex, expressions of the laws of physics in motion. I wish I was clever and smart enough to make deeper analogies about it.

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