Runing away to join the Circus#

Thu, 04 Jan 2007 16:41:18 +0000

One of last year's New Year resolutions I never got as far as: I'm now booked in for the Circus Space whole-day workshop in February. Should be fun.

I'll come back in a bit and fill in some of the gaps left by Christmas. Not a lot of skating in any way shape or form, it has to be admitted: I got a cold the week before and I'm still not 100% - at least, every time I blow my nose blood comes out of it, and I'm reasonably sure that's not entirely normal.

They also serve, who only stand with weights#

Fri, 05 Jan 2007 15:48:44 +0000

The chief attraction of weights so far is that I can do it inside when it's wet out. Observations made so far are

Legs:

• I don't have enough weight for two-legged squats
• If I were better balanced I wouldn't really have enough weight even for one-legged squats, but the wobble adds an extra challenge to it.
• The noise from my knee is disconcerting
• but appears to be unconnected to the pain in my knee which develops if I squat (on however many legs) without warming it up thoroughly - and I mean ten-minutes-running-on-the-spot thoroughly
• That last seems to be less of an issue than it was when I started, so I may be strengthening my knees this way even if I'm not able to push my quads/glutes to failure
• It's very easy to do too much. "Too much" is here defined as "still feeling it two days later"

Summary: I believe I'm developing some knee strength, but there's not yet much evidence that I'm getting any actual go-faster-muscle bulk. Too many reps, not enough mass for that, but anyway I can't do that until the knees can cope.

Arms/upper body:

• really only doing these because I'd quite like an upper body. Not expected to help with skating, unless perhaps that when I take a dive forwards onto my hands they may make it less likely I spread the load onto lower face and teeth
• dumbbell "bench" presses on a swiss ball are a great core exercise
• but way easier than the fly
• am unwilling to exercise to failure, because I'm doing it on my own and don't like the idea of being knocked out by my own dumbbell when it falls from my limp rubbery hand. But can exercise to "really don't feel I can hold this any more" and still not hurting the following day. Odd

If you know as much now as I did a month ago about this stuff, Wikipedia has pictures

Weighting for the other shoe#

Mon, 08 Jan 2007 20:55:22 +0000

But can exercise to “really don’t feel I can hold this any more” and still not hurting the following day. Odd

That last was written before I'd waited two days after first trying the dumbell chest fly. Ow. Less odd.

First skate 2007#

Wed, 10 Jan 2007 23:39:49 +0000

Last night was the route check for the first LFNS of the year, and also the first time I've skated this year not counting commuting. And it was oh so much fun. Bounce bounce bounce.

Armswing#

Tue, 16 Jan 2007 14:08:54 +0000

Being a summary of the effective speedskating armswing, and some flailing around to attempt to explain how it works. Let's start with the conclusion.

• An effective skating armswing is approximately front to back. The arm at its foremost position should have bent elbow and hand somewhere in front of nose: it then travels backwards and outwards until the arm is stretched out straight somewhere behind you

• there should not be so much lateral movement that the shoulders rotate: this is tiring and doesn't achieve much

• the arm should brush the torso as it passes

• swinging arms faster will tend to make the legs go faster (this is often stated as "the arms drive the legs") - good for starts, accelerations, anything else where change of cadence is required

• swinging arms whn you don't need to is tiring.

• armswing on uphills may be a bit more lateral (but the shoulders caveat still applies)

This much is standard, and empirically we know it works, but the interesting question is "why?". If you disagree with the conclusion you are unlikely to be interested in the speculation which now follows.

Let's get the standard rant out of the way first: Newton's Third Law won't help. Over the course of a whole stride, throwing your arms in one direction will not make you go faster in the other direction unless in doing so you sever them. Otherwise, you have to bring them back towards you: the negation of the move you previously made, which at that time will make you go slower in the other direction.

Then what? A simple mechanical explanation, also, does not suffice. We are swinging our arms with a largely fore-aft motion apparently to counterbalance a lateral motion in the legs? Does not compute. I have speculated in the past that the small lateral component helps somewhat, and indeed it must have some kind of effect, but if that was all there is to it then a casual gentle armswing would be just as effective as a full-on sprint armswing - after all, the lateral motion is more or less the same - and we know that's not the case. It also doesn't explain the connection between armswing speed and leg cadence.

So I think we have to look at THE BRAIN. And the supposition is that as we evolved from quadrapeds we have vestigial stuff in our neural system to enable four-legged locomotion without falling over: specifically, that the timing and power used in a foreleg stride will affect and be affected by the timing and power in a hind leg stride. So when your front feet - er, arms - break into a trot, your back feet will follow.

One possible mechanism for this is the Central pattern generator - neural networks in the spnal cord that produce "rhythmic patterned outputs". They control the flight of the locust and the wiggle of the lamprey, and are claimed to be present in humans too. Another is good old-fashioned muscle memory - which basically says that if you practice it for long enough you can eventually stop thinking about it (in the cerebellum) and rely on your motor cortex to fire the right signals at the right time. Not being any kind of expert I don't know which is right, but I prefer the first explanation because it's cooler. Neural networks in our spinal columns Zombies! Er, ahem.

Anyway, that's basically it. The three most important things about armswing, in my book, are

1. don't swing side-to-side, it makes you look like a gumbie
2. swing faster to accelerate
3. armswing during crossovers makes foot placement a whole lot simpler. But that may be a topic for another time

Lost bearings#

Tue, 16 Jan 2007 20:08:33 +0000

These all-weather (to be more accurate, only "most weather so far") outings are not kind to the mechanical bits. I'm running with greased bearings and I don't care too much how fast they spin as long as they're still going round, but that one was notchier than a small stepper motor.

Went for what was supposed to be an LSS last night: laps of Regents Park outer circle. Frankly it was distinctly uninspiring: the road is dark, the surface is rough, the drizzle makes the bits that aren't rough slippery, and the wind was against me whenever I noticed it. Did three laps in about 11 minutes each (which I think was too fast, but when it's that tedious you don't want to hang around) before deciding "blow this for a game of soldiers" and heading home. Home via an elaborate route (still trying to find good bits for my LFNS next month) including a couple of roads I hadn't seen before, then when I arrived on Kingsland Road pointing in utterly the wrong direction (see post title, above) an unscheduled excursion northwards to Kingsland. In the end this was as much distance covered as I managed in the original exercise. And much more fun.

Also lately: (1) commuting, (2) rode the Bassfreight on the LFNS

Crunchie#

Fri, 19 Jan 2007 16:00:39 +0000

Eating chocolate more dangerous than skating, new study shows.

That's right. I went out for a skate at lunchtime, jsut to make sure I know where I'm going on the LFNS tonight. I skated through the twig drifts in Battersea Park without stacking, I stayed upright through the diesel patch on the corner at Grosvenor Place. I got back to the office for lunch, and after a couple of minutes I was thinking "this Crunchie bar has some really crunchy bits". Nope, not in fact golden honeycomb caramel whatever it is, but a large lump of dental composite that has come detached from the tooth it's been sitting on since September.

Dentist appointment set for Tuesday. Gnngh.

Nice skate, though. Other skating this week: Monday night, as previously mentioned, and official LFNS RC on Wednesday.

Ton up#

Sun, 21 Jan 2007 18:42:13 +0000

Adding everything up, I've done a metric 100 this week (skated Monday, Wednesday and twice on Friday). Though it's nice to be properly back - week previous I did an RC and nothing else, week before that I don't think I skated at all - it seems to have been a surprise to my feet: raw patch on outside ankle bone left foot, and on back of ankle right foot. The former is easily explained as being due to excessive T-stopping (until I rotated that foot's wheels on Friday evening, the bevel was such that the frame was effectively off-centre). The other I'm not so sure about, but I think it may be related to possibly having sorted out my lop-sided push a bit (every time I've noticed it lately I seem to be getting a good carve on both sides - which is a step in the right direction, but what I'm doing the rest of the time, I dunno) and driven something else wonky in the process.

Two-arm swing still feels good and mostly unforced - still haven't actually seen it except in shadows, though - and I seem to be starting to crossover on right turns without thinking about it much. All told, I've had worse weeks.

Weekend off: weekend spent in furtherance of my undeclared new year resolution to make my flat human-habitable (though I'll happily settle for Dan-habitable as a second best, I'm not fussy). Saturday I inflicted an IKEA visit on myself (that thing you can see on the right: it's all my lycra together in one place for possibly the first time ever), and today has mostly been sitting in a coffee shop hacking. And writing blog entries.

Throw up#

Sun, 21 Jan 2007 18:55:52 +0000

I started writing something about javascript, but it rapidly became mind-blowingly tedious even to write, so I can see no reason that reading it would have been any more fun. Herewith the executive summary.

The task: rewrite the LFNS route editor/viewer so that I can actually understand what it's doing (and perhaps more importantly, what it should be doing but is failing to do)

Lessons learnt:

• Don't try to use inheritance to link loosely-coupled system (e.g. the Model and View in an MVC architecture), because the effect of javascript inheritance is to couple them tightly. A publish/subscribe event-based system (I'm using GEvent, just because it comes for free with the Maps API) is a much nicer fit for the language. Yes you can do inheritance. But trying to call the "superclass"(sic) method from your overridden method is enough work that you should get the hint the language wasn't really intended with that in mind. And you can forget CLOS-style interesting method combinations
• Don't write for (var a in myarray). Not if you want to use prototype.js anyway
• prototype.js is the stupidest name ever for a javascript library, because, guess what, the word "prototype" is already heavily used in javascript. Congratulations, anyone trying to google for assistance is basically screwed.
• while I'm thinking about Google: there are too many morons writing web pages about javascript, too many others linking to them, and my js googlefu is not yet sharp enough to devise search terms that won't pull up their retarded witterings.

All my wheels, in one basket