It don't mean a thing/if it aint got that (arm)swing#

Tue, 11 Apr 2006 13:00:00 +0000

Bill Begg was in town today, so various LSST people organised an impromptu demonstration/coaching session. I may write that up properly later, but in the meantime be it known that he has six basic principles, and the fifth is armswing. Armswing According To Begg:

• approximately forward/backward motion (I think I've said this before somewhere). Some degree of lateral motion is needed, but not so much that the upper body twists. Bill described it as "more than a quad skater, less than an ice skater"
• the arm fully extended when behind the body
• bending at the elbow as the arm crosses the body, so that the hand ends up somewhere in front of the chest at the end of its travel. Should not be so high as to sock oneself on the chin, nor so much lateral movement that it's crossed outside the body on the other side. Frankly this is easier to explain with a demonstration or picture than in words, so please go and find a picture. Or a demonstrator.
• the arms "drive" the legs (metaphorically speaking: this isn't supposed to imply some kind of mechanical linkage). A too-short armswing will tend to mean that the push was also too short. Hence the importance of having some lateral swing - you can't get the arm very high up behind you without it unless you have really weird shoulders.

(When visualising this it helps to remember that when practising it you will be in skating position (i.e. bent) not vertical. Until I remembered this I was having doubts about the range of motion in my shoulders.)

Armswing According To Dan is presently a much more low-key affair: I don't. There's some kind of wacko historical justification for this that honestly isn't that interesting, and prompted by Bill's explanation - that and the sight of a very-nearly-empty Serpentine Road - I decided it really was about time I got to grips with it if I ever want to be able to accelerate. So, practice ensued, and now I think that provided I'm pushing hard while I wave the arms around I've found a swing that (a) feels like it's adding to my speed (this is rare and novel, having happened to me only once before) and (b) doesn't get competely out of sync with my legs in under four strokes. Whether it's correct According To Bill we will have to wait for some future video analysis to find out.

Whether it helps is yet another question, though empirical evidence (there are people faster than me who do it) suggests it seems to in practice. How it helps is perhaps the more interesting question, then. Note to the "unlock the power of gravity" people: there's no net gain on the action-reaction principle from throwing your arm away from your body behind you. Unless you sever it while doing so, sooner or later it will reach the end of its travel and have to be brought back. So, we're probably looking for some mechanism that makes it sufficiently worthwhile to get that extra oomph at a certain part of the push that losing it again at some other part of the cycle is a price worth paying.