Wow – I think I’m finally beginning to understand a bit about sine wave. Sure, I’ve got the basic bit about down-up-down and I’ve understood that sinewave is part of coordinated action so that within a technique, everything ends at the same time, but I hadn’t really considered the role of sinewave in coordinating with other people or coordinating sequences of movement.
When we spar, we are always encouraged to keep moving, to keep bouncing on the balls of our feet, and all good fighters in all forms of fighting keep moving even when they aren’t actually punching or kicking. Maybe it is obvious to everyone else, but I have only just realised that the bouncing is part of sinewave, and the rhythm provides an internal beat for planning and coordinating sequences of movements. More importantly, you can speed up or slow down the beat and still execute the same sequence of movements. When you are watching your opponent, you’re not only watching them with your eyes, but you are entraining the rhythm of your bouncing to the rhythm of their movements (ie you are mirroring their timing so that you know when they will be able to execute a technique). You can then set an appropriate phase lag between your sinewave and theirs so as to time your own techniques for when your opponent is unable to respond.
So when are they unable to respond? If you know by understanding your opponent’s rhythm when they are capable of executing a technique, whether or not they do, you can adjust your sinewave (bouncing) so that your techniques will only show themselves when your opponent is already committed to whatever they were going to execute (they have already selected a ballistic movement to a specific target) or they are not yet ready to attack (they have missed that wave of their own sinewave). You will have so much more time in “planning” because you have already encoded the relative timing information between their actions and yours into your own sinewave or bouncing rhythm.
Adjusting the frequency of your bouncing (your sinewave) to encode your opponent’s movement, and adjusting your own movements to fit into that rhythm also cuts down on planning. A jumping kick is no longer different in its premotor planning to the same technique on the ground – the jump is part of the sinewave, but the wave just goes a bit higher 🙂
So – the bit that started to fall into place was that bouncing (keeping moving) in sparring is not just random moving, and not just keeping a rhythm for yourself, but it is a part of a “conversation” with your opponent to keep the appropriate timing and phase relationship between your movements and theirs, so that you always have the advantage. If you are sparring with someone who understands this conversation, the trick is to be able to change the tempo to keep the advantage.
The reason that skipping is the preferred endurance training for fighters is also an obvious correlate of sinewave. The circular motion (sine wave is a circular function in mathematical terms) of the rope powered by your arms ensures that you have to entrain your arm movements to you leg movements and you have to jump. The cyclical visual cues of the rope are also being entrained so that you can start to associate visual information with motor information. The “conversational” aspect of skipping – the entrainment to the visual cue – can be seen when someone else turns the rope. If you watch kids run in to skip in an already turning skipping rope, they move their arms or bodies up and down for a few cycles to get the rhythm of the motion. There is an easy side and a hard side to run into because on one side, there is room for error (the rope is coming down so you can duck) whereas on the other side, the rope is going up so there is no room for error.