I’ve had a couple requests for this topic. This is a fair bit more complex than anything I’ve covered in this column so far, but it’s also really cool stuff – hopefully I’ll be able to do the subject justice.
Twisting serves two purposes in upper-level routines. First and most obviously, twisting adds value to skills. For female gymnasts, a back layout is an A, but by adding a ½ or 1/1 twist, the gymnast can increase that value to a B. A back 3/2 or 2/1 is a C, 5/2 is a D, and so on (for male gymnasts a back layout is already a B, but the rest of those values are identical).
The second purpose is to allow the gymnast to more easily spot the landing. While it seems counterintuitive, there are some instances where twisting makes a skill easier to land consistently. One excellent example is in a Tsukahara on vault (performed here by its inventor, Mitsuo Tsukahara). A Tsuk, while not that difficult to rotate, is extremely difficult to stick, because the gymnast cannot see the landing until the last half-salto. At this point, the gymnast is rotating extremely fast, giving him a good deal less than half a second to see the landing and react. However, if the gymnast performs a Tsuk 1/1 or Kazamatsu (two similar but distinct twisting Tsuk variations – a Kaz can be seen here), he is able to spot the landing right around the beginning of the postflight salto, giving him much more time to judge his height and rotation and prepare to land. Therefore, while a Tsuk 1/1 or Kazamatsu takes longer to learn, it is for most gymnasts easier to stick once learned.
So how does twisting actually work?
First, a couple of terms:
TRANSVERSE AXIS: The axis of rotation runing perpendicular to the body’s length. Saltos rotate about this axis.
LONGITUDINAL AXIS: The axis of rotation runing through the body’s length. Twists rotate about this axis.
ANGULAR MOMENTUM: This is the amount of “rotating power” a gymnast has while airborn.
With that out of the way, let’s look at ways in which twist can be generated.
- 1. TORQUE: This is where a gymnast begins to turn his upper-body before breaking contact with the floor.
2. OPPOSING ROTARY MOTION: This is a bit more complex, as it involves twisting without any net change in angular momentum about the axis. Without any external force, rotating any part of it in one direction causes the rest of the body to rotate in the opposite direction. This is why helicopters have a sideways rotor on the tail; without a tail rotor, the body of a helicopter will spin in the direction opposite the rotation of the blades on top. A gymnast can use this principal to twist by performing a hula-like motion with the hips in one direction, resulting in longitudinal axis rotation in the opposite direction. This is the principle a cat uses to rotate to its feet when it falls form a high place.
3. BORROWING VIA TILT: If a gymnast is performing a salto, she already has a fair amount of angular momentum about the transverse axis. By the use of asymmetrical arm movements (ie moving an arm up on one side of the body while moving the other arm down on the opposite side of the body), she can cause her body to tilt slightly off-axis. This causes some of the angular momentum about the transverse axis to be “borrowed” to rotate about the longitudinal axis.
Coaches tend to discourage gymnasts from using torque or opposing rotary motion to twist, because both tend to interfere with other aspects of the gymnasts’ technique. A gymnast who tries to torque on takeoff will often end up sacrificing proper set technique on the salto, resulting in a low and often-underrotated salto. Similarly, a gymnast who deliberately uses opposing rotary motion to twist will be forced into a continual hula-mtion, which often makes the salto very difficult to control, and also just looks sloppy. A gymnast who twists by tilting, however, can generate twist while airborn, maintain the same body position throughout the twist, and completely stop the twist before landing. These three things make tilt the preferred focus of gymnasts learning to twist. In reality, there are a few occasions in which gymnasts must supplement their rotation with a bit of torque or opposing rotary motion, but we as coaches tend not to deliberately teach this – it tends to happen on its own anyway.
There is much more nuance to be discussed concerning twisting, and I’ve only scraped the surface. If anybody has any further questions about twisting (or anything else), feel free to ask.