How exactly does torque apply to gymnastics?

[Sundown444]

Well, if I have this down correctly, torque is equal to force times distance of the lever arm. The more force or the longer the lever arm, the more torque something has. If that is true, how can you apply that to gymnastics, mainly somersaults, cartwheels, flips, spins and the like?

 

[Fewmet]

You can say that applying a given force someone's head will apply a greater torque and cause a greater rotational acceleration that applying it to, say, the chest, That, though, does not seem like a realistic scenario in gymnastics.

I think the more interesting case considers rotational momentum, which is rotational inertia multiplied by rotational speed. Since rotational inertia depends on mass distribution, "tucking in" while rolling reduces rotational inertia and so increases rotational speed (because rotational momentum is conserved). You spin faster when you curl up and slow down when you spread out.

I think I first considered this learning Aikido. When I want to stop a roll quickly, I uncurl and my rotational rotational reduces (and the floor applies an opposing torque to my arms and legs. Another aspect is that being tall provide a greater lever arm for an opponent and can be easier to know down.

 

[CWatters]

Somersaults usually rely on conservation of angular momentum. For example by rotating your arms in one direction your body rotates in the other direction so the net change in angular momentum is zero.

But it's also possible to gain angular momentum by interacting with the floor or vaulting horse via friction.

 

[CWatters]

If you are learning about forces and torques it might help to compare the equations for linear and rotational motion...

Force = mass * acceleration
Torque = moment of inertia * angular acceleration

Power = force * velocity
Power = torque * angular velocity

Can you see the similarity?