Put strength to all your muscles

[Summary]
You can rotate faster when you put strength to throughout the body because your body become tight single object.
Conversely, surprised by new feeling in the air and loosen your muscles and then you get slow rotation.

You must complete changing your form faster and fix your form and put strength.
Especially just after taking off, your body get loose and rotation can dissipate away easily.
Not to let rotation decrease, you should put strength to your whole body as soon as possible. (Especially, in backflip, you jump with your back muscle contracted so your abdominal muscle is loosen.)

[Details and Theory]

-A PET bottle with water in it doesn’t rotate well-

It is difficult to rotate a PET bottle with water in it ,since the water scatters to various direction.
But you can rotate that PET bottle easily if the water is iced, because PET bottle and the water is single tight object.
Also, if the bottle is filled with water, because water cannot move so much, it becomes easy to rotate.
Even if the bottle becomes heavier, it get more efficiency for rotation.

The same thing is affirmed about the human body. When rotate or do some other action, you can act easily if your body is tight and force is easy to be conducted.
Altough it is difficult to run with a backpack since movement of our body and the backpack are deviated, you can easily run with the backpack with the backpack tighten to your body.
On the contrary, a long jumper thrashes their arms and legs about not to be single tight object in order not to rotate and not to make their record shorten.

While changing posture, the muscle which acts to the opposite direction of the direction the muscle contributing to changing the posture. (For example, when you bend your elbow, your biceps is tighten and triceps is loosen.)
Therefore in the meantime our body is difficult to rotate.
How does becoming single tight object contribute to rotation.

– Pull a dog to make it rotating around you-

A part of a rotating object has speed in the direction of tangent of that part.

How does an object rotate which has only the speed in the direction of its tangent.
It properly rotates due to the force pulling the object to the center of the rotation. In the example above, tension of the thread is that force.
Assume that you rotate your dog around you which walks only straight way.

Your dog walks in the straight way and goes away from you little by little. However, if you pull your dog to you little and change the direction the dog walks in, the dog maintains a certain distance from you.

In the air, you make your dogs which are everywhere in your body rotate around you by pulling these with your muscles.