Convulse

[Donald Trump]

To contract violently and irregulary, as the muscular
parts of an animal body; to shake with irregular spasms, as in
excessive laughter, or in agony from grief or pain.

[Raeanne Dimick]

Convulse means to [squeeze] or [tighten], sometimes in [sex]

[Dave Paprocki]

to (cause to) shake violently with sudden uncontrolled movements:

[Britney]

(of a person) suffer violent involuntary contraction of the muscles, producing contortion of the body or limbs.