Diva flex
Flexing one's muscles either literally or figuretively . Seems to be a practice common amongst celebrities of various ilks and persuasions.
1 Rhonda rowsey performed her diva flex by showing off her biceps just before the boxing match. 2 sly stallone did. His diva flex by arriving to the set in a golf cart and insisting that none of the crew look him in the eye or speak directly to him.