I think Ian McKellen and Patrick Stewart did something similar in Waiting for Godot.
You want difficult? The role of Joseph (John) Merrick in Bernard Pomerantz’ The Elephant Man requires the actor to spend virtually the whole play in unnatural positions to suggest Merrick’s deformity. The published edition of the play comes with a warning against adopting those poses for extended periods of time lest the actor incur serious damage. It’s suggested that they work with a doctor to figure out how to perform with minimum harm.
As one actor recalled:
Or consider the roles Michael Crawford played. He did The Phantom of the Opera with half his face under pretty impressive makeup, and had to sing under that and perform physical feats. And do it every night. For Barnum, where he played Phineas Taylor Barnum, he walked around the freakin’ stage on stilts!