Working overtime

I went through this a few days ago — a day full of online meetings. I just got a new set of headphones, and I had to wear a face covering because there were too many people in the office. When I went home I noticed that my ears were worn out and tired. Not like after a concert, but like they'd been carrying extra stuff all day. What a weird feeling! 

I wonder if there are exercised one can do to build up one's ear muscles?