I'm pretty sure I've made that face straining on the toilet before.
Aerobatic Pilot’s Facial Expressions During G-Force Maneuvers

This is a video of Polish aerobatic pilot Artur Kielak performing during an airshow with a camera facing towards him to capture his facial expressions during extreme g-force maneuvers. As someone who gets motion sick just walking, I couldn’t imagine being able to do this and not passing out, crashing, and dying. Heck, I once passed out on a roller coaster at Disney World and when I finally came to we were already home, the vacation long over. I think I missed a birthday too.

Keep going for the video, but be sure to skip around to the parts with his sunglasses off for the best bits.