What is the seemingly simple move you can just NEVER do?

Just curious because I always wonder about other people – what is the very simple move that you can just not do? For me, it’s the side plank!

Every time I’m in a strength class and they say go ahead and hold a 45 second side plank or something, I’m just sitting there, mouth open wondering how the hell am I gonna hold for 45 seconds one of those on each side? Seems like it would be quite easy, but it always kills me! I’ve been working out for years and for some reason, they just never got easier.

Honorable (not so honorable) mention to the bear planks with the LEG EXTENSION?! Sorry Katie Wang- I’m not Superman, I’ll be over here doing a dead bug.