Lately I've been finding it so comfortable to have my arms raised over my head. I don't know what muscles it's stretching, but it feels so great.
I think I kow why this is lately so comfortable. When I work as the t-shirt wench for Canada Rocks!, I'm on my feet for more than an hour before the show starts and then another half hour during intermission and after the show lets out. The floor is concrete. This is my thrice weekly routine.
At the Confederation Centre of the Arts, they (try to) train the staff to pay attention to every detail that they are projecting to the guests (i.e. money sacks). Therefore, our body language has been strutinized. Smiley smile. Don't point with one finger. No crossed arms. When we are standing still, we are to have out arms hung at our sides or clasped behind our backs. This is a non-threatening pose. Crossed arms are defensive. And oh so comfortable.
So, when I stand for such a long time in the lobby, smiling at guests (i.e. money sacks), I clasp my hands at the small of my back. This pulls my upper arms and shoulders in an unnattural position for long periods of time, and the muscles get tired. It also thrusts forward the girls, and I'm not complaining about that.
Usually about twice a week, there are too few workers in the theatre, so once the show begins, I switch over from t-shirt wench into usher mode, and sit inside watching the audience. At the back of the house, in the dark, I love to extend my arms straight up over my head. I don't necessarily stretch my arms over my head, but just hold them there.
I think it's cool that my body will naturally take the position that relieves the unnatural position I force it into.