New job, new chair

I started a new job today! I'm a teacher no more. There are so many details to ponder, but one moment that particularly stands out is when I saw my new desk chair.
I could practically hear myself trying to explain it to my mom. "You're sitting on an exercise ball at work??"

Supposedly they are supposed to be great for strengthening your back and core. Well, today I found out that I may not have neither lower back nor core strength. I was definitely sore! I'm looking forward to my newly toned self that will inevitably show up to work tomorrow.