Exercises (in my little universe, of which I am the center) are to perk up your muscles and make you aware of them. And hopefully you will then utilize them more every moment of your day.

You can go to the best exercise class in town, but if you climb into your car afterwards and slouch down in the seat for the drive home, stand with locked knees and dropped chest while you cook dinner, then slump in front of your computer for a few hours, then sag in the couch to watch a movie before bed.... well, what have you changed?

My favorite exercises for core and posture are the prone and side planks. They are just "good posture" turned on its face or side. If I take a picture of someone and cut away all the background, I shouldn't be able to tell if they are standing up, in a prone plank, or in a side plank. It should all be the same neutral spine and good posture. Switching the orientation of the body to gravity mixes things up a little and makes posture spicy! (painful, hot, and sweaty)