Not having a chair back means my muscles have to work to keep my back upright: there's no way to slouch backwards. Correctly postured, that work is minimal, bu

Not having a chair back means my muscles have to work to keep my back upright: there's no way to slouch backwards. Correctly postured, that work is minimal, but keeps the muscles working and healthy. A chair back with lumbar support prevents you from sitting in a bad posture, but doesn't help develop the muscles that naturally promote good posture. Even better would be if I could get rid of my desk so I have no way to slouch forward.