I have been working to improve my posture as a result of a life of slouching as well changing to standing workstations. I find that when I use good posture that breathing, especially while exercising, and working become easier. The hard part is working on posture as it begins to work unused muscles and takes more effort than I had expected.
Then I found that not even what I thought was good posture practices were obvious from this Infographic. It helped with some information about what to do and not do while at my desk.