My physiotherapist has told me that slouching for 20 years was the main cause of my shoulder injury last year, and that I had to stand up straight from now on, and only lift a weight if my shoulders were back.
After a few months, when the pain was gone, she discharged me and said to take up swimming. Having got into the water, I did the only stroke I know - breaststroke - and realised that I was spending 90% of the time with my shoulders rounded forwards (i.e. not back as I was told to!). I worried this might be unhelpful. My shoulders are only being pulled back briefly as my hands touch and my head emerges to inhale.
My question is: Is it correct that the shoulders should spend most of the time extended forwards during breast stroke?
I've hunted the slow-motion YouTube videos but they don't happen to mention this specific point, probably because most people don't care.