We had a good, brief post on posture last week.
It is indeed true that our posture, along with our general comportment, attire, manners, speech, and capacity for chat are what others base their initial impressions on. Rightly or wrongly, those things matter to me too.
To stay strong and upright, I do deadlifts. Like squats, they are highly unpleasant but highly beneficial for leg strength and back strength. If we spend 15 hours per day sitting, we must do what little we can to remain vital and to delay physical decay.
Physical and mental decay begins, according to the experts, in our late 30s.