I’ve been coaching long enough to spot it from across the room — the slow forward creep of shoulders, the chin jutting out like a turtle emerging from its shell, the upper back curving into a shape that would make my old track coach wince. I see it at the YMCA, at the coffee shop, even in the mirror some evenings after a long writing session. Poor posture isn’t just a vanity problem. It’s a mechanical problem, a breathing problem, a confidence problem, and if left unchecked, a pain problem. And the market knows it — which is exactly why…