Eli5: why do babies sit with perfect posture when they learn to sit, but the older you get, the worse it gets?

Question

Babies sit straight up naturally. But the rest of us have to put effort in to having good posture, why?

In: 1304

Answer 1

More balanced function of muscles. Our posture gets worse because we get weak and tight by lounging in chairs and not utilizing muscles through their full range. Go to Eastern Asia and you’ll see plenty of adults sit with good posture effortlessly.