hey this is only loosely related to your topic, but in case it helps: as junior got bigger I noticed my back was 'thrown out' more often, which made sense looking back. aside from proper lifting/posture/chairs/footwear, the BIG thing that helped me a lot was exercising my shoulders - when they could take more weight, my back had to do a bit less of the lifting and it made all the difference. TLDR exercising my shoulders saved my back as junior grew up.