Here's a quick movement exercise that may save your back from injury. The goal is teaching your body to move with a "neutral" spine (ie. avoiding rounding or haunching of the back under load). Simply place a cavaletti pole along your back, lightly holding it in place. You should have 3 points of contact: tailbone, mid-thoracic spine, and the back of your head. With the pole in place, practice bending and squatting while maintaining those points of contact. When you maintain this neutral spine you are able to produce more strength with less back strain. Give it a try and let me know how it goes.