So what does “lifting like an infant” do to protect your back? Well, have you every tossed a ball to a 2-year-old and watch them pick the ball up? They walk up to the ball really close and perfectly squat down to pick up the ball up, keeping it close to the body as they stand. Nobody taught them this is the right way to do it, they just naturally do it!
We actually “un-learn” how to properly lift by getting lazy and this comes from our improved balance as we get older. If you roll the same ball to a bunch of 6 year olds, almost every one of them would invariably bend at the waist to pick up the ball and put more strain on their back. We learn that we can do it this way and create the bad habit at an early age.