As a good friend once told me, " A good back is a terrible thing to waste." That always makes me think of dead-lifts and the strain that can result from poor technique. Everyone is built differently, longer legs, shorter legs, long torsos, short ones. However there are some things that are vital to good dead-lift technique.
1. Initiate the movement with the hips/glutes. This assures the largest muscles in your body are being recruited first, and therefore saving that lower back for when you need it.
2. Keep your head up and look straight ahead. This will generally keep the top of the back flat and avoid rounding of the shoulders.
3. Initiate the movement with the bar under your shoulders, with the bar up against your shins. This will keep you from "reaching" and thus straining the lower back unnecessarily.
4. Pull the bar from the floor with power. Avoid "jerking" at the bottom of the movement. This will help keep everything in good alignment and sequence.
5. Return the bar to the floor in the reverse sequence. Just because you have executed the lift, don't forget how you got it there. You can get careless and rely on that lower back returning the bar to the floor just as easily as using sloppy for lifting it.