There's a lot of reasons for lower back pain and I don't think that what I'm about to share is the biggest reason but it no doubt is a big one just the same. At the moment, I'm just stunned that after all of those posters covering the walls at just about any work place where you might have to lift something off the floor on a regular basis, people still don't use their legs to lift a heavy object. Always with the back. I was working at a construction site recently and I almost never saw anyone lift anything with their legs, including my co-worker.
I wrote recently about how I got rid of what modest amount of back pain that I had by leg exercising and in closing I mentioned that strengthening the legs would help with back pain since if your legs were strong, you wouldn't have to lift with your back. Now I see there is another angle to that: The more you exercise your legs with squats and lunges, the more likely you are to pick something off the ground with your legs rather than your back. It isn't just that your legs are stronger, it's also that after so much leg work, it becomes second nature to bend at the knees to pick up a load, rather than at the back. It's muscle memory that will save your back in the end.
I never mentioned in my last post WHAT I was doing as far as routine or exercises, so here's a taste of what I was doing.
1. Warm up, 100-300 hindu squats (depends on how much time I have to work out)
2. Jowett Lunges, 10 reps each leg
3. sissy squats, 20-30 reps
4. DVR/DSR for the Leg (Such as a DVR Squat)
5. Isometric set for the legs (wall chairs)
I would repeat this set for 3 sets, usually changing the DVR/DSR and the Iso set each rep, working around my thighs and hitting the calves properly. I try to make sure that I hit every muscle in the legs somewhat evenly. I'll often change and do some different squats and/or lunges.