Recently I've decided that I no longer wanted to dead lift the kind of weight I was used to putting on the bar. I used to start off my back workouts by dead lifting 135 as a warm up and then building up by increments of 90lbs all the way up to 495 for 2 reps. I never really had any back problems, nor did I ever find myself really straining to pull the weight, but I felt as though eventually (because I am not training for a sport and don't really have to lift that heavy for anything but bragging rights among friends) something might go wrong. I decided to simply stick to doing sets of 225 until failure and working in back extensions as my rest. Would that be a viable way to maintain a decent level of strength?
Any advice is appreciated.
Currently: 5' 10" 181lbs
Bench Press: 5x5 @ 265 RAW
Dead Lifts: 3x8 @ 315 RAW
Depends on what you mean by "decent strength"? If you never ever lift heavy and only do really high reps with light weights you will lose some strength. Besides you may be just as likely to injure yourself with light weights and high reps since technique usually starts to suffer as fatigue sets in. As long as don't max out all the time and maintain good technique, your chances of injury are relatively low. If it were me, I wouldn't quit doing heavy DL's but would only pull heavy every other week or every third week. I only pull every other week and work up to a heavy single, but not an all-out max and my back feels as good as it ever has. I just don't typically try weights that will require a really grinding effort or would cause me to lost technique.
I agree with Sean S, repetition efforts with 225 are just as likely if not more likely to injure you than low-rep sets with 495. If you're worried about sustainability, maybe go up in smaller jumps than 90lbs when you deadlift, and don't max out every time, like Sean said. You can also mix up normal deadlifting with rack pulls and platform pulls to change the output of the exercise. Listen to your body and focus on technique and there's no reason why you should hurt yourself.