Not sure what you mean by throwing out the back. Disc/muscle problem or both? Doctors advised now-a-days to move around and be active rather than staying in bed or take it easy until the back returns to a somewhat normal state. If you open your back door and a mountain's there ready for hiking than that would be a perfect world for you. Hiking involves using your body weight +, one leg at a time, which can help self aline the spinal structure as well as affect any muscle imbalance that goes along with a out of line back. As you first move you might visit a medical professional to get some advice as to the cause of the lower back problem. If your disc is a problen than by all means see a doctor.Seeking advice from strangers on the internet is not always the best idea. Saying that, I might suggest seeing a chiropractor, acupuncturest, deep tissure massage, etc. A sports doctor, though helpful, is too much money for the average guy. My first choice would be acupuncture or deep tissue massage.
There are many exercise that can strengthen the back area and even help realine the spine and muscle imbalance. Work the abs just as strongly as the lower back, each will balance out the other. Might try GoodMornings (exercise bar only) sitting on a bench and touching the chest to the bench each rep. Do not round the back and keep the head somewhat up and shoulders back as you do the movements. Next do a set of standing GM'ing with the knees slightly bent, again with only the exercise bar. Try 20 to 30 easy reps with both these exercises for two sets each, at least three times a week. As the back becomes stronger and you feel more confident than add weight each progressive workout. The low back is a very powerful muscle groupe once you train in the correct way. Couple of guy's I know use 300+ for GM'ings in their regular workouts. Do a set of ab crunches between each set of GM'ings, remember the link between the abs & lower back. This is the foundation of strength and does insure good back function. IN the mornings do 30 reps or so of standing GM'ing for a full stretch with the hand held behind the back only.
Might also try one leg step-up's from a middle height bench or sturdy box. This can mimic hiking/climbing which seemed to have a favorable effect on you. The bench/box is in front of you and you step up onto it. A one legged squat is when the bench/box is along your side as you press up with your leg. Athletes include step-up quite a bit in their training. Always a good idea to train the legs, from time to time, one at a time to be sure they are developing and gettin a equal amount of work. With squating, sometimes one leg is favored over the other. Can include both versions in a regular workout if you wish, step-up/one legged squat. You don't have to baby your back after making progress, only take a little precaution as you exercise.
I had a major disc operation (L4-L5 mostly) after my last game of college football. Surgery is always a risk but in this case there was no option. At present the back is strong and healthy (I'm one of the guy's who does 300+ GM'ing for example) and I do still lift very heavy but there are day's when it will tighten up a bit. That's when I do a lot of extra stretching. I also do Yoga movements quite a bit for body flexability. Good Luck.