I have a double hernia in the lowest part of my back. It used to hurt a lot, but I hardly have trouble with it now. When I feel it coming up again I do the excersises as told underneath. They are put down in excersise order Oh, and the groundexcersises i always do after training when done with the abs. But first some groundrules in dealing with your back:

1) make sure, that when you start training again, that you are training with the right technique. Make sure someone keeps an eye on that for a few months. To make sure you don't fall back in bad habits.
2) in the beginning, when the hurt is just gone for a little while, do stretch!!! The hurting spot is stil weak, so help it
3) do ab training. Good, strong abs support your back.
4) make sure you do enough cooling down. Not only for your back but for your whole body. It helps tremendiously in recovery from training. And prevents muscle-ache al together!
5) you indicate your problem is in the lower back. In that case it is usually not wise to do excersises that focusses on hollowing your back. It usually makes it worse. Only do bulging excersises.

Here are some simple but effective excersises (most of them we all do at the gym, so you won't look foolish doing them :
Remember, with excersises like these, to do them fully controllable, so no rushing!

lol, i've added some poor paint to hopefully make the excersises understandable

figure 1: twisting your pelvis
stand straight, with your feet a bit apart, slightly outside your body. Put your hands on both sides of your pelvis, thumbs pointing forwards.
Now without taking weight of your legs, kinda 'push' your pelvis to the left and back, and then to the right and back.
Repeat this about 10 times for both sides.

figure 2: stretching the side of your back
Stand the same as with twisting your pelvis, but now just let your arms hang.
Now turn your head to the left and bring your left hand to your left knee (still on the side of your body): lower your left shoulder as much as you can, following by bending your side.
Repeat this about 3 times for both sides.

figure 3: twisting stretch
stand the same as streching the side of your back.
THis excersise should be done slowely!!! now you have to do two things at the same time: you go slowely, inch by inch, go to your knee with both hands, while meanwhile your back turns and bends along. hold your position for a few seconds (it is ok if you feel a little strain (a slight comfortable strain so to speak) in your legs and / or back, but it may not hurt), and slowely go back to the starting postion. Wait one sec, and then to the other side. Repeat this about 5 times for both sides.

figure 4: bending over
stand in base position, both legs a little outside your body. If your not lithe stand wider. Now slowely bend forward. It is NOT nessesary to reach the ground!!! When your at your lowest without costing effort, try to focus on your back, and focus on letting the muscles there relax. You will notice you suddenly drop an few centimeters more! Hold this positioin a few seconds and slowely go back up. Do this about 2 times.

[img width=700 height=437]http://xs206.xs.to/xs206/06366/backexcersisesstanding.png[/img]

Ground excersises:
figure 1: pushing your pelvis
lay down on the ground. now push down your pelvis, so the lower part of your back comes flat on the floor. your knees may come up from the groud a little.
Repeat this about 5 times for both sides.

figure 2: bending your knees
lay in base position. Now bring one knee to your chest, hold it with both your hands, pull it a bit more to your chest, just enough so you slightly feel your back (again just at most a comfortable strain). Hold it for a few seconds and then slowely let it go. Then do the other knee.
Repeat this about 5 times for both sides.

figure 3: pushing your pelvis
lay down in base position. now WITHOUT moving your uppertorso/shoulders/arms push down one side of your pelvis, by lenghtening your leg. Push as far as possible. Then go back in base position and do the other side. Repeat this about 5 times for both sides.

figure 4: twisting your pelvis
lay down in base position. now at the same time do these 3 things:
- turn your head to the left
- pull in your knees and turn them to the right
- bring both arms to the left

When in position: Your knee closest to the ground, must touch the ground! The other knee must touch the 'groundknee' And just relax your arms. Repeat this for about 2 times for every side.

[img width=700 height=437]http://xs206.xs.to/xs206/06366/ligoefeningen.png[/img]

hope to have helped you!