I am not sure what 'isjias' is in English either! Obviously without assessing you / knowing the full diagnosis it is difficult to suggest what your best course of action is.

I have treated a lot of young fit males that have developed prolapses for various reasons and it is difficult know which way any of them will go. If caught and treated quickly enough some recover well and continue strenuous exercises all be it with the knowledge they must be aware of their back, others have resulted in surgery however.

If you imagine the middle of the disc a bit like tooth paste that has squeezed its way out through a crack to press on a nerve, or like a cake with jam in the middle, if you squash one side the jam moves to the other. Anything that you are doing day / day that increases the pressure on that disc, squeezing the paste / jam more will increase the pressure on the nerve and thus the pain.

Obviously having seen various specialist they have probably given you advice on how to manage your back....a good book that you may find useful is 'Treat your own back' by Robin McKenzie. Seeing a McKenzie trained physiotherapist may be useful.

You need to look at all the activities you do day to day, the cumulative effect that these may have on your disc. Often people tend to naturally adopt a postion that eases their symptoms at the time that are actually aggrevating their problem.

I would always suggest surgery as a last option, especially if there are things that you can do / positions that you can use that improve the symptoms and that the compression is not causing weakness or other symptoms that may indicate things are deteriorating.

Good luck