Surgery on my husbands testicles

So I have a question to see if anyone else is or has gone through what me and my husband are about to go through. My husband has a "twisted" vain that is knotted up and blocking his testosterone. We have been trying for 13 years to get pregnant and according to the doctor this is why. Although we did manage to get pregnant I lost the baby at 12 weeks . My question is, after the surgery, the doctor said he will produce more testosterone and have more stamina etc...SO HERES MY QUESTION.....will my husband basically be going through puberty again? I mean is he going to start losing weight and gaining muscle and pimples and whatnot? I'm kinda scared but glad cause he needs this surgery it has caused him pain and his body is reacting like a 60 year olds when he's only 33! I believe the correct term is testicular torsion. He is being seen in October and then we love to surgery soon after that. I guess I just need support cause I have no clue what this will do to him. I'm freaking out just a bit, should I be worried!?