How to help DS through this

[Wartsandfall]

DS15 competes at relatively high level for his sport. It's the only thing he does, is completely obsessed and hopes to do this professionally in some capacity.

Has had niggling injury for a while now and have now found out that he needs to completely stop all sport for 6-9 months to recover. DS doesn't yet know this.

He has injuries before and been out for 2 months. During this time, his behaviour and home and school decline massively. He needs to exercise for his mental health, and without it, everything falls apart. He's also in yr 11 now, so added stress.

how best can I support him? Feeling heartbroken for him and worried how he (and us tbh) will cope. Looking for alternatives that will give him the adrenaline and release he needs but struggling. Any ideas??

That's tricky. Intense exercise does seem to be very beneficial for mental health, I've seen it make a huge difference to several young people.
Is there anything that he could take up instead that would require hard training but not of the injured part? Swimming? Weight lifting?

Is it a particular mechanism that he needs to rest (eg specific joint or muscle) or all exertion (eg. Heart problems)

If it's a specific joint, maybe see if you could work with a personal trainer to do some fitness/conditioning sessions so he can still play at a decent level once he's fit again?

Could he do youth coaching or help at training sessions running drills etc to keep him in the sport world while he's "out"?

Are there complimentary sports that don't use the affected area, eg if he has a knee injury, could he try walking football instead of running, or wheelchair basketball instead of able basketball?

Any opportunity to get involved in coaching others/younger children or even children with additional needs - with “supervision” by adult coaches?

That's difficult, OP. But some of the suggestions above are good (it depends on the sport and the injury). If doing alternative training is a possibility, that would help. Some martial arts (and proper Tai Chi) are helpful for strength training and coordination etc, or swimming is good (although one of these might be the sport your DS does usually).

Also, your DS might not appreciate it, but there are a lot of elite sports people who have had time out for injury etc. Finding out how they managed could help him.

I hope he recovers and can get back to it.

Aw poor lad. I don't have any suggestions but hope he manages to find an alternative.