A different approach: Take up a wind instrument.
Yeah…and I thank you. But that is not going to happen. 
I’ve been continuing to do my walking jogs and now I add a sprint up the stairs at the university, about a two story climb, three times and then a walk around the campus and then again and then a walk and then again. Basically, breathing hard for an extended period of time, stretching out the rib cage.
So far so good. 
I’m surprised nobody’s mentioned this, but you should do some breathing exercises for singing (after all, singing is all about maximising your lung capacity and controlling air release, no?).
Google ‘breath control exercises’. You’ll find a wealth of exercises that you can do any time of the day, both typed out and on youtube, that really help you to learn how to breath properly and expand your capacity. Because they’re so subtle you can really do them anytime, just take ten minutes here and there to work on a few everyday 
It won’t get you fit and healthy in other ways… but if you’re already doing other things, it’s a good boost!
[quote=“tsukinodeynatsu”]I’m surprised nobody’s mentioned this, but you should do some breathing exercises for singing (after all, singing is all about maximising your lung capacity and controlling air release, no?).
Google ‘breath control exercises’. You’ll find a wealth of exercises that you can do any time of the day, both typed out and on youtube, that really help you to learn how to breath properly and expand your capacity. Because they’re so subtle you can really do them anytime, just take ten minutes here and there to work on a few everyday
It won’t get you fit and healthy in other ways… but if you’re already doing other things, it’s a good boost! [/quote]
Funny you mention singing as I was doing just that this AM on my walk!
I have good days and bad, usually, mornings. Woke up at 6Am today because every time I exhaled it felt like that damn 4th grader was sitting on my chest. 
Have a look at this:
This should help you a bit Other breath control exercises on youtube are quite good, I just particularly like this guy.
[quote=“kau826”]Hi jdsmith, do you seriously have ankylosing spondylitis? I’m sorry to reconfirm this 'cause I hardly can believe to meet someone with a problem that I know of.
I highly recommend you to check up the LAB first, although sometimes they are not so reliable 
. The doctor will arrange some tests to confirm the existence of inflammation, which renders the different ways of medical control. The doctor will also see your chest and evaluate whether your rib cage is completely or partially restricted. Then the strategy is tailored according to the clinical and laboratory findings. If the pain in the chest or back is not well controlled, you would dare not take deep breath and your rib cage will be restricted further, causing more pain and resulting a vicious cycle.
[/quote]
I would add to Dr. Kau’s note that ankylosing spondylitis can cause (strictly speaking can be associated with) interstitial lung disease. (I remember it because it’s the “A” of the “CASSET P” mnemonic for causes of upper-lung zone interstitial opacities on chest x-rays.) So, think about asking your doc about a chest x-ray, though a chest CT would be more sensitive to detect subtle early changes.
Cardiovascular exercise. Running and swimming, I try to do about 30 minutes a day.