sleep apnea
my main 'practice arena' appears to be the bed i.e. I have the 'problem' of sleep apnea, it seems zzz. That is, for me it isn't a problem (at least not yet!), but it scares the crap out of my wife!
Maybe it's not so funny - a friend of hers died of a heartache (but he was 75 or so) after being diagnosed a couple of years before as a sleep apneaist

Apparently the strain on his heart over years and years of not sleeping properly (he was going into apnea between 15 and 20 times an hour, as observed in a sleep clinic, which meant he never got into the deep sleep that you are supposed to REALLY need!!!) did him in.
On the other hand, maybe that explains why I was always good at diving, even without practise?
I even went to the doctor about this, but he wasn't terribly helpful, suggesting a throat operation, that 'probably wouldn't help anyway' - I turned it down.
I don't suppose anyone else experiences this, do they?