[jome]

Obviously not ok - as others have already mentioned.

One thing I'd like to add is packing blackouts, which happen at the START of apnea. Not dangerous on the couch, but could be fatal in traffic. The upright position makes it especially risky. And while I say packing BO, it is entirely possible to get one with just a quick, full inhale if you're for example poorly hydrated and sitting upright.

Another thing - I don't know if this has been documented or researched, but after apnea I usually get a little "slow" feeling. It's like all my reflexes are reactions are slow, kind of like after a few drinks. I try to avoid driving a car for at least on hour after hard training for this reason. And obviously I do not train during traffic.

And as Benny pointed out - it makes no sense in training point of view either, no real training benefit so I think this is a no-brainer if you consider benefit vs. cost (risk) - the ratio is pretty poor.