Thanks for the replies.

I am on a very low dose of verapamil, but haven't had any issues on my bike. I do great, actually and put in 30 miles today. Didn't feel bad at all.

The TMJ/parafunction stuff has not been evaluated. Who would do a test and how? Would I have to go to a sleep lab? If so, I can't imagine I would be a good candidate. Can't picture myself sleeping there.