Hey Boodgie!!!!
HAHAHAHA....funny to find you here!
Seriously, in response to your question...
my teacher espouses 20 minutes twice a day, before breakfast and before dinner...
The scientific research I have studied on the effects of meditation support this also.
Of course, meditation is a very personal and individual experience...so this is just a beginning guideline. When I first started, I couldn't sit still very long at all before I just wanted to run out of my skin!
Oh, one more thing...If you go on retreat, don't bring your best fun guy yoga friend along if you want to concentrate at all!!!!
Lovin' you! See ya Sunday!
Pixie