I spent a few days in a rinzai zen buddhist monastery in upstate New York about 3 weeks ago. I was also initially skeptical, and in a lot of pain. Doing the retreat with other newbies, and talking about the experience with the monks during the informal meetings really helped. I still feel the effects of it - my crazy schedules at work and tight deadlines just don't seem to bother me anymore. It's wearing off a bit now, but I still feel much more focused, peaceful and "together". I highly recommend it. - I only went for 3 days though, perhaps I'll consider a 7-day retreat someday.