Stress — like everything really — is not simply a psychological problem. The body plays a big part in our experience, and, it turns out, our capacity to deal with it. From mindful.org:
A new study in the journal Biological Psychology suggests that people with better body awareness tend to feel less stressed. That’s no surprise, perhaps, if you’ve already been practicing mindfulness, but may seem odd otherwise. Stress leads to a physiological response, such as increased heart rate or sweating.
Participants who reported themselves less overwhelmed by a challenge also noticed their physical state sooner that others—with brain scans suggesting they were able to reign in anxiety before it escalated.
I’m not too familiar with zazen so I had no idea what the difference between zazen and meditation might be, but it turns out it’s pretty interesting:
In most meditative traditions, practitioners start a certain method of meditation (such as counting breaths, visualizing sacred images, concentrating the mind on a certain thought or sensation, etc.) after getting comfortable sitting in full-lotus position. In other words, it is kekka-fuza plus meditation. Kekka-fuza in such usage becomes a means for optimally conditioning the body and mind for mental exercises called “meditation,” but is not an objective in itself. The practice is structured dualistically, with a sitting body as a container and a meditating mind as the contents. And the emphasis is always on meditation as mental exercise. In such a dualistic structure, the body sits while the mind does something else.
For Dogen, on the other hand, the objective of zazen is just to sit in kekka-fuza correctly—there is absolutely nothing to add to it. It is kekka-fuza plus zero. Kodo Sawaki Roshi, the great Zen master of early 20lh century Japan, said, “Just sit zazen, and that’s the end of it.” In this understanding, zazen goes beyond mind/body dualism; both the body and the mind are simultaneously and completely used up just by the act of sitting in kekka-fuza. In the Samadhi King chapter of Shobogenzo, Dogen says, “Sit in kekka-fuza with body, sit in kekka-fuza with mind, sit in kekka-fuza of body-mind falling off.”
If you truly embrace the idea of mind-body unity, this approach probably won’t strike you as particularly outlandish. Rather than saying that zazen and meditation are not the same, I think it’s more accurate to say that they approach the same thing from different perspectives. Still, it’s always interesting to hear about those different perspectives.