The origianal poster posed a very interesting question which was: How do we reconcile the two pursuits of Budo (Aikido) and yoga (physical fitness)? If you look at yoga (I presume you are referring to Hatha yoga?), we in the West place an undue emphasis on the physical aspects on this spiritual activity. I believe this is where you contracted your belief that it's a fear of death activity, whereas my understanding of Hatha yoga is that it links the physical to the spiritual, very similar to Aikido. So in this regard, there should be no distinction between the two pursuits. You also mentioned that you became interested in Zen Buddhism. The Buddha taught after practicing some very austere flesh-negating practices, that the body is in fact very important because it's the vessel in which the spirit resides. Therefore it's important to take care of it and to nurture it up to a point - that is, not to pamper it. To the extent that we are healthy and unimpaired by illness and chronic pain, we need our bodies to enable us to attain spiritual enlightenment. So, for me, there is no paradox, they are mutually supportive and our training should also be so.