themail@newyorker.com To the editor: That treadmill desk (May 20, "The Walking Alive", Susan Orleans) sounds lovely. I wish I could use one! Unfortunately, at this point in the progression of my neurological condition, sitting is a way of life:  My home features seating very few feet. On bad days I use my rollator (wheeled walker with seat) to get from room to room.  I rejoice in the hours I spend sitting at my computer, working or socializing without fear of falling and breaking another bone (as I did last summer) or of simply tiring myself to the point of cognitive/emotional malfunction (as I do nearly every day). I do not rejoice in the thought that one day my seating kluges will no longer be sufficient, and I will be confined to a chair for the rest of my life. The current fashion of demonizing sitting is painful and frustrating to those of us who have no other option.  Instead of scolding the seated, how about suggesting alternative exercises?  No, not swimming (a common suggestion) - how would I get to a pool without help?  How would I shower off the chlorine?  How would I get home?  -- I'm talking about isometric exercises, seated or reclining exercises... things we seated folks can do by ourselves, as simply and easily as the "walking alive" can walk at their desks.