I can't speak to the personal trainer exam. But having taken (and passed) the ACE GFI exam last November, my experience is that some amount of study *is* needed. I had a background in representing disability claimants - which gave me some basic anatomy and physiology - plus 15+ years of taking aerobics classes and strength training on my own. So I probably knew about half of the material going into it. The other half, on the other hand, was really new and unfamiliar to me, and I had to apply myself to learn it.

I had about four or five months between the time I got the study materials and when I took the test. I did *not* study seriously for that whole time. But it probably would've been a month of real cramming.

YMMV, especially since it's not the same exam. But from the descriptions other people have posted, it sounds like it *is* the same exam!