I completely agree with the comment that using empty EMT fastened between joists to hang fixtures is a good approach, but just wanted to mention an experience I had some years ago. Contractor did just that, and it was illustrated in the installation instructions for a can light - in fact, the manufacturer punched tabs in the can support plate, bent up to accept EMT. After the fixtures were installed, an Electrical Inspector said all the EMT had to be removed because it was not UL listed as a support product. Personally, I think the inspector had too much coffee that morning, but as we all know, the AHJ has the last word.