I am training for mass, doing 6-10 reps.
I used to try 30sec - 1min... couldn't do it.
Especially when trying to do an increasing
pyramid with more weight on each new set.
(I don't try that anymore, even when doing sets.)
I either wait 1.5 - 2 minutes,
or I wait about 30 seconds and exercise a
different bodypart, alternating between 2
or 3 bodyparts. I do all my "sets" with
different exercises now (no 2 sets using
the same movement), so why not alternate?
It saves a lot of time and I can lift just as
much or more.