I include stretching into every workout - after the workout itself. Since I'm doing an upper-body (Upper Back, Chest, Shoulders) lower-body (Legs, Lower Back, Belly) split I got to a question, which I think can be answered pretty good on here:
Is it necessary to stretch my lower body after an upper-body workout?
I train both upper and lower body twice a week, stretching only the upper body on an upper-body day would cut like 10 minutes out, what would be quite nice.