I've heard lots of conflicting things about whether or not cardio & weights should be done in the same day. When I have more time, I'll see if I can dig anything good up. I'm not a trainer, I'm an enthusiast, but here's something I came accross that may address some of what's being dicussed:

Let's hope my link works! It's a good article. The section that is pertinent is Aerobic Training, and how HIIT is more effective, read it all if you have time.

http://www.abcbodybuilding.com/foru...o=&fpart=1&vc=1