I've been doing HIIT for the past couple of months now. It's worked wonders.
I used to need a gurney when I left my judo club, but now I'm able to exit under my own power.
@TS: Regular (aerobic) jogging just doesn't cut it for combat sports, which are all a varying mix of aerobic and anaerobic types of exercise.
High intensity interval training is the way to go. Start with a light jog to get your muscles warmed up then sprint balls out for 20 seconds, jog for ten, sprint balls out for another 20 seconds, jog for ten, repeating a minimum of 8x.
Regular aerobic stuff works great for me. It has a long history with combat sports too. "You need to put in your roadwork" is something you hear all the time.
Interval training is beneficial too, but it's not going to substitute for basic aerobic training. Most people don't need to do much extra though because the actual rolling part is basic aerobic training once you get over the newbie hump. You just basically get out there and work at your pace for 45 minutes or so, taking a couple breaks in between, and doing little bursts occasionally where you need to.
It's actually the interval training that is not so much like rolling. That's why it's beneficial to do it outside of BJJ though because you won't get that from just doing BJJ. Nobody rolls balls out twice as much time as they roll at a more relaxed pace. If you are really going balls out, you might sustain that for 8x in your example, i.e. 240 seconds, i.e. 6 minutes. Then what about the rest of class?
Not everything you train needs to be exactly like what you do in BJJ. Nobody really bench presses people, but it can help to the bench press in a weight routine to make you stronger. You're never going to do a set of 5 heavy bench press movements in BJJ, so if you want to train that attribute, you need to do so off the mat.
If you can run six minute miles like the TS, you can roll through a class just fine. You just need to learn to relax while you are rolling. That's just a skill issue that takes some time. It's not a disease or grappling cardio being totally different. It's just being shitty at grappling, moving very inefficiently, spiking your heart rate trying to keep from losing, and gassing out accordingly.