Check out this video with UFC fighter, and one particularly known for his cardio and strength, Sean Sherk:
This is the type of workout I often do (+ sprints). It's mostly full body, muscle endurance + cardio. Very little rest between sets. Designed mostly to be able to go full speed for 3 five minute rounds.. Note the lack of isolation exercises, which seem to actually decrease coordination. The ropes are intense. I usually do 60 seconds of each, type, in a row. I'd start with trying 30 seconds of each. Remember, no resting, an no letting up.
If you want to see more of the gas mask exercises, which are shown at the end, check out this video:
People underestimate the blacked out gas mask. I've done it. I'm a guy who does not panic easily under physical duress, and I've fought through plenty of chokes and having my mouth and nose completely blocked, and the only thing that I can compare the blacked out gas mask to is being trapped in a "coffin", which I've done as well. I think that that is worse (you have the additional duress of not being able to really use your arms or legs effectively), but you really have to stop yourself from panicking when you are wearing the blacked out gas mask, much less do intense cardio while wearing it. These guys are tough, tough, dudes. That's not muscle to show off. Matt Hughes is one of the strongest dudes. He is not super cut or anything like that, but the man is a bull, and rock solid.