You can also superset different muscle groups. For example, if you are training arms, you can make your workout more efficient by performing a superset for biceps and triceps. This way you are giving the bicep time to rest and hitting the triceps. Your heart rate tends to elevate when you don't rest in between sets. I would not consider this a cardiovascular workout but it is a great way to burn extra calories. The harder you train, the more calories your body is going to burn. It wouldn't hurt any of us to put some extra intensity into our workout.