If you've been mixing things up with workouts #1, #2 and #3 you are going to love (and probably at times, hate) workout #4.
All of these moves will be familiar to you, which means you can really give 110%. As Irene would say, "Yay"!
The big difference here is that you're only spending five minutes at a time on the eliptical (or the treadmill or doing whatever cardio you choose). If you need ideas for cardio to do at home without any equipment, drop me a line at Erin.Kiernan@whotv.com and I'll give you some suggestions. Try doing the 20-40 format ... go as hard and as fast as you possibly can for 20 seconds, then go at a normal pace for 40 seconds. Do five cycles - then move on to a resistance round.