The Arc Trainer is a great little cardio machine. I love it because you can make it any kind of workout you want. Take advantage of the incline and resistance. Switch it up every few minutes. One awesome tip I can suggest from this machine is to always push in your heels. Pushing in your heels will really engage your glutes for a little extra booty work!!!
A swing lunge is a repetitive front to back lunge over and over before switching to the other leg. In other words, lunge front and the same leg that lunged front now lunges back, AKA reverse lunge....but do not switch legs! The same leg will lunge again, front back front back for a total of 20 reps and then you would switch to the other leg.