Great cardio circuit with or without the treadmill running portion! You could also put these in between other body weight exercises to keep your heart rate up during HIIT (not that you necessarily need more cardio for that!
Shape Up: How to Do a 1-Hour Workout in 30 Minutes
Minka Kelly's treadmill workout: 1 minute at 1 minute at 1 minute at 1 minute at 1 minute at 1 minute at 1 minute at 2 minutes at Repeat five times. lost like in one week, running this every two days. It really works! Great way to loose weight fast!
The Best Belly-Fat-Fighting Interval Workout For Beginners