I did this workout last night and loved it. It's pretty basic: 5 minute warm-up at a light pace followed by 12 one-minute on/one minute off high-to-low intensity repetitions, and finishing off with a light 5 minute cool-down.
I like to incorporate pretty high-speed segments into my HIIT (greater than 8.0 MPH) to really get my heart pumping. As always, the workout can be altered to suit your fitness level. If you are a beginner to HIIT, try decreasing the high intensity speed to between 6.0 - 7.0 MPH and work up to higher speed intervals.
A workout like this will have your metabolism revved up for the day and will continue to burn fat for up to 3 hours after you finish!
3.6 miles in 35 minutes