Mark Sisson the Author of the Primal Blueprint would say this is chronic cardio. Going out and keeping your heart rate elevated too high (75 % and above) for too long of a time he does not suggest. I find that when I work with shorter, but more intense sessions the weight comes off. One of my favorite workouts only takes about 20-25 minutes total.
I run to the park (or other green space) 4 minutes away. I set up five cones about 15-20 feet apart from one another. I start at the first cone sprint to the second and then back to the first. I then sprint the third cone and back to the first repeating in the same fashion for last two cones. I allow myself about the same amount of time it took me to complete the sprint to recover before repeating 4-6 more times. I time myself for each sprint and try to be as fast with all subsequent sprints as the first. the goal is to work almost to your max with your heart rate. You want to feel like you are at a nine on a scale of 1-10. 10 being I need to sit down because I am working too hard. Most of my sprints last 40-50 seconds. I then jog back home or do some strength training at the park.
I look forward to doing more sprint work again.