In my opinion i think its's just another tool in your toolbox and when used correctly can be very valuable not only for the purpose of fat burning but to better condition athletes in their respective sports which involve periods of high and low intensities like soccer, football, hockey etc....Great Video keep up the good work.
I will be 66 soon and hit the treadmill for 30-35 burning about 450 calories, after a 5minute warm up i have the incline at 15 and speed up to 4.0 which is a brisk/fast walk, my cardio is pretty good for my age
I like the way you point out in order to get the results seen in the "research " one would indeed have to perform the task at research intensity (puke level).
