I think short bersts of energy is good for us and can produce results. High Intensity Interval Training, I've done it in the past, but yesterday, I jogged on and off a step for one min, then walked around the room for 1 min. I did that routine for 15 min. I felt the burn, no one is going to tell me that doesn't do anything for me. I think if you get your heart rate up a little, your doing yourself a lot of good.