A Doctor I work with printed this article from the May 3rd issue of The New York Times for me. I think everyone who exersises, and those who are thinking about starting an exersise program may find it of interest. It's not a very scientific or technical article.
Basically, it states that researchers tested a few groups of people one group was sedentary and one already active, and found both groups showed a significant increase in endurance after just a few weeks of interval training. one to two times a week. For dieters, Interval training apparently showed an increased ability to burn fat as well. (Something I'm very interested in as well.
Now, there was no "control group" of people who didn't do the interval training. For some people this makes this an invalid study. I realize techincally speaking, it probably is invalid in that manner. A control group, however, in this instance would just continue doing whatever they had been doing for exersise before. With no change in exersise intensity or duration, I doubt the control group would see an increase in endurance or speed, so I'm not too worried about the lackof a control group.
I'm happy to discover more "evidence" that Interval training does work in a variety of ways. I plan to keep it as one day of my running…and I really hope it lives up to it's promises!!11