There have been numerous studies involving interval training. Here is a list of abstracts from studies and articles which discuss interval training. Please refer to this list and check back for more additions in the future.
Brief, Intense Exercise Can Benefit the Heart, Study Shows
Can You Get Fit in Six Minutes A Week?
Effect of an acute period of resistance exercise on excess post-exercise oxygen consumption: implications for body mass management. Recent addition to list
Effect of High Intensity Interval Exercise on Lipid Oxidation During Postexercise Recovery
For Heart Health, Sprints Match Endurance Training