I have been doing some reading on this "peak 8" training theory. Take a look. I am incorporating more into my workouts (with the help of a coach). Makes sense.....we will see. Matt is already seeing success in his TRX workouts which uses a similar format.

http://fitness.mercola.com/sites/fitness/archive/2010/06/26/10-minutes-of-exercise-yields-hourlong-effects.aspx

BTW.....subscribe to the mercola website. He is "tabloidy" to some extent but there are some great articles.