Foundation UK and the Insulin Dependent Diabetes Trust. He is a member of the PCOS alliance, European College of Sports Science and the American Physiological Society. Most training styles dealing with Health and Fitness has been both debunked and proven time and time again. It's all about circumstances and the individual. I can say first-hand that using a HIIT cardio session has given the majority of my clients the push they've needed to break through plateaus and get their results BUT relying solely on it for results is a bad idea. You can't rely on just one thing to fix everything. Health and Fitness is a multifaceted discipline. I have been trying the 8/12 HIIT system for a month or so now and have seen a good general improvement in my fitness as measured by blood pressure and resting HR, however due to some dietary changes I have also lost around 10kgs (edit: not over a month or so I should add) and hence any improvement could also been down to this.......The research for the 8/12 system looked good and it certainly gets me sweating about half way though the session and I can keep my HR up around 85% of max. (lifesprints.com)