The ultimate guide to HIIT and its amazing results for improving cardio and body composition. HIIT (High Intensity Interval Training) is the No. 1 fitness trend and fast becoming the mainstream method for improving cardiovascular performance and radically changing body composition. This book aims to consolidate and demystify the science whilst also highlighting some of the lesser well known benefits of HIIT including improved levels of HGH (human growth hormone - which slows down the ageing process) and the generation of chemicals that have a positive effect on mood and wellbeing (not endorphins - something far more powerful). HIIT is in essence just a formula: (Exertion + Recovery) x Sets = Results. But it’s the versatility of the method that makes it interesting, you can HIIT indoors, outdoors, in water, in the gym with or without equipment, on a bike or on a rower. The growth in the popularity of HIIT is highlighted by the many fitness and exercise brands associated with it, including Tabata, Insanity, Spinning, CrossFit, P90X and Sprint 8, and this authoritative book introduces and explains them all. Written by globally recognised fitness authority, Steve Barrett and featuring more than 50 HIIT exercises and workouts, this is the ultimate handbook on HIIT for both fitness enthusiasts and fitness professionals.