 His first breakthrough became known as the 'Ideal (Principled) Routine', which was a fantastic step in minimal training.Outlined in "High-Intensity Training the Mike Mentzer Way", fewer than five working sets were performed each session, and rest was emphasized, calling for 4–7 days of recovery before the next workout.According to Mentzer, biologists and physiologists since the nineteenth century have known that hypertrophy is directly related to intensity, not duration, of effort (Mentzer 2003;39).