In the late 70s /early 80s it wasn't uncommon to train 4 hours a day and consume 500 grams of protein a day (yes, I did follow this routine when I was 17...hey, I lived in rural Germany and there was no internet, so please forgive me). Unsatisfied with the gains of the average non-steroid assisted trainee, he became convinced that the majority of people were over trained and drastically shortened his and his clients' workouts. In conjunction with Arthur Jones, he created his system of High Intensity Training or HIT. Basically, the trainee trained infrequently, 3-4 times every 2 weeks and did only one set beyond failure. He also added drop sets, negatives, partials etc.
There are many variations of heavy duty training. Dorian Yates, who is said to have been a heavy duty trainee, used in fact a much higher volume than Mike Mentzer ever prescribed.
Mike Mentzer became the somewhat anti-Arnold, anti-volume guy and spent 20 years of his life educating people about his style of training. He wrote several books on it (I highly recommend "Heavy Duty"), made training videos etc. In fact, he died in the midst of a DVD shoot in 2001 due to heart failure.
While this philosophy looks great in theory, there are several problems with it. First off, it is impossible to always train with maximum intensity. Mike is said to have used amphetamines to keep his training intensity high. The problem with that approach is that it will overload the CNS and lead to burn out. Remember, muscles recover quicker than the nervous system.
Secondly, the average person does not have sufficient neuro-muscular efficiency to reach all muscle fibers in one set. In fact, we only use about 10% of all available fibers per set. Hence, 2 or more sets are needed, the science is pretty clear about it. Thirdly, constantly training at maximum intensity makes you very injury prone; just ask Dorian Yates.
Does this mean that Mentzer was wrong? Not at all. He was the the first to point out that the majority of athletes do not sufficiently recover, restricted training to 60 minutes and he gave us negative reps.
The slow, controlled negative is probably Mike's greatest gift to us, as we now learn that the sarcomere damage it causes is in large part responsible for the strength gain.
A shortened full-body heavy duty routine is also an excellent way to stay in shape when traveling or if work demands the most of your life and you can only dedicate 60 min/week to your training.
Love a dose of strength history? Check out the other great bodybuilders in this series :