Muscles of Iron

High Voltage Bodybuilding and Heavy Lifting

Does Heavy Duty Training Work?

Remembering Mike Mentzer - Part 3

By Robert Drucker

Since the publication of the original Heavy Duty course in 1978, Mike Mentzer has established a huge fan base. To his loyal followers, Mentzer was like a god, a savior who shined bright light on the nature of productive exercise. To these folks, Heavy Duty is the final and ultimate word on muscle building.

But, there are also a great number of folks in the bodybuilding world who are less than enthusiastic about the Heavy Duty training protocol. Die-hard members of this clan argue that the basic premise behind Heavy Duty is undeniably wrong, and that commercial interests, not the revelation of truth, is the driving force behind Mentzer's books and courses. More generous members of this group merely claim that " the Heavy Duty training system may work in theory, but not in practice."

Somewhere between the loyal fans and the harsh critics, a remaining group of bodybuilders juggle the teachings of Mike Mentzer against the teachings of the traditionalists. Members of this group are somewhat bewildered by the vast number of opinions that seem to permeate the strength world in nearly every direction. But, to their credit, they are willing to consider arguments from both sides with an open mind.

Whether a devoted fan of Heavy Duty, a harsh critic, or an open-minded skeptic, members of all three groups have one thing in common - they have lots of questions about the Heavy Duty training system, and they want logical answers to these questions. Since I posted Part 1 and Part 2 of this series, reader feedback has been literally amazing, and I have been flooded with questions about Mike's version of high-intensity training. These questions have come from Mentzer supporters and critics alike. Some of these questions were posed for serious discussion and to attain a better understanding of key principles; others were thrown at me as a challenge to my way of thinking. In either case, readers want an answer to one question more than any other: Does Heavy Duty training work?

Well, this is not a simple "yes" or "no" question. For one, the Heavy Duty training system was refined many times by Mike Mentzer over his final years. Two, how well Heavy Duty, or any other method of training works, depends upon a lot of factors, not just on the inherent merit of the system. Three, how Heavy Duty is specifically applied in the gym can make all the difference in the world. An improper application can render this, or any other, training method ineffective. Finally, the argument that there are many bodybuilders out there who have "tried" Heavy Duty training and failed to make significant progress proves absolutely nothing. The same argument can be said about any other training method.

There are many reasons why a healthy bodybuilder may fail to make meaningful progress even though he or she is using a training program based on valid principles. Poor training habits and overtraining immediately come to mind. However, there are other potential causes of lack of progress, and they are often overlooked, even by most exercise "experts". These progress destroyers include job or marital difficulties, worry, depression, physical illness, general nervousness, poor eating habits, sleep deprivation, exposure to the elements (the sun's rays, high temperatures, toxic chemicals, etc.), mental strain, and worry. All of these destroyers have one thing in common: they cause stress.

Stress of any type always manifests itself with both a local component and a general component. The local component is specific in nature, and it applies only to the portion of the body directly "hit" by the stressor. The general component affects the body as a whole, and its form is always the same regardless of cause.

Consider what happens, for example, when you are overexposed to sunlight on a hot July day. Not only does your skin redden and burn (local effects), you also become exhausted, worn-out, and lethargic, and you may even develop a really bad and long-lasting headache (general effects). I point this out to demonstrate a crucially important observation: any form of stress will drain the body of energy to some extent. If the stress is intense enough and/or significantly sustained, energy drain can be severe enough to make training progress next to impossible. In this sense, it is possible to "overtrain" without training at all, if your stress level reaches a critical point.

I emphasize that there is a general response to any form of stress because many bodybuilders do not realize that lack of training progress is often the result of drained energy reserves, whether caused by overtraining or by overexposure to some other type of stressor. I know this to be true not only from theoretical study of physiologic science, but also from personal experience. What this means is that it is likely that a valid bodybuilding system will fail if either the right application is not applied, or if everyday stresses are significantly high.

I should also point out that destructive psychological factors (such as negative thinking) can also have an adverse effect. If a lifter expects Heavy Duty, or any other training method, to fail, then it is highly unlikely that he or she will put forth the effort necessary to achieve maximum results. We all have heard about the power of positive thinking. Well, negative thinking can be equally powerful, but in the opposite direction. I have seen many bodybuilders fail to make progress simply because they expected to fail.

Let's now look at what I mean by "right application". Let me begin by stating that Heavy Duty is based on sound and fundamental principles, namely that productive bodybuilding exercise must be intense (to trigger the growth process), brief (if you train hard, you can't train long), and infrequent (enough time must be allowed between training sessions to allow the muscle-growth process to take place). No logical bodybuilder would argue that any of these three basic tenets are incorrect. Thus, we must now conclude that the Heavy Duty system of training is sound, valid, and potentially productive. I say "potentially" productive because how well Heavy Duty can work for you depends on how you specifically apply the basic principles and training strategies that comprise the system. And, as previously mentioned, other factors (such as stress level, degree of motivation, etc.) play a big role too.

An example will help make this point more clear. I first experimented with the Heavy Duty training protocol in early 1979. At this time, I was just 15 years old, and I was training for the Teenage Mr. Kentucky contest. For a short while I made good progress by using the exact routine that Mike Mentzer recommended in his first mail-order course. But, over time, my gains slowed down and eventually came to a halt. After three weeks of little or no progress, it became apparent that no further work on Mentzer's suggested routine was going to stimulate any further gains in size or strength. I became somewhat distraught by the ineffectiveness of the routine (the specific application), so I abandoned it and moved back to a more traditional style of training. I also falsely concluded that the Heavy Duty training system had no merit.

In 1993, 14 years after my first experiment with Heavy Duty, Mike Mentzer released a revision of his Heavy Duty course. Upon seeing an ad for his new book in Muscle Builder magazine, I immediately ordered a copy. I was very eager to read Mike's latest work, if for no other reason than I really liked his writing. To this day, I still greatly enjoy reading articles that were penned by Mike, and I consider him to be one of the most thought-provoking and prolific writers in bodybuilding history.

When my copy of the revised Heavy Duty course arrived in the mail, I started reading it with immense anticipation immediately. I was quite surprised to learn that Mike had made significant changes to his suggested training routine (specific application). He explained that he had refined his system over a period of many years based on new information that he had acquired through his own training experiments, and by observing how hundreds of his personal training clients had responded to his instruction.

Mentzer came to realize from his vast research that although Heavy Duty was a viable and potentially powerful training system, a number of his clients failed to make significant progress because his suggested routine was too demanding for them. During a series of experiments, Mike had his struggling clients reduce their training sets, increase the number of rest days between workouts, and perform forced reps more sparingly. What he found is that majority of his hardest gainers started making significant and lasting progress. And, in many cases, the progress was extraordinary. Mike's conclusion was that he had greatly underestimated the energy-draining nature of Heavy Duty, and that his original suggested routine (the one I had used at age 15) was too demanding for the average drug-free trainee, and perhaps even for advanced lifters.

After reading about how Mike had refined his training system, I decided to give Heavy Duty another chance in early 1997. This time, however, I reduced my training frequency to just twice a week, and I trained each body part only once per week. I also limited the number of exercises I did to no more than two per body part, and I did no more than two work sets per exercise. To my pleasant surprise, this type of training produced some of the best long-term gains I had seen in years. And, the reduced training frequency allowed my then aching joints to fully recover and heal. This was proof positive that Mike's Heavy Duty method of training is valid and effective, at least for me.

However, I must believe that if Mike's system works for me, it potentially can work even better for the majority of lifters. Why? Because I do not particularly have favorable genetics for gaining muscle size and strength. I am light boned and a hard gainer by nature. Most bodybuilders simply grow faster than I do, all things (other than genetics) equal.

If you are failing to make meaningful progress while training Heavy-Duty style, this does not necessarily mean that Mentzer's style of training cannot work for you. As mentioned previously, there are many factors that can mitigate against a successful application of Heavy Duty (or any other system of training). I list eight such potential factors below that I commonly see. The trainee should review these possibilities before throwing the towel at Heavy Duty. In many cases, a tweak here, or a tweak there can turn a Mentzer type of training program into a goldmine of muscle.

Possible Mitigating Factors of Heavy Duty Success

  1. Overtraining
  2. Excessive stress
  3. Poor eating habits
  4. Lack of training intensity
  5. Poor exercise form
  6. Not seeking to use heavier training poundages
  7. Unrealistic training goals
  8. Failure to make necessary adjustments


When it comes to overtraining, bodybuilders often suffer from self denial. Therefore, take a hard look at this possibility and be as objective in your assessment as possible. If you suspect that you may be overtrained, take one or two weeks off from training, or longer if the problem is severe. A break from the gym will be necessary to replenish your energy reserves and mobilize your inner forces. Upon resumption of training, reduce your workout sets and/or training frequency. Also, be careful not to overdo the forced reps. Too many forced reps can wreak havoc on your nervous system.

As mentioned previously, if you have too much stress in your life, muscle growth will be next to impossible to attain. A successful bodybuilder must find a way to control stress and achieve a state of tranquility. If you continue to suffer from excessive stress, you may want to consider seeking the advice of a professional counselor.

If you are skipping meals and eating like a Canary bird, you can't expect to pile on pounds of muscle mass. Mentzer stressed the importance of establishing a well balanced diet with daily portions of cereals and grains, fruits and vegetables, high-protein foods (fish, meat, eggs, poultry), and milk products. Mike was not a big fan of food supplements, however.

If your workouts lack intensity, then you will probably fail to set the muscle growth mechanism into motion. Remember, you must complete that last possible rep in order to fully stimulate muscular growth. In short, you must perform gut-busting work if you want to reap the most from your Heavy Duty training.

As described in Part 2 of this series, Mike Mentzer recommended training with slow and deliberate lifts, both when raising a weight and when lowering it. Remember, the goal is to achieve a high degree of muscular contraction, not to merely "lift" a weight in any way that you can. Proper exercise form is essential to achieve full muscular contractions and make optimal progress.

Lack of motivation will drive any training program into the ground quickly. If you are having trouble staying motivated, then you must find the reason why and eliminate the root problem. The successful application of Heavy Duty requires extreme motivation and drive. The only way to stay supercharged psychologically is to stay healthy, avoid overtraining, avoid excessive stress, minimize contact with negative-minded people, and keep your mind flooded with images of heroism and accomplishment in any way that works for you.

Many bodybuilders fail to make meaningful progress simply because they don't push themselves hard enough. If you don't aim to handle heavier iron (in good form, of course) or to perform a greater number of repetitions every single workout, then you can't expect to make optimal progress. Mentzer stressed that in order to get bigger, you must first get stronger.

A fair assessment of Heavy Duty, or any other training method, should be based on realistic expectations. All too often, an exercise enthusiast sets "out-of-sight" goals, and then he abandons a sensible and logical method of training because it doesn't produce the unrealistic results expected. He then moves on to another method of training, and it too "fails". This trend continues until the bodybuilder becomes so frustrated that he quits training altogether.

Mentzer never claimed that he discovered a single, one-size-fits-all workout. In fact, in his book, Heavy Duty II: Mind and Body, Mike acknowledged that his suggested start-up routine may not work for everybody. As an alternative, he suggested an abbreviated workout program, one consisting of just basic compound movements. The important point here is that there are unlimited ways (specific applications) to train in Heavy Duty fashion, and some of these ways may work better for you than others. This said, I should point out that, in most cases, doing more exercise is rarely the solution to lack of progress. More often than not, Mentzer found that most of his training clients had to reduce their training volume and/or train less frequently to break out of a training rut. This is explained further in Part 2 of this series.


The Heavy Duty training system is built on sound and fundamental training principles. With a proper application, and if potential mitigating factors are controlled, Mike Mentzer's system of training has proven to work for thousands of bodybuilders. It is one of my preferred methods of training, for I have made good gains with it with a minimum amount of time investment.

Is Heavy Duty more effective than all other known methods of bodybuilding training? I do not have enough data to say for sure. But, I can say that I have personally seen Heavy Duty work wonders, not only for myself, but for some of my former training partners and associates. Today, my workouts are based on a combination of Heavy Duty methods and Dinosaur training, and I am still making progress at age 47.

What Do You Think?

I don't claim to have the last word on this subject, and I don't expect everybody to agree with each of my conclusions. Your comments about the Heavy Duty training system are welcome, whether you agree with me or not. Please let us know what you think.


  1. Mentzer, Mike, Heavy Duty, Published by Mike Mentzer, 1993
  2. Mentzer, Mike, Heavy Duty II: Mind and Body, Published by Mike Mentzer, 1996
  3. Little, John and Sharkey, Joanne, The Wisdom of Mike Mentzer, McGraw Hill, 2006