6 Heavy Duty Training Tactics

Lessons From Mike Mentzer

The muscles. The mustache. The madness. Here’s what you can still learn from Mike Mentzer’s Heavy Duty training.

A Quick Glance Into Bodybuilding History

Mike Mentzer was an incredibly influential bodybuilder in the 1970s. He was a student of Arthur Jones and an advocate of Jones’s HIT (High Intensity Training) method.

After retiring from bodybuilding, he took HIT even further, advocating very low volume, low rep, heavy training with multiple days of rest between each workout. Each brutal session consisted of a small number of exercises performed for 6-9 reps to failure and often beyond. Forced reps, super slow negatives, and rest-pauses were common.

This became known as Heavy Duty training and, like Mike Mentzer himself, it was controversial and highly debated, though six-time Mr. Olympia Dorian Yates used a variation of this type of training.

Many say that Mentzer took the idea of HIT too far, but his ideas are still thought provoking. Here’s what you can learn from them.

1. Use High-Intensity Muscular Contractions to Grow

Mentzer believed in training all-out with incredibly low volume, then recovering – sometimes taking as long as ten days before training a muscle again.

Mentzer’s definition of intensity doesn’t refer to the percentage of one-rep max, but rather the difficulty of an exercise and how close you’re working to complete muscular failure.

The volume seems to be too low to succeed, but research by Carpinelli and Otto (1998) and Smith and Bruce-Low (2004), concluded that one set per exercise produces good results. In their papers, they found that single sets produced optimal results in 33 studies out of the 35 they reviewed.

Mentzer focused on gradually increasing training intensity, rather than training to failure right off the bat. Once a lifter is capable of creating high amounts of tension in his muscles, the key to building more size isn’t to train longer and with more volume; it’s to use increasingly intense methods and make training more difficult.

Mentzer used rest-pauses, drop sets, and pre-fatigue methods to take exercises to complete and utter muscular failure. He believed that tapping into this level of intensity was the key to unlocking further strength and size gains.

Further, he was an avid proponent of integrating tempos into his training to focus purely on creating the hardest muscular contraction you can, rather than leveraging momentum to throw weight around.

Though you may not agree with Mentzer’s ultra-low frequency, low-volume approach, you can still benefit from his wisdom. Control each rep to maximize intramuscular tension. Push the intensity on every set to the point of technical failure and, occasionally, muscular failure. Chances are, you’ll benefit from doing less (but better) in your workouts.

2. Do Minimum Effective Dose Training. Get Maximal Recovery

Mentzer believed the majority of lifters overtrained and under-recovered, limiting muscle growth. When coupled with low overall training volume and comparatively infrequent workouts, he preached that any exercise carried beyond the “minimum effective dose” is wasteful and counterproductive.

He focused on one or two total work sets per exercise with two workouts per week separated by at least 48 hours. A classic three-workout rotation could be:

  • Workout One: Chest, Shoulders, Triceps
  • Workout Two: Back, Biceps
  • Workout Three: Legs, Abs

Here’s a sample chest, shoulder, and triceps workout:

Do one to two warm-up sets, then one set to complete muscular failure for each exercise:

Exercise Sets/Reps Tempo Rest
A Dumbbell Incline Flye 1x6-9 4240 1 min.
B Barbell Incline Bench Press 1x6-9 4240 1 min.
C Lateral Raise 1x6-9 4240 1 min.
D Lying Rear Lateral Raise 1x6-9 4240 1 min.
E1 Cable Triceps Pushdown 1x6-9 4240 1 min.
E2 Parallel Bar Dip 1x6-9 4220 1 min.

Here’s what the dips would look like using that tempo:

Due to Mentzer’s all-out training methodologies, his philosophy epitomized the idea of “get in, train hard, and recover.” Among his best analogies was comparing training to digging a hole.

I found this passage from “High Intensity Training the Mike Mentzer Way” by John Little to be particularly telling:

“…too often we train without ample recovery. If training digs a hole, we must fill the hole back to the top to get back to baseline. If we want to grow, we must ‘add soil’ and fully recover.”

This advice is actually more relevant in today’s culture. People are training more and harder than before, yet they’re also more stressed, sleeping less, and recovering less than ever before. The often neglected truth? You can only grow from training you can recover from.

Taken to extreme levels, Mentzer was said to only train muscles every 10-12 days. As an iron-junkie, I can’t fathom training a muscle group so infrequently, but then again, nearly every lifter would benefit from a greater focus on recovery.

Remember, your requirements for recovery increase as your strength and the intensity of your workouts increases. Stress is necessary for growth, but growth only occurs when you recover fully. Most lifters don’t recover well enough to grow as much as they could.

Heed Mentzer’s words: Abnormal strength and muscle growth require an abnormal focus on recovery.

3. Emphasize Slow, Deliberate Tension

Mentzer used slow and deliberate reps to maximize intramuscular tension and control. It was Mentzer’s belief that if you can’t pause a lift and contract, you used momentum to get there.

This is where it gets interesting. Mentzer is thought of as a “low volume” guy and, by all accounts, this is correct when you consider training volume is classically defined as “sets x reps.” But often left by the wayside is the duration of each rep, and by extension, the duration of each set.

As an example, a 5150 tempo (five seconds to lower, one second at the bottom, five seconds to lift, zero seconds rest at the top) would take 11 seconds per rep!

This means a 5-rep set would take nearly one full minute. This ALSO means a 5-rep set, which is classically considered a “strength rep range” clearly has a time under tension (TUT) duration more in line with a muscle-building stimulus.

As we’ve seen anecdotally and with research (by Hulmi et al), anabolic effectors of AMPK and mTOR are greater with hypertrophy rep training protocols than strength protocols.

When compared to the average lifter, who’s primarily focused on moving weight with no attention to tempo, the volume of Mentzer’s workouts could actually be comparable to that of a more typical program.

In this regard, even the lower-volume Mentzer routines have a lot longer time under tension with more intensity than the training of the average lifter. This may translate to a better bang for your buck in the gym.

4. Maximize Three Levels of Muscular Contraction

To trigger muscle growth, you must master all three types of muscular contraction: concentric, eccentric, and isometric.

Mentzer’s philosophy regarding the training tempos for these phases of the lift increased their intensity. Hence, the “high-intensity training” label. Here’s what he believed in doing for each:

For the Isometric

This refer to an exercise (or phase of a lift) where no shortening or lengthening occurs despite a maximal contraction. In other words, you’re firing your muscles as hard as possible, yet not moving, which allows you to maximize muscle fiber recruitment and improve your mind-muscle connection without excess joint stress. Still, this wasn’t intense enough for Mentzer.

He used both single and multi-joint exercises and various muscle positions for isometric holds. Upper-body lifts generally lasted 8-12 seconds, while lower body ranged from 12-30-plus seconds, holding a weight in an isometric contraction, often concluding with a slow negative with the aid of a spotter.

So if he were to do a bicep curl this way, it might begin with a 12-second isometric hold followed by an accentuated (slow) eccentric/negative.

Obviously, this must be done safely. Mentzer took caution in leveraging isometrics and isometrics coupled with eccentric tempos. He often programmed single-joint exercises and machine work to limit the risk of injury.

He recommended using a partner to help you lift a supra-maximal load into place at the middle of a contraction before you held the weight for time.

I wouldn’t recommend this for most people due to the risk, but you can get similar benefits by lifting a near-max weight, holding a position for 8-12 seconds on an upper-body lift (or 12-30 seconds on a lower-body lift) before lowering it down as slowly as possible.

For the Concentric

The classic “up” or lifting phase where the muscle is shortening. During this phase you’d use a variety of tempos, slow and fast.

For the Eccentric

The “down” or lowering phase of the lift where the muscle is lengthening. For this you want to use slow or long duration negatives and overload movements. Use the greatest range of motion possible to get your muscles into a full stretch. Use a slow rate of speed and tempo to create the most tension possible. Keep the load heavy to stimulate a maximum contraction.

Mentzer often used tempos such as 5150, which uses a five-second eccentric, a one-second pause on the bottom to dissipate the stretch reflex, a five-second lifting phase, and no pause at the top, which means he’d just go straight into the next rep.

Mentzer’s use of tempo is brutal. Here are a few examples using a similar tempo:

Lat Pulldown: 1X6-9 (4220)

Leg Press: 1X6-9

5. Be Patient

Mentzer was spot-on when he said, “A training method currently attributed to a champion isn’t how he’s always been training.”

In essence, don’t put the cart before the horse. There’s no need to train like a pre-contest bodybuilder, especially without a foundation of strength, movement quality, and all-in lifestyle to maximize the demands of such workouts.

The biggest mistake young lifters make? They adopt the advanced training methodologies of elite-level athletes before building a sufficient base of strength and movement quality. (I was no different, immediately starting every workout pumping my puny biceps and praying they would grow.)

In a bit of irony, Mentzer’s bitter rival, Arnold Schwarzenegger, well known for his marathon-length workouts and insane volume, is a proponent of basic total-body workouts performed three days per week… like his golden six program for beginners.

6. Embrace The “Siege” Mentality

Mentzer was equal parts intense and patient. He often preached the idea of the siege mentality: a fully engaged mindset to do battle in the gym. It was his belief that humans evolved via struggle and combat, and the gym became the modern arena for people to struggle and ultimately grow.

But the siege mentality can’t be misconstrued as a lack of patience. Mentzer preached that physique changes are cyclical rather than linear. In other words, changes in leanness and muscle growth happen all of a sudden after durations of focused work, and not linearly.

This is true. You must have the intensity to approach the gym with focus and determination, yet the patience to endure weeks and months of seemingly stalled progress. And if you punch the clock often enough, rapid changes in your physique can happen seemingly overnight.

In modern instant-gratification society, this is something we can all apply both inside and outside of the gym. Leverage patience and all-out determination in the gym. Embrace the challenge. But remember, progress is seldom linear, it’s cyclical. Those who stay the course are the ones who will succeed.

Going Heavy Duty

Love him or loathe him, Mike Mentzer was built like a brick house and willing to turn convention on its head, despite decades of pushback.

While you don’t need to agree with every piece of his philosophy, there’s something that can be learned in all cases:

  • Occasionally, dial up the intensity and dramatically reduce volume.
  • Vary your muscular contractions to maximize growth.
  • Be bold, even in the face of doubt. Above all else, embrace the siege mentality.

Make any workout work better. Fuel it.




  1. Carpinelli RN et al. Strength training. Single versus multiple sets. Sports Med. 1998 Aug;26(2):73-84. PubMed.
  2. Hulmi JJ et al. Molecular signaling in muscle is affected by the specificity of resistance exercise protocol. Scand J Med Sci Sports. 2012 Apr;22(2):240-8. PubMed.
  3. Mentzer M. Heavy Dury II: Mind and Body. Redondo Beach, California: Mentzer-Sharkey Enterprises. 1996.
  4. Mentzer M et al. High Intensity Training the Mike Mentzer Way. Chicago: Contemporary Books. 2003.
  5. Smith D et al. Strength training and the work of Arthur Jones. J Exerc Physiol. 2004;7:52-68.