Just about any method of resistance training’higher volume, lower volume, higher reps and so on’can build muscle to some extent; however, some work better than others. Furthermore, your particular muscles may grow more rapidly in response to one approach than will those of the next guy. Or the reverse may be true.
Still, there has to be a common thread, and I believe I’ve solved the mystery. I call it the ROB Concept, the culmination of my 17-year obsession with the question, What makes muscles grow?
To the extent that any training approach satisfies the ROB Concept, it will build muscle. The better your workouts satisfy it, the more quickly your muscles will increase in size. Let me start from the beginning.
When I started bodybuilding back in the summer of 1986, I resembled something akin to a lamppost. I’ve added a fair bit of muscle tissue to my scrawny frame since then (see the photos on page 138), but right from the first workout I had enormous difficulty putting on size. In hindsight it appears that I inherited a less-than-average number of muscle fibers’and the muscle fibers I did have weren’t all that interested in getting bigger. Thus, every set and every rep I performed at the gym stimulated less muscle growth than might be the case for a more genetically gifted soul’say, Dorian Yates.
Take a look at my parents, and you’ll see why. Neither my mother nor my father is, or ever has been, the least bit buff. Indeed, the Thoburns have always had to work very hard to stay in shape’and work much, much harder still to build muscle.
Yes, when they were handing out the skinny genes, I must have thought they said ‘pralines’ and asked for several servings. I was 6’1′ and weighed just over 145 pounds when my battle for buffness began.
Trial and Terror
Lots of people experiment with their workouts. Some take it to an extreme. I’m one of them. In fact, I’ve yet to meet anyone who has experimented quite as excessively as I have. Some of my workouts have been frighteningly bizarre.
I’ve tried virtually every method of weight training imaginable, including isometrics, partials, eccentric-only, concentric-only, low sets, high sets, one workout per day, two workouts per day, three workouts per day, even five workouts per day. Ridiculous, perhaps, but my Ripley’s Believe-It-or-Not’type workouts taught me some truly invaluable lessons, and this article is about the most important of them all.
Around 1993 I undertook a workout routine that started every morning at 4:30 a.m. and continued, essentially nonstop, through to 8:30 a.m. I hammered each muscle group with a total of 30 sets, three times per week. I rested 30 seconds between sets (I used a stopwatch to enforce that rule). I performed each set to momentary muscular failure using a weight that permitted eight to 10 reps.
And I overtrained, right? Right. Maybe that’s why I grew muscle as never before.
I kept up that workout routine for only a few weeks, but during that time my body ballooned to 212 pounds, and I was shredded. You could even see my pectoralis minor bursting out from my torso, clear as day’and on a guy who started out with a 33-inch chest and 10 1/2-inch arms. After several weeks I decided that if that’s the type of routine it takes for me to build muscle, that’s fine, but I’m not willing to do it. I figured I’d have to settle for being a dork. ALL Of course, I didn’t stop training. Quite the contrary’I’ve continued to experiment with my training extensively’and frequently extremely’over the years, as I have with my diet.
Two things about training that have come up time and time again: If I want to mask my skinny genes and actually build muscle at a satisfactory rate, I have to do more sets than conventional wisdom dictates. In other words, the concept of less is more for the hardgainer doesn’t work for me. Further, I will have to rest quite a bit less between sets than is typically prescribed. Simply stated, my workouts cannot be overly brief, nor can they be leisurely paced, nor can I get away with training each muscle group only one time per week.
Talk About Being Anticonventional Wisdom
Indeed, when I finally started doing what others considered over-training, and when I finally started resting only briefly (ROB) after most of my sets, I started to add muscle to my lamppost-like frame at last. Thus, at least for this extreme hardgainer, more is more.
It’s taken me more than a decade and a half to assemble the pieces of the puzzle, and I’ve still got a few spaces to fill. Most the clues have come from my own crude experimentation, although some have come from training other extreme ectomorphs and watching how they respond and others I’ve derived from studying the basics of neuromuscular physiology, biomechanics and physics.
In other words, the ROB Concept has not been proven in a lab setting and probably never will be. Nevertheless, it does explain a lot.
The ROB Concept
To the extent that any workout makes your muscles and their fibers sustain a critically high product of internal work rate x duration, they will grow. That will cause those muscle fibers to sustain a critically high product of depolarization magnitude x duration immediately afterward’the ultimate trigger of the cellular events responsible for producing muscle growth in the recovery period that follows. Let’s define some of terms.
Energy. The capacity to perform work. (Adenosine triphosphate, or ATP, is the ultimate source of energy for your muscle fibers and all other cells.)
Work. A force generated over a distance. For instance, in order to lift a weight, your muscles have to generate enough force to overcome the gravity that’s acting on the weight.
Let’s assume it takes you two seconds to perform one complete squat. If the next time you do squats you lift a heavier weight in that same time, two seconds, your quadriceps muscles will have sustained a higher overall work rate. Work rate is also known as power.
Now, if the weight is so heavy that your muscles can’t overcome the gravity acting on it, they’re still working, aren’t they? Indeed they are. The muscle fibers can’t shorten, and the contraction is isometric. No external work is done during an isometric contraction, but the muscles still work internally; that is, the constituent fibers are sustaining membrane depolarization, consuming energy (ATP) and progressively fatiguing.
Relative workload. The amount of force generated by the recruited muscle mass relative to what it’s capable of at that instant’as opposed to the at-rest state. Though absolute workload’i.e., the actual amount of weight you’re lifting’is important, it’s only important insofar as it determines how hard the recruited muscle fibers are working relative to what they’re capable of at that very moment.
Duration. The length of time the workload is sustained’i.e., how long the target muscle is trained. Why is a high internal work rate necessary?
In order for that lamp sitting on your desk to turn on, an electrical current must be transmitted from the power source to the light bulb. Then, presto, you have light.
Likewise, in order to turn on your muscle fibers’to make them generate force, or contract’your nervous system (the power source) needs to send them an electrical current. This particular current, in fact, is both electrical and chemical. It’s made up of impulses, flurries of which bombard your muscle fibers and signal them to contract.
Generally speaking, the more force that’s required to perform a given task’the heavier your set of barbell squats’the greater the frequency and size of the electrochemical impulses transmitted to the muscle fibers must be.
Trains of impulses are carried down to your muscle fibers via nerve cells, or neurons. Each muscle fiber is controlled by, or under the jurisdiction of, at least one so-called motor neuron. When a motor neuron receives an impulse train of sufficient magnitude, all of the muscle fibers it controls contract, which means they’re recruited into action. A motor neuron plus the muscle fibers it makes up is called a motor unit.
It’s All About Depolarization
When an electrochemical impulse reaches the surface of a muscle fiber, it causes the fiber membrane to depolarize. Like the battery in your car, the membrane surrounding each muscle fiber carries an electrical charge. If the charge in a car battery is dissipated, it can be used to run the starter motor, which in turn starts the engine, ultimately causing the drive train to rotate the wheels of the car. Thus, potential electrical energy’represented by the charge stored in the battery’is ultimately converted into mechanical, or kinetic, energy’the capacity to turn the wheel of the car.
The muscle-fiber membrane behaves like a battery too. During depolarization the charge across the membrane dissipates via its conversion into the mechanical work of muscle contraction. Cross-bridges form between actin and myosin protein filaments, as they slide alongside one another, and force is generated as the muscle fibers attempt to shorten. At least, that’s how contraction is thought to happen.
If you want your muscles to generate a lot of force relative to what they’re capable of at that instant, then your nervous system must recruit a lot of muscle fibers and signal each one to depolarize with a high frequency of impulses. If you don’t rest much between sets’or not at all, as in a drop set’the fiber membranes won’t have much time to repolarize, and you may achieve a sustained state of depolarization in the period immediately following. That’s what triggers muscle growth.
That last paragraph is extremely important. If you understand it, you can see why it’s not the absolute load that matters most but the relative load.
After all, it’s the relative load that determines the magnitude of membrane depolarization. And it’s the combination of the relative workload and the amount of rest’very little’you give the recruited fibers that determines the extent to which those fibers repolarize. Those factors, in turn, determine the extent of depolarization that the muscle fibers sustain after you hammer them again.
The formula for the rest you give the recruited fibers is as follows:
* between sets, very little
* between reps, it’s ROB’rest only briefly
Those points explain two very common observations:
1) You can maintain larger muscle structures’and build them even bigger’using weights much lighter than you used to lift in the past when you carried much less muscle.
2) You can still stimulate growth in a muscle group several sets into your workout, at a time when the group is very fatigued and cannot generate near the same force as it could on the first set.
The Ideal Set?
Imagine you lift a load that allows you to perform five reps before you reach momentary muscular failure. Each rep takes you about two seconds to perform, and the load requires that the recruited muscle mass generate 85 percent of the force that it’s capable of at that very moment. Now, 85 percent is a pretty high relative workload’only 15 percent shy of maximum, or 100 percent, force production. So the set doesn’t last long, and your chances are pretty good that an 85 percent relative workload will recruit most, if not all, available motor units and that those units will possibly be firing, or depolarizing, at their maximum frequency. If you don’t recruit all available motor units on the first rep, you certainly will be hitting them by the last one, again, assuming you train to failure. When you can’t recruit any more motor units and your nervous system has jacked up the firing frequency as best it can, the set comes to an end’unless you reduce the weight or take some time to let your muscle fibers recover their force-generating capacity. Imagine a load that requires you to recruit 70 percent of the force your muscles are capable of at that that very moment, thereby permitting 10 reps. That’s a lower relative workload, but you can sustain it for longer. You can do that because your force-generating capacity has to fall 30 percent before you reach failure.
Which will reward you with greater mass gains, 85 percent with a five-rep max or 70 percent with a 10-rep max? Only you can determine the answer. There is no one-rep-range-fits-all formula’at least, not one that works. That’s because genetic factors lead some people to achieve a critically high product of depolarization magnitude x duration’which yields them a maximum rate of muscle growth’at a loading/rep scheme that others find less than optimal.
That said, after decades of trial and error bodybuilders have determined that eight to 10 reps performed in straight sets works best’or at least very well’for most people. A load that lets you get that rep range likely makes the average trainee’s muscles sustain about as great a product of internal work rate x duration as can be achieved in a single set taken to initial momentary muscular failure. Thus, one set with an eight-to-10-rep maximum lets the recruited muscle fibers sustain about as great a product of depolarization magnitude x duration as possible. That’s the ultimate determinant of the growth response to training.
The Work-Rate Abyss
Let’s talk about what happens after you perform a set of squats. If you rest several minutes before performing a second set, you’ll be able to lift a heavier weight than if you rest less. The reason is that you give the muscle fibers more time to repolarize their membranes and otherwise recover their force-generating capacity.
In fact, if you rest long enough, you may be able to lift the same weight for the same number of reps as in the previous set; however, your average, or overall, work rate may actually end up being lower than if you’d rested less’even though you wouldn’t be able to lift as much. Thus, your muscle fibers will not sustain as great an overall product of depolarization magnitude x duration once you’ve finished training that particular muscle group.
Because your quadriceps aren’t generating force when you rest between sets’especially if you just sit on a bench’the longer you rest, the further their work rate falls when averaged over multiple sets. While they may work hard during the set, after they finish it, the work rate falls into the abyss.
Of course, if you don’t rest at all, you’ll have to quickly reduce the weight every few reps as your force-generating capacity falls. That’s called a drop set, or strip set.
If you do them right, drop sets can certainly enable your muscles to sustain a high product of depolarization magnitude x duration and, subsequently, get bigger. How growth responsive any muscle is to a single drop set’or a single set, for that matter’depends on genetic factors. The theory is that so many programs build muscle only very slowly because most people rest too long after a set and/or they don’t do enough sets. Not surprisingly, the human body abhors a high work rate like nature abhors a vacuum. It would prefer you read the Wall Street Journal between sets rather than rush on to the next one before your tired muscles have had time to recover. Simply stated, training quickly and intensely is tough, and we seem to have a natural aversion to it. If you give in to that aversion, however, you won’t build size as quickly as possible.
Still, most training approaches will build some muscle. That’s because they make your muscles perform some degree of work and sustain some degree of membrane depolarization afterward. Unless they address the ROB Concept fully, however, they won’t build muscle as quickly as possible. For the extreme ectomorph/hardgainer like myself, that may mean frustratingly slow’or no’progress.
The Unified Theory of Training
So, to get bigger muscles as quickly as possible, you must get them to generate a lot of force relative to what they’re capable of at that very moment, and you must not give them an extended vacation after a set. Training to failure is also very important.
Bodybuilders know that there’s something very powerful about training to failure. Sure, you can build muscle without training to failure, but you get faster progress when you do. That’s certainly been my experience. (I’ve tried stopping my sets just shy of failure, and it definitely wasn’t as effective at building muscle.)
The high relative workload’85 percent or so’ensures that my muscle fibers sustain a very high product of depolarization magnitude x duration immediately afterward.
With that technique your muscle fibers will start to fatigue from the very first rep. The very instant they begin working, they begin consuming ATP, or energy. As fatigue develops and their ability to generate force falls, your nervous system will try to recruit more muscle fibers and/or increase the firing frequency of those that have been recruited. So by the last rep or two of any set you perform to failure, all available muscle fibers will be recruited and will be depolarizing at their highest frequency.
Now you can see why training to initial momentary muscular failure and proceeding beyond that point with drop sets or forced reps can be so powerful for stimulating muscle growth.
The ROB Concept states that rest periods of 20 to 50 seconds’or practically no rest at all in the case of drop sets’is best for muscle-growth stimulation. Even so, those sets have to be performed with high relative workloads. That makes the workouts very different from endurance training, where the muscles are required to generate a low level of force. So even though you can sustain endurance training for long periods of time (sometimes several hours), the overall work rate’and, therefore, the overall product of depolarization magnitude x duration sustained once the workload is completed’is too low to generate much in the way of muscle growth. Nevertheless, some endurance athletes can maintain surprisingly large muscles while performing little or no weight training, lifting only light weights when they work out. I once had a friend who was a triathlete. He had 30-inch thighs, and they were shredded, yet he hadn’t lifted weights for years. Perhaps he had an unusually high proportion of fast-twitch fibers in his legs’and an unusually large number of muscle fibers, period. Since fast-twitch fibers achieve their maximum work rate at faster contraction speeds and lighter loads, that may explain why his 100-mile bike rides provided sufficient stimulation to keep his thighs so muscular. (On the other hand, his fast-twitch-dominant fiber composition may have prevented him from being a champion long-distance cyclist.) If I were to train legs his way, mine would waste away to nothing. I know, as I’ve tried.
Do You Have Bad or Good Muscle-Building Genetics?
The three most important genetic determinants of muscle-building success are:
1) Number of muscle fibers. In other words, how many muscle fibers are there in each of your muscles? The more you have, the more growth you’re capable of stimulating with every rep.
2) Size of muscle fibers. How big is the typical fiber in a given muscle? Having lots of tiny fibers can be better than having a smaller number of bigger fibers. All muscle fibers have a size limit. The bigger the fiber is, the closer it is to that limit and the less potential it has for growth. Furthermore, it may be harder to make muscle fibers with larger diameters sustain a high product of depolarization magnitude x duration.
3) Composition of muscle fibers. What percentage of your fibers in each muscle are fast twitch vs. slow twitch? Slow-twitch fibers are more resistant to growth. If you want muscles that are big, fast-twitch is the way to go. Ideally, you’d like to have a lot of small fast-twitch fibers. Unfortunately, you don’t have a choice in the matter.
Extreme ectomorphs are usually hardgainers because they got a raw deal on all three factors.
Fiber Type and the ROB Concept
Remember the frequently quoted recommendation to train slow-twitch fibers using higher reps (e.g., 12 to 15) and lighter loads? Well, you may need to forget it. Fast-twitch fibers contract more quickly than slow-twitch fibers. Consequently, they reach their maximum work rate at a faster contraction speed, which, as discussed, occurs when you use a lighter weight. Physiologists call that the force-velocity relationship, and it can be illustrated on a curve (the so-called force-velocity curve).
Resting a long time between sets may enable you to lift heavier weights, but those weights may keep the fast-twitch fibers from achieving their maximum work rate. Plus, the longer rest periods will make your overall work rate undesirably low for the purposes of building muscle. Remember, you’re not trying to break strength records here. The ROB Concept is for muscle-building only, though you can certainly get a lot stronger by incorporating it into your workouts.
Slow-twitch fibers contract more slowly than fast-twitch fibers. Consequently, they reach their maximum work rate at a slower contraction speed, which occurs when you use a heavier weight. Furthermore, since slow-twitch fibers are more resistant to hypertrophy, they may need to sustain a high work rate for a longer period of time. In other words, you may need to pound them with more sets. [Note: Some scientists suggest that slow-twitch fibers may be better stimulated to grow with maximum-force isometric contractions. You can read more about that in The ROB Report, and at my Web site.]
As you can imagine, it can take considerable experimentation to figure out how many sets you need to do for each muscle group in order to see changes in the mirror at a satisfactory pace. If you’re like me, you may require a lot more sets than the less-is-more proponents prescribe. Those who have been blessed with good muscle-building genetics will say that’s overtraining, but for most hardgainers, programs that work for genetic superiors would constitute undertraining.
Internal vs. External Work Rates
There’s a big difference between external work rate (or power) and internal work rate. External work rate is essentially how much weight you lift over time. Internal work rate refers to how hard the muscle fibers are working, both at the level of membrane depolarization and within the muscle fiber itself. How fast is ATP being broken down per unit of time? How fast is sodium accumulating inside the muscle fibers? How fast is potassium accumulating outside the muscle fibers? How fast are hydrogen ions and lactate accumulating? Those are the important things for building muscle.
The distinction between internal and external work rates is extremely important. For instance, you can lift more weight during the top few inches of a squat or leg press because your mechanical advantage is better, but your muscles actually work less there because the leverage is better. The point is you want your muscles to work as hard as possible. If muscle size is your goal, don’t let your ego get caught up in external work. Focus on internal work.
Again, the need for experimentation is inevitable. That’s what I love about the ROB Concept. Rather than being an approach in itself, it’s a very powerful principle that applies to very many different workout approaches, and it explains why some work better than others and why some people respond better to a given approach than do others. In effect it is the unified theory of bodybuilding training. How to Incorporate the ROB Concept Into Your Workouts
It’s practically impossible to determine what combination of loads and rest intervals will enable the muscle fibers of any given muscle to achieve the greatest overall product of membrane depolarization magnitude x duration afterward. We also don’t know when that product has been achieved until you go home, recover and then do it all over again.
Are you beating a dead dog after performing 10 sets or three drop sets for a given muscle group, or can you stimulate further growth? Is it worthwhile to go back to the gym and train the same muscle group again two days or even one day later before the myofibrillar protein synthesis stimulated by the previous workout has returned to normal? Those are questions that have yet to be answered. The answers may differ for every person and, perhaps, every muscle group. While I’d love to tell you that there are specific guidelines’number of sets, rest between sets and so on’there aren’t. I only know what works for me, and even that is continually evolving, as you can tell if you follow my training and eating diary at my Web site. So for now you’ll have to go by trial and error. Even if you knew how many fibers you had in each muscle and what the fiber composition was, you’d still have to experiment. For instance, if a certain combination of reps and rest-interval length is optimal for stimulating fast-twitch fibers and another combination is optimal for stimulating slow-twitch fibers, will it really make a difference if you perform five sets of each approach rather than 10 sets of an approach that meets each fiber’s needs half-way? It may. Experiment, but stick to the basics of the ROB Concept. [See ROB Concept Sample Workout below.]
ROB Concept Sample Workout
1) Warm up completely. That’s very important. Hop on a treadmill and run as hard as you can for three to four minutes. Or pedal on a stationary bike. The higher your work rate, the more quickly you’ll break into a sweat and lube up your muscles and joints for the iron pumping to come.
2) Use predominantly, if not exclusively, the compound exercises. Pick one or two movements for each major muscle group. Isolation exercises are less effective, but sometimes you don’t have a choice. Here are some recommendations:
Quadriceps: barbell squats or leg presses (squats are better)
Hamstrings: barbell stiff-legged deadlifts or lying leg curls (deadlifts are better)
Calves: standing calf raises
Back: barbell bent-over rows or wide-grip pullups (with weight as necessary; palms facing forward, slightly wider than shoulder-width grip)
Biceps: standing barbell or dumbbell curls
Chest: barbell flat-bench presses
Shoulders: barbell or dumbbell presses for the front heads; barbell or dumbbell upright rows for the side heads
Triceps: barbell close-grip bench presses or parallel-bar dips (with weight as necessary)
Abdominals: crunches (with weight behind head as necessary)
The so-called compound exercises tend to stimulate more muscle growth per rep, and they also burn more calories per rep than isolation movements. They’re harder, too, but program your mind to associate pleasure with the rewards you’ll get from giving them your all. Of course, some muscle groups can only be trained with isolation exercises’e.g., calves and abs’so you’re off the hook on them.
3) Do eight sets per muscle group, not including warmup sets.
4) Lift as much weight as you can for five to eight reps on all work sets.
5) Rest 20 seconds between sets’no more, no less.
6) Important: Do your absolute best to use a progressively heavier weight for your first work set on every exercise. Write down the poundage you use so you have a record. You’ll then be much more compelled to exceed it at your next workout. When you can do eight reps, increase the weight by five pounds at your next workout (10 pounds on leg exercises).
7) Train each muscle group two times per week. After three to four weeks increase your frequency to three times per week.
8) If your workouts take you less than 60 minutes, fill in the gap with intense cardio. Run on a treadmill or pedal a stationary cycle at the highest work rate you can for the rest of the hour. You should be training at least an hour a day.
9) You can structure your workouts however you like; just make sure you satisfy the above guidelines. Here’s a sample split:
Day 1: Chest, shoulders, triceps
Day 2: Back, biceps, abs
Day 3: Quads, hamstrings, calves
10) Take a day off only when you feel it’s absolutely necessary. If that’s every 10 days, so be it. There’s no one best way to schedule days off. Just don’t sell yourself short. Many people mistake lack of willingness to push their muscles hard for overtraining. It’s surprising how hard and how frequently you can train your muscles without going too far.
If you commit yourself with 100 percent effort, I guarantee that within four to six weeks you’ll see new muscle tissue sprouting all over your body. Remember the ROB Concept: To the extent that any one of your workouts makes your muscle fibers sustain a high product of internal work rate x duration, the fibers will be in a state of sustained depolarization, and they will grow. The greater the extent of that postworkload depolarization, the more growth you stimulate.
Editor’s note: Visit Robert Thoburn’s Web site at www.robthoburn.com. The ROB Report’the World’s Greatest Source of Real and Original Bodybuilding Information’is available there, along with further discussion of the ROB Concept. IM