The Key to Continuous Muscle Growth

How to Avoid Training Immunity

Here’s what to do when your training plan stops working. And it will stop working.

Every Training Program Works… Until It Doesn’t

It doesn’t matter how much you love a certain program. It’s physically impossible to keep progressing on it forever.

The fact is, if you want long-term progress you’ll need to increase the demands of your training program. But how? Do you gradually increase volume? Do you focus more on intensity? Add more weight to the bar? Or is it something completely different?

“What should I do next?” is the most important question you’ll ever ask when it comes to achieving your full potential.

The Solution: Change The Type Of Stimulus

Volume, intensity, and progressive overload are important, but they can’t be the long-term answer. All three have their champions:

  1. The volume camp says that when the body adapts to physical training you need to increase the overall amount of work to force it to continue adapting.
  2. The progressive overload crew says you need to focus on gradually adding weight to the barbell.
  3. The high intensity team says the key to hypertrophy is going to failure, then there’s no real need to worry about adding weight (you should when your sets get too easy, but it’s not the main goal).

Well, they’re all wrong… but also right in some regards.

The most important thing for continuous progress is NOT doing more and more volume. It isn’t adding more weight to the bar every week either. And it’s not taking your sets deeper down the high-intensity hole.

It’s frequently changing the TYPE of stimulus you impose on your body.

Volume, intensity, and load increase the magnitude of the stimulus. But if you stay with the same program, you’re still providing the same stimulus. Eventually the body becomes fully adapted to it. At that point, your body is essentially “immune” to the training.

You do your workout, it creates fatigue, and it might even give you a good feeling. But afterwards it only brings you back to the same level at which you started.

You can’t increase volume forever. Will you, at some point, have to do 100 sets per muscle group to keep gaining?

Progressive overload isn’t any better. You can’t keep adding weight to the bar forever. If you start with a 250 pound bench, only adding five pounds per week would give you a 500 pound bench after a year. Afterwards, even if you could only add a pound per week, you’d still be benching 1000 after ten years of training. How many people bench 1000 pounds? Heck, how many bench 500?

It’s the same with intensity. While you can add strategies to go beyond failure (rest/pause, drops set, partials, etc.) at some point you can’t hit failure ten times in a single set. The body won’t be able to take it.

All of these variables are finite. The only thing you can constantly change is the nature of the stimulus.

For muscle growth, the key to long-term progression is changing the stimulus imposed on your body. This means changing HOW you do your sets – the tempo, the special methods, the intensity of work, the zone you’re training in, etc. The more you change the type of stimulus, the less you need to increase the strength of the stimulus.

Of course, these changes have to be planned in a smart and progressive way. And they still have to make the body work gradually harder.

Adaptation, Trainability, and Training Immunity

Your body doesn’t want to add muscle. It’s metabolically expensive and it’s costly to build and maintain.

You won’t add muscle unless your body deems it to be absolutely necessary. You do that by imposing physical stress (training) onto your body that it’s not used to facing. If your body isn’t used to that stress – and not adapted to it – the more trainable the body is.

“Trainability” is your potential to improve in response to certain stress. Every time you repeat the same type of stress, your body becomes more and more adapted to it, which decreases its trainability. Every time you repeat a certain type of stress you make that workout less effective.

If you repeat that type of training often enough, you will become fully adapted and there won’t be any need to grow bigger. This is what I call “training immunity.”

Adapting to Workouts… and the Sun

The variables that influence the characteristics of a workout determine the type of physical stress you’re imposing on your body. Those variables could be rep tempo, the use of isometric holds, pure concentric vs. normal reps, changing the strength curve with chains/bands, the intensity zone, rest intervals, the exercises you use, etc.

Volume, intensiveness (how hard you push each set), and the amount of weight used don’t change the type of physical stress; they only affect its magnitude.

I’ll use sunbathing as an example. The sun is a stimulus. If you go tanning at 1 PM on a bright, sunny day, the sun will be stronger than if you go at 4 PM or if you do it on a cloudy day. But it’s still the same sun and the same type of stimulus.

Same thing with the duration. If you go out in the sun for four hours you’ll put a stronger stress on your skin than if you only stay for 20 minutes. But it remains the same type of stress: sun exposure.

If you go tanning when the sun is at its strongest, or if you stay longer, you’ll get a tan faster. But once you have the deepest tan you can get, you won’t be able to get darker regardless of how long you stay in the sun or how intense it is. How dark you can get is largely genetic, just like how much muscle you can build.

It’s the same thing with training. You do a certain workout and it triggers adaptation and growth. The more you repeat that workout, the weaker the stimulus becomes.

You can make the stimulus stronger by doing the same training but with more volume, pushing your sets harder, or adding weight. This increases the strength of the stimulus and you’re able to progress again.

But here’s the catch-22: Increasing the strength of the stimulus actually speeds up your habituation to a certain type of stress. Just like sunbathing for longer will get you to the maximum tan you can get sooner.

Here’s the difference between getting a tan and building muscle: There’s only one type of stimulus that can give you a tan, but there are several pathways to trigger muscle growth.

This means you can change the type of physical stress you put on your body by training. How? By changing things like the tempo of your reps, the type of contraction, the strength curve, the training methods, the tools you use, or the exercises you perform.

Planned Variation: The Key to Long-Term Progress

The more foreign a certain physical stress, the stronger it is and the less you need to increase its magnitude with high volume or high intensity.

I’m not saying you shouldn’t train hard when the stimulus is new, but that you don’t need to push volume, intensity, and loading to the extreme to stimulate gains. I’ll give you three examples.

  1. Years ago, I decided to try gymnastic-type training, mostly focusing on ring work. The first three weeks of doing it I had significant changes to how my body looked. But after that, the physical changes stopped. At one point I was doing up to four hours of training per day and actually regressed from a “look” perspective.
  2. The same thing happens every time I start using the Olympic lifts. I get a sudden improvement in body composition. But the rapid changes that occur in the beginning are simply due to the physical stress being so different that it leads to quick improvements. But this rapidly subsides.
  3. I once tried CrossFit for three months. (I trained a lot of CrossFit athletes and wanted to understand the demands of the sport better.) Again, in the first few weeks my body started looking better and better… but very little happened after that.

No, you don’t have to rotate bodybuilding, gymnastic work, CrossFit, and Olympic lifting. I’m just illustrating that dramatically and frequently changing the nature of your training can help you progress faster, for longer, and without having to resort to extreme volume or intensity increases, which can be impractical and unpleasant.

How Often Should I Vary My Training?

The less experienced you are, the longer you can stay on the same program. Your body is so far away from its maximum potential that any type of training provides a very strong stress/stimulus. Newer lifters can use the same type of training for 12 weeks, although I still prefer to have some variation every six weeks.

The more experienced you are, the more frequent and contrasted the changes need to be. I like to change workouts every three to four weeks. Very advanced individuals like pro athletes might even need to rotate every two weeks!

What Do I Change?

Some variables will have a stronger impact than others. Look at exercises.

Essentially, all exercises do is “decide” which muscle receives the physical stress. As such, if that’s the only thing you change, it actually has a limited effect on the type of stimulus. For example, if you switch from a barbell bench press to a dumbbell bench press (and keep the same tempo, method, and rep zone) you’re not really changing the type of stress that much.

Changing exercises and keeping other variables the same is good for mostly neurological improvements. While this is useful for strength, it’s not your best option for maximum muscle growth.

Here are some of the most powerful ways to change your training and get better long-term growth:

1. Lifting Zone

A lot of coaches call this rotating between accumulation (higher volume, lower weights, higher reps, longer time under tension, shorter rest intervals) and intensification (lower volume, heavier weights, lower reps, shorter time under tension, longer rest intervals).

If your goal is to build muscle, you don’t need to go “powerlifting heavy” with sets of 1-3 reps. Your intensification phases could focus on sets of 4-6 and 6-8 reps whereas your accumulation phases could use sets of 12-15 and even 15-20 on smaller exercises.

2. Tempo

This includes everything that has to do with how each rep is performed. You can slow down the eccentric/negative, include isometric holds during the set or even during every rep, or even slow down the concentric/lifting phase.

For maximum effect, the changes should be drastic. For example, if you use a tempo of 4010 (4 seconds eccentric, 1 second concentric) for three weeks, then go to 5010, that’s not much of a change. But going from 2010 to 6010 will make a big difference.

Here’s an example of how you could vary tempo from phase to phase:

  • Weeks 1-3: 2010 (normal tempo)
  • Weeks 4-6: 6010 (6 second eccentric)
  • Weeks 7-9: A 3-4 second isometric hold on each rep during the eccentric phase
  • Weeks 10-12: 4030 tempo (4 second eccentric, 3 second concentric)

The goal is to maintain the same weight in each phase. For example:

Phase 1 (2010 Tempo)

  • Week 1: 200 x 6
  • Week 2: 205 x 6
  • Week 3: 210 x 6

Phase 2 (6010 Tempo)

  • Week 1: 200 x 6
  • Week 2: 205 x 6
  • Week 3: 210 x 6

Phase 3 (Stato-Dynamic)

  • Week 1: 200 x 6
  • Week 2: 205 x 6
  • Week 3: 210 x 6

Phase 4 (4030 Tempo)

  • Week 1: 200 x 6
  • Week 2: 205 x 6
  • Week 3: 210 x 6

In each phase you make the sets harder. If you can keep using the same weights you’re imposing a gradually greater stress on the body.

3. Resistance Curve

The resistance curve refers to how the resistance changes during the exercise. For example, with a barbell the resistance stays the same throughout the movement, but if you add bands then the resistance increases as you progress through the range of motion.

Some machines will also vary the resistance curve during the movement, as will weight releasers which add weight during the eccentric phase but not during the concentric phase.

While playing with the resistance curve can be detrimental for motor learning, it can still be used every once in a while to provide a pretty strong change in stimulus.

You can add chains to the bar, resistance bands, or use the reverse-band method. John Meadows found that adding bands to hypertrophy training was very effective for three weeks, but stopped working after that.

4. Training Methods

This refers to how you’re performing each set. Examples:

  1. Rest/Pause: Perform reps close to failure, rest for 10-20 seconds, and then do as many solid reps as you can with the same weight.
  2. Drop Sets: Perform reps close to failure, reduce the weight by 20-50%, then do as many reps as possible with the new weight.
  3. Mechanical Drop Sets: Use variations of the same exercise in each set. For example, doing a pronated dumbbell curl, then a supinated dumbbell curl, then a neutral dumbbell curl. Start with the weaker exercise. When you’re close to failure, switch to the second strongest movement. Finish by switching to the strongest variation and do as many solid reps as possible. Ideally, take 10 seconds or less between variations.
  4. Pre-Fatigue Superset: Combine an isolation exercise and a multi-joint movement as a superset. Start with the isolation movement for one of the muscles involved in the main lift, then move on to the big lift.
  5. Post-Fatigue Superset: Start with the big lift and finish with the isolation exercise.
  6. Clusters: Perform your set by resting for 15-30 seconds between reps (rack the weight between reps). This allows you to use more weight than you would for that number of reps if done as a regular set.


A good example is performing rack pulls from below the knees or a bench press from pins starting at the “elbows at 90 degrees” position in the power rack. This allows you to use a lot more weight than you normally would be able to do in the full range movement.

You can also use this method with more isolated movements, only performing the part of the ROM with the greatest tension. For example, doing dumbbell lateral raises from the mid-range point up to the finish position, or dumbbell flyes from the bottom position up to the mid-point.


This could be an exercise change, like going from a barbell back squat to a Smith machine squat, or using dumbbells instead of a bar for bench press. Or the changes could be more minor, like going from a bench press with a regular bar to a bench press with a thick bar.


The physical and neurological state you’re in when performing an exercise has an impact on the stimulus that movement will provide to the body.

Example: If you start your workout by killing your quads on leg extensions then move on to back squats, the effect will be different than if you started with the squats. It’s not just because you’re more fatigued – the nervous system will tend to use muscles differently because one of the prime movers is trashed while the others are rested.

Traditionally, we start with the bigger/heavier movements and work our way toward the more isolated stuff. But we can see plenty of examples of people achieving success by doing the opposite. For example, Dorian Yates doing deadlifts at the end of his back workout.

Doing a slow eccentric under tension when the muscle fibers are already tired and the muscle is filled with fluids will have a different effect than doing the same eccentric with a fresh muscle. Exercise order matters.

Which Approach Should I Use?

As long as you introduce frequent variation, it likely doesn’t matter that much. However, I like to use variations both within a training program/phase and from program to program.

For example, you can change your program every four weeks but also include variation from week to week within a program. You can change the tempo every week in your program. You could even change the training methods every two weeks. Heck, you can combine both!

For example:

  • Week One: 3 x 8-10 reps using a 3010 tempo
  • Week Two: 3 x 8-10 reps plus rest/pause using a 3010 tempo
  • Week Three: 3 x 8-10 reps using a 6010 tempo
  • Week Four: 3 x 8-10 reps plus rest/pause using a 6010 tempo

The more advanced you are, the greater the variation needs to be from program to program. If you can use two, three, or more sources of variation from program to program, you’ll have a better chance of stimulating new progress.


The training stimulus imposed on the body must be stressful enough to force the body to adapt. The more variation you include, the more you create a novel stress, the less you need to rely on quantitative measures (volume, weight, intensity) to increase the stress enough to trigger adaptations.

Yes, you should still employ weight increases and even volume addition to increase the magnitude of the stimulus. But they should be the secondary sources of stress behind variation.

Increasing volume, especially, should be a last resort because the body has a limited capacity to recover from training stress, especially the natural body.