10 False Beliefs about Muscle Growth

When You Dont Know What you Dont Know

Ive said before that Fitness and health knowledge is the BEST its ever been, a golden age even. For as much as I critique modern scientism, good science is still being done, and the past decade in exercise science has been explosive. 

One area that has gone through a real revolution is understanding muscle growth

Humans have always fundamentally understood what makes for a strong body. I wrote about this in my Ancient Athletics guide. 

We KNOW that being good at moving fast and explosively makes someone strong. 

We know that being able to move heavy objects, whether its weights or another human, that makes someone strong. 

We know that to improve these qualities, we must practice them. 

This is all axiomatic. 

But the specific mechanisms, thats taken a long time to study. 

It wasnt until the 20th century that we had molecular science and could study the body thoroughly on a cellular level. 

For Muscle and strength gains, there were lots of theories and beliefs that arose over the years

10 Beliefs and Theories about Muscle Growth

1. You need to damage your muscles as much as possible for them to grow

2. Free weights build more muscle than machines 

3. You can use short rest periods to increase growth hormone, and this will make muscles grow

4. Time under tension is what causes muscles growth

5. Heavy weights build more muscle than light weights 

6. High reps dont build muscle, they only are far endurance

7. Exercises like squats and deadlifts boost your testosterone, and increase your muscle growth

8. A muscle wont grow unless its sore and fatigued after a workout 

9. Muscles cannot grow unless you have a Mind-Muscle Connection 

10. Chasing the pump (get a muscle filled with as much blood as possible) is how you build muscle 

Which of these are True? 

NONE OF THEM

I know some of you are scrunching your eyebrows and experiencing cognitive dissonance. 

"What do you mean they are WRONG?!" 

I will clear up the confusion, I promise

To make sense of what I am about to say, understand that based on decades of research and multitudes of study (replicated studies for that matter), there is only ONE FACTOR that matters for muscle growth and strength gain

-Meaningful mechanical tension that fatigues muscle fibers 

Meaningful means heavy enough, and done for enough reps, to challenge the fibers ability to contract. If you meet a minimum threshold of stimulus and do enough growth stimulating reps over the course of a set (or multiple sets), your muscles will grow

And thats it. 

10 Truths about Muscle Growth

1. How much you damage your muscles is a side effect of training, not a cause. Research has shown that the MORE a muscle is damaged, the less it actually grows. Some damage is inevitable from training, but trying to create more has the opposite of the intended effect

2. Free weights and machines build equal amounts of muscle, when joint ROM and strength curves are matched. Your muscles dont know what you are lifting with, all that matters is their ability to produce force and how much mechanical tension is being placed on them

3. Longest rest periods lead to MORE muscle growth and strength gains. Short rest periods have the opposite effect. Muscle and strength will still happen, but less than if you had rested longer. This is because your force output gets reduced with fatigue and incomplete recovery 

4. Time under tension by itself does not stimulate growth. The tension must be HEAVY. Its true that more meaningful tension from doing more reps can stimulate more growth, but TUT by itself is a proxy factor, not a primary cause. 

5. Heavy weights and light weights build the SAME amount of muscle, provided sets are done to failure. This is because its only the last 5 or so HARD reps of a set that are stimulating for muscle growth

6. Muscle growth can be seen with sets as high as 20, 30, and in some studies even 40 reps. High reps are not an efficient way to train, but they certainly build muscle when done correctly 

7. There are no special exercises that "boost" testosterone and lead to more muscle growth. Any kind of lifting done with strenuous exercise and training multiple muscles can lead to acute testosterone increase. But this increase is not enough to meaningfully lead to more muscle growth to begin with. 

8. The greater the muscle fatigue from training, the less muscle growth is seen. Its paradoxical, but for maximum muscle growth, you want to stimulate as much as possible, but limit fatigue as the same time. There is a law of diminishing returns. in effect with how many sets you do per workout, and per week

9. If you can move a joint and perform an exercise through a given ROM, that muscle is working, regardless of whether you are able to acutely feel it. The ability to acutely feel a muscle depends on the exercise (you will ALWAYS feel a muscle more when training isolated versus compound) and how long you have been training. 

10. While bloodflow is important for lifting performance and a pump is a positive indicator you are training the target muscle, its not causing growth. Again, its a proxy effect. You could pump a muscle with lots of reps and sets, but if the weights arent heavy and the sets not intense enough, that muscle is not going to grow. 

Maybe that sounds confusing, but if understand it holistically, it simplifies the training Process

To grow muscle and get stronger ,you must lift heavy weights for more for more reps over time, with proper technique, on productive exercises. 

Heavy weights can be 5-8 reps, 6-10, 8-12, 10-15 it does not matter what rep range you choose, that is individual and relative to the exercise, workout, and your body. 

The rep range is relative, what matters is the reps increase with time, and the weights increase with time. 

Productive exercises means exercises you can perform for more reps and more weight over time, with a full ROM. Exercise that work for you based on your body.

All the other factors are secondary. 

I would encourage all of you to read my "Workout Rules and Recommendations 2023" if you have not already. 

and If you are still confused, buy a program, I suggest starting with Push Pull Legs, and Learn by Doing