A narrative review published by Van Every, Lim, Wolfe, Knippard and Phillips Several popular but poorly supported theories regarding what actually causes muscle growth were critically examined.
Modern day fitness often focuses on conditioning, and with that we sometimes lose sight of the things that really matter. This is “shiny object syndrome”, except for programming techniques and fancy exercises instead of hobbies and ideas.
Backed by scientific research, the review debunks three myths about muscle growth.
Myth 1 – Post-workout hormone spikes play a factor
After a vigorous workout, you will experience an increase in testosterone, growth hormone, and IGF-1. However, evidence suggests that this is primarily a byproduct of resistance training rather than an actual link to muscle growth.
Furthermore, these hormonal spikes are short-lived.
Myth 2 – “Pump” directly causes muscle growth
As announced by Arnold Schwarzenegger pumping ironThe biggest feeling in the gym is the pump. Blood rushes to the muscles and your skin tightens as you admire this temporary position in the mirror.
Unfortunately, it has little effect on muscle growth. Cell swelling, as reported in the literature, has the weakest correlation with hypertrophy. Other factors are far more important.
Myth 3 – Metabolic stress (ie inflammation) causes muscle growth
Metabolic stress and pumps often go hand in hand. A high repetition set, superset, or circuit style training floods your muscles with blood while also causing irritation known as metabolic stress.
This irritation results from the accumulation of metabolites, which some believe may indicate muscle growth. Unfortunately, research says otherwise.
One reason this theory fails is that endurance training causes a similar response, and we know this type of training is not conducive to building muscle.
(Photo by Owen Humphreys – PA Images/PA Images via Getty Images)
What actually builds muscle?
Now that we’ve cleared up some of the misconceptions surrounding muscle building, let’s dive into the real drivers of hypertrophy. The answer is simpler than you might think, and that simplicity explains why it can be overlooked.
Mechanical stress is the primary driver of muscle growth.
In simple terms, mechanical stress means placing the muscle under sufficient resistance, forcing it to adapt and grow. It can be dumbbells, barbell, kettlebellsCables, machines, whatever.
Adequate resistance to mechanical stress is required so that the exercise is challenging, and good form to ensure that the target muscle is being worked effectively. This fundamental principle has stood the test of time not only through anecdotal evidence but also through scientific research.
The good news is that you don’t have to chase fancy training routines or try to create a perfectly optimal hormonal environment.
An important aspect of mechanical stress is that it changes. The weight that was challenging for you as a beginner will become easier as time goes on. Unless you make progress, you can’t expect the same results, whether it’s more weight, more reps, or both.
Basics aren’t sexy. They are not new. They are not exciting. But they work.
This story was originally published by men’s fitness On February 19, 2026, where it first appeared news Section. Connect men’s fitness as one Favorite source by clicking here.
