Why can’t I build muscle even when I lift heavy & eat everything in sight?

There are a lot of reasons for that! We’re good at building muscle, but we’re not necessarily good at gaining weight. The 2005 study looking into muscle-building genetics—the one that found that skinny guys had a genetic gift when it comes to building muscle—well, they disqualified all the participants who weren’t gaining weight, since without weight gain you can’t build muscle (study).


Us naturally skinny guys are great at building muscle when gaining weight, but as you know all too well… weight gain is really damn tough when you’ve got a skinny guys stomach and metabolism.

This is made harder still because every single popular mainstream diet was created for chubby people trying to lose weight (97% of the population). Even most of the diets masquerading as manly muscle-building diets are weight loss diets!

For example, Paleo is all about lean muscle, but it restricts the types of foods that are easy to overeat (grains, dairy, sugar, carbs), making it hard for us to get into a calorie surplus. Another good example is intermittent fasting. Intermittent fasting is also seemingly all about muscle, but it restricts the number of meals you get to eat, making it nearly impossible to squeeze enough calories into an even shorter timeframe (study).

If you want to learn more about why our stomachs are small, our metabolisms are monstrous, and what you can do about it, check this article out: The Skinny on “Just Eat More”

The other challenge is working out. What skinny guy wants to go a gym? That’s, like, the only place in the world where you’re judged solely based on the size of your muscles. That’s our worst nightmare. So we instead tend to prefer types of exercise that we feel we’re better suited for.

The problem is that those types of exercise will only result in a muscular physique if you’re naturally muscular—if you already have the muscle on your body, perhaps hidden away under layers of fat.

Endurance training (e.g. jogging) causes endurance adaptations—more blood vessels, better oxygen delivery, better glycogen storage, a higher red blood cell count, etc. Great things, but they aren’t at all related to muscle size/strength.

General fitness training marketed to a general audience—p90x, Insanity, callisthenics, tough mudder-y stuff, CrossFit—is still mostly weight loss training, because 97% of people are trying to lose weight. With these programs there’s more emphasis on general fitness, not just muscular endurance. Still, these adaptations are mostly related to oxygen delivery. Capillary density and blood flow—that kind of thing. When you feel tired—even when your muscles feel tired—this is more of a central nervous system “fitness” thing, not an indication that you’ve stimulated your muscles in a way that will cause muscle growth.

If you want to learn more about what types of exercise will cause you to adapt by building muscle, check this article out: The Skinny on “Just Lift Heavy”

The good news is that if you combine a hearty muscle-building diet with a hearty muscle-building weightlifting program, you’ll be able to build muscle more rapidly than any other body type (study).

How to build muscle and gain weight as a skinny guy / ectomorph

Category: 1. Skinny Guy Problems

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