Lose Weight
Header image featuring woman eating, sleeping, and working out

This is page five of a How to Build Muscle guide. Start with page one to understand how realistic it is to build more muscle.

The science of losing weight quickly

This page summarizes the research on how to lose fat while also building muscle. (Spoiler: It mostly boils down to self-control.)

Whether losing fat before or after building muscle, this page is a full reference.

Why you fail to lose weight

Although I’m sharing straightforward advice for losing weight, the majority of overweight readers will not accomplish their fat loss goals after reading this.

Typically, you become overweight and stay that way due to a lack of will, a lack of self-control, and a lack of diligence. Not because you didn’t have access to weight loss dieting advice. 

Everyone knows how to lose fat if they wanted to: exercise more and eat less.

And, no, you're not  fat just because of a “slow metabolism” (unless you have hypothyroidism). In fact, genetics play a small part in propensity for obesity. And that predisposition is neutralized by living even a lightly active lifestyle (article). 

To repeat: Having “bad genetics” won't make you fat if you’re living and eating well.

Granted, many overweight people have the self-control when it comes to eating, but they lack the diligence to lose the weight because they don't realize how many calories they're eating in a day.

Research shows that overweight people chronically underestimate their daily calorie intake (study). Either because they don’t know how many calories are in their meals, or they don’t realize how often they eat.

And, let’s be honest, after a long day's work, who would want to stick to a diet? You want a pick-me-up — and a delicious, high-calorie meal does the trick.

But, when that happens with fit people, the difference is that they say "no" more often than overweight people do. They don't cave every time. And when they do cave, they don't go crazy with overeating.

Plus they're consistently exercising to lose weight. It's not on and off.

Before we continue, know I’m neither a doctor nor a nutritionist (disclaimer), so this is not professional medical advice. Consult a doctor to address your exact needs. As one example, if you’re suffering from anxiety that triggers compulsive eating, you'll need to talk to a therapist. Crack open Yelp and find someone.

On a chemical level, most people are mistaken about how fat is actually lost. Check out this awesome TEDx talk for some scientific insight:

Wait, how do I build muscle?

If you landed on this page and are new to this guide, start with part one: It introduces efficient muscle building plans for both men and women.

← Start with part one

When to lose weight

You can lose weight before or after you build muscle.

Don't try to lose a lot of fat while on a muscle building program because it conflicts with calorie requirements for muscle gains, and it will make arm muscle measurements invalid because your arms will simultaneously shrink from fat loss.

If you’re ~25lbs+ (11.34kg+) overweight, consider losing the fat before this program so your weekly muscle gains will be more visually evident to you. That keeps you motivated. The less fat you have, the more your muscles show.

Another reason to lose weight upfront is that losing a significant amount of fat in a short time also reduces muscle mass. We don’t want to lose the muscle we’re working so hard to gain on this program.

Use the calculator below to roughly estimate how overweight you are:

Height — (move slider)
Weight — (move slider)

BMI Classification

If you only have a bit of fat and you’re not in a rush to lose it, lose it after this program ends. (If you choose to lose fat at all.) This is because you’ll likely gain a couple pounds of fat from this bodybuilding program due to the strict calorie requirements, so you might as well lose all the fat at once.

These two before and after approaches to weight loss differ significantly:

Tip: Make sure you own a scale. Fat loss will is not visually evident week-to-week, so if you don’t have scale readings to prove you’re losing weight, you can lose motivation.

Pre-muscle weight loss plan

First, a reminder: Consult a doctor for a health checkup and professional dietary advice before beginning a weight loss program. If you take medications or have injuries, a weight loss plan might be dangerous without professional medical input.

Now, let's get to the advice.

A fascinating study showed that reducing hunger is the most effective way to avoid overeating (study). This seems obvious at first, but it’s really not: Reducing hunger means playing tricks on yourself to reduce your appetite throughout the day. 

With that in mind, here are my tips for how to lose weight:

Here’s a recap of the above. Follow this closely if you want to lose weight fast:

For most people, these rules will reduce the desire to overeat. 

But not overeating isn’t the only goal. We also have to restrict calories if we want to lose weight. To do this, we decide if we want to run a deficit of 500 or 1000 under our daily calorie target.

Deciding how quickly to lose weight is a matter of discovering how much undereating you can tolerate on a sustained basis. Test 500 calories then consider 1000 once you're disciplined.

(We're glossing over calorie counting and meal formation here because these topics are covered extensively in the nutrition section of this guide.)


Before we move onto the post-workout fat loss process, let's discuss exercising to lose weight.

Cardio is always a good idea, but it is not required.

When undereating, you’ll still lose weight quickly even if you don’t exercise. But if you’re looking to lose weight even faster, hit the treadmill a few times a week:

Off topic, to read handbooks (like the one you're reading now) a few months before I publish them, you can provide your email below. I'm releasing how to write fiction, think critically, and play piano. I only email once every three months.

I have another handbook that's already been released: Startup Marketing.

Bonus video


Post-muscle weight loss plan

This post-weightlifting fat loss plan is for those who already have their eating under control — and just need specific instructions for how to gradually lose fat while building muscle.

The reason we must lose fat slowly after we've built muscle is because the bigger the calorie deficit, the greater the proportion of tissue loss that comes from muscle.

This means if we lose slowly, we ultimately lose less muscle (study, study, study). 

Specifically, we want to reach for a weekly body weight loss of 0.7% (study). If you weigh 150lbs (68kg), that’s 1 pound (0.45kg) per week that you can safely lose.

Here are the rules for how to lose weight while building muscle:

Bonus video


Calorie targets for losing weight

Here's how to determine how many calories are required to lose weight:

You don't have to do anything else. It's not complex. It requires discipline.

What about when I cheat?

If you have an off-day where you overeat considerably, that's okay. It will happen. Be accepting of it instead of getting so anxious that you throw in the towel and binge for a few days until you eventually fall off the diet.

Whenever you deviate from the diet, be calm, put it behind you, and get immediately back to eating and exercising properly the next morning. Don't regularly give yourself prolonged "grace periods." That's a slippery slope.

If you find yourself frequently cheating, then put in the work to always have pre-made snacks and meals that you'll depend on when you don't have the energy or time to cook something or are feeling the urge to eat out. Prepare them in advance and have them on-hand at home, work, and wherever else you eat.

You can also find affordable, pre-made meals at your local supermarket. Just read the nutrition labels carefully.