Lose Weight
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This is page five of a How to Build Muscle guide. Begin here.

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The science of losing weight quickly

This page summarizes the research on how to lose fat while also building muscle. (Yup, I'll share tips on how to lose weight, but it honestly mostly boils down to self-control.)

Whether losing fat before or after building muscle, this page is your master reference.

Why you fail to lose weight

Although I’m sharing straightforward and effective 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 didn't get fat because of a “slow metabolism” (unless you have hypothyroidism). In fact, genetics only play a small part in a propensity for obesity. And the predisposition is actually 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, some overweight people do have the self-control when it comes to eating to lose weight, but they lack the diligence to lose the weight quickly and consistently. Typically because they don't realize how many calories they're eating. 

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.

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

But, when this happens to fit people, the difference is that they say "no" more often. They don't cave in 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.

(If you’re suffering from anxiety that triggers compulsive eating, you'll need to talk to a therapist. Crack open Yelp and find someone.)

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 personalized needs.

On a chemical level, most people are completely 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 the most efficient muscle building plan for both men and women.

← Start with part one

When to lose weight

When you are confident you have the will and self-control to adhere to a fat loss diet, you must decide whether to lose the fat before you start this program or afterward. 

Never try to lose a lot of fat while on a muscle building program because it will conflict with your calorie requirements for muscle gains, and it will make arm muscle measurements invalid because your arms will be simultaneously shrinking from lost fat.

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. The less fat you have, the more your muscles show. This keeps you motivated. 

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:

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If you only have a bit of fat and you’re not in an immediate rush to lose it, lose the fat 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 program due to the strict calorie requirements (unless you’re physically active), so you might as well lose all the fat at once.

The before and after approaches to weight loss differ significantly. The before, which isn’t focused on retaining muscle mass, is quickly accomplished by running a daily calorie deficit. 

Losing weight after this program entails eating your normal amount of calories (but never more) and doing an intense burst of cardio on your non-workout days so you create a calorie deficit through exercise instead of under-eating. 

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 lose motivation.

Pre-muscle weight loss plan

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

One 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 how to lose weight tips:

Here’s the recap. Follow this religiously if you want to lose weight fast:

The methodology comes down to this: When accomplishing your goals, don't belittle the low-hanging fruit. Go for them. Then, reach a bit higher. Keep incrementing.

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 fast. To do this, we must 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. 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 in the nutrition section of this guide. Go check it out if you haven't.)

Before we move on, 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:

Bonus video

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Post-muscle weight loss plan

Yes, it's possible to burn fat while building muscle. But it's not the weightlifting itself that burns the fat. It's consistent cardio and dieting.

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

The reason we lose fat slowly once we have muscle is because the bigger the calorie deficit, the greater the proportion of tissue loss that comes from muscle. This means if we lose weight 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

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How many calories to lose weight

Here's how to determine how many calories you require to lose weight:

Yup, it's that simple. You don't have to do anything else.

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 restart the diet. This start-and-stop approach doesn't work in the long-term. It will endlessly repeat itself. Repeat itself.

So whenever you deviate from the diet, be calm, put it behind you, and go right back to eating and exercising properly the next morning. We're only human.

If you find yourself frequently cheating, then you'll have to put in the work to always have "if then food" on-hand. These are pre-made snacks and meals that you'll rely on when you don't have the energy or time to cook something fresh. Prepare them in your down time and always have them on-hand at home, work, and wherever else you eat.

If you can find affordable pre-made meals at your local supermarket — and if the meals are low in carbs (e.g. less than 35% of the total calories) — feel free to eat them instead of making your own meals.

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

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