How Does Protein Build Muscle? [and Lose Fat]

Protein contains essential amino acids your body uses to build muscle. However, where you get your protein, when you eat it, and your training plan all play important roles in turning your workouts into muscle-building results.

Ask anyone about weightlifting and they’ll say you need protein—lots of it. But why? What you really want to know is how to build muscle, and even better, how to build muscle fast. Protein makes that all possible. Let’s first find out how protein works.

Why Does Protein Make you Gain Muscle?

There’s a tendency to focus on time in the gym when creating your fitness plan. The fact is, diet is at least as important as your workout routine. And protein is the cornerstone of any lifter’s nutrition plan. Here’s why.

Protein is the Building Block of Muscles

Your muscles are made primarily of protein structures called filaments. The two predominant filaments found in muscles are actin and myosin. These filaments are built out of amino acids that are found in protein, not other foods.

The reason why your body needs protein is that it takes the amino acids found in the protein you eat, breaks it down, and restructures it into actin and myosin. Your body literally turns protein into muscle tissue.

What Happens if you Lift Weights but Don’t Eat Enough Protein?

The reason protein is necessary to build muscle is that other foods (carbohydrates, fats, vitamins, minerals) do not include the amino acids that serve as the building blocks of muscle tissue.

It’s important to get enough protein for muscle gain. If your muscles are put through stress (like a good workout) but aren’t provided with enough protein then they’ll struggle to repair themselves. This will increase your recovery time and inhibit your ability to grow larger, stronger muscles.

How much Protein do you Need to Build Muscle?

You’ll see a wide variety of answers to this question. This is because the amount of protein for someone with a sedentary lifestyle is much lower than what’s required for weightlifters and other athletes.

You’ll need to get yourself on a high protein diet plan for muscle gain, while still balancing your nutrition plan to make sure you are getting all the other macro and micronutrients you need.

Protein Needs are Based on Lifestyle

For a person living a sedentary lifestyle, the body requires only about .36 grams of protein per pound of body weight each day.

The amount of daily protein the body requires is drastically different for athletes and weightlifters. This study suggests that the optimal protein intake for muscle gain is about .8 grams of protein per pound of body weight. It’s important to note the statement, “regular exercise increases daily protein requirements…by perhaps as much as 100% vs. recommendations for sedentary individuals.”

You can see there’s a big difference here. And you’ve probably heard the maxim that if you want to use protein to build muscle you should be eating 1 gram of protein for every pound of body weight (2.2 grams per kilogram).

Protein Calculation for Weightlifters

For beginners and for those on a strength training program, .8–1 grams of protein for each pound of body weight per day is a great benchmark. For those on a cutting program, where the goal is to lose fat without sacrificing muscle, you’ll want to increase your protein intake. 1.2 grams of protein per day is a good target in this case.

So, an individual weighing 175 pounds should be eating between 140 and 210 grams of protein per day, depending on frequency, intensity, and type of workout plan.

Where you get your Protein Matters

Remember those amino acids that your body uses to build muscle? Well, it’s important to note that different protein sources contain different amino acids. When you choose your high-protein foods keep the following in mind:

  • Get protein from a variety of sources to obtain different amino acids.
  • Choose protein sources that metabolize at a high rate to maximize your protein usage.

Net Protein Utilization

That’s right, not all protein is exactly what it seems. Some proteins metabolize more quickly than others, and some can be absorbed by your body more easily. The ease of protein metabolization is calculated as Net Protein Utilization—the higher the better. Here are a few options (including vegetarian and vegan options) that offer great protein profiles.

  • Beef – 7 grams of protein per ounce – 73% Net Protein Utilization
  • Eggs – 6 grams of protein per egg – 94% Net Protein Utilization
  • Salmon – 8 grams of protein per ounce – 81% Net Protein Utilization
  • Chicken – 8 grams of protein per ounce – 80% Net Protein Utilization
  • Whey Protein – 22 grams of protein per ounce – 94% Net Protein Utilization
  • Rice Protein – 22 grams of protein per ounce – 76% Net Protein Utilization
  • Soy Protein – 24 grams of protein per ounce – 61% Net Protein Utilization

Can Too Much Protein Hurt You?

When we consider our daily protein intake for muscle growth we also need to keep in mind the body’s other needs. The question of how much protein is too much comes up often. The answer to this question is very important in order to stay on the path to fitness.

Your Body Will Flush Out Excess Protein

The good news is that you cannot overdose on protein. Unlike some other vitamins or minerals, such as iron, you cannot intake potentially dangerous levels of protein.

Because protein is water-soluble, any protein your body cannot use will be passed out through the urine. If you’re taking in more protein than necessary this can be expensive, since protein-rich foods are usually among the priciest. There are also other reasons too much protein is undesirable.

More Protein Means Less of Everything Else

The real downside of eating too much protein is that you’ll put everything else on the back burner, which can actually cause a massive decrease in muscular gains.

When you eat carbohydrates this causes a slight rise in natural insulin levels which actually make it easier for your body to break down and use protein for muscle growth. Most nutritionists recommend eating carbs and protein together after a workout.

The other downside of a diet with too much protein is that you won’t have room for vitamins and minerals essential for organ health and mental energy. A diet with too much protein and not enough carbs, fats, and micronutrients can leave you feeling lethargic, which decreases the effectiveness of your workouts and inhibits your muscular growth.

Is there an Optimal Time to Take in Protein?

While there is some truth to the idea that having protein right after a workout will provide more results, keep in mind that your body takes times to absorb that protein. Choosing a protein that is metabolized quickly for your post workout meal (like whey protein) is more beneficial than having a slower-acting protein (such as eggs).

But those different protein metabolization rates can be a bonus. Most people think of using protein shakes to build muscle, but the best diet combines several high protein foods for muscle building. This way, your body is breaking down protein for recovery around the clock. A slow-metabolizing protein before bed, such as nut butter or some casein protein, will encourage recovery while you sleep.

The Complete Protein Plan

As you can see from the concepts we’ve discussed, there’s more to maximizing your protein intake to build muscle than just eating lots of it. By planning your diet to balance protein intake with carbs to maximize protein absorption, choosing the best high protein foods, and eating the right protein at the right time you can make the most out of your workouts.

Whether you’re looking to make your first gains or working to break through a plateau in your fitness journey, the lessons here can be instrumental in making a difference.

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