Nutrition for gaining muscle without fat

Gain muscle mass fast

Fork with measuring tape wrapped around it like pasta


1. Overview

2. Eating BIG for BIG gains?

3. 2 critical nutrition components

4. What is your metabolic range?

5. Finding your metabolic range

6. Edges of your metabolic range

7. Learnings

5. References

The gist

  1. A research study that tested the effects of adding 500 calories to the diets of those on a resistance training program found that the extra calories added fat, not muscle.

  2. To gain muscle you need enough protein and enough calories. Excess calories to the point of fat gain will not speed up this process and neither will excess protein.

  3. To maximize rates of muscle growth, you want to find the high end of your metabolic range.

  4. Follow the provided step-by-step process which includes watching your weight, body composition and/or strength, and continually adding small amounts to your daily intake to find this point.

  5. Those described as “hard-gainers” (e.g. those in their early 20’s, teens, and those with active jobs) will have a much larger metabolic range than others.

You gotta eat BIG for BIG gains... right?

You want to build more muscle and may have heard that the fastest way to do this is to “bulk” by eating BIG. Do you really need that additional body fat from bulking in order to gain muscle quickly? Is it necessary to eat all those extra calories?

Let’s check out this research study by Garthe and colleagues at The Norwegian School of Sports Science in Oslo, Norway [1]:

The study divided participants into two exercise groups:

  1. Resistance training and adding 500 extra calories on top of a maintenance diet

  2. Resistance training and no addition to diet

The results: Gains in lean body mass did not vary between groups. However, fat mass increased more in the +500 calories group.

In other words, they concluded that all the extra calories added was extra fat.


Here is a table from the study:

You can see that there is no statistical difference in LBM (Lean Body Mass) in the NCG (+500 calories) group, but a massive gain in fat mass.

What if there was a way to get that extra bit of increased rate of muscle gain without the added fat?

The 2 critical nutrition components for gaining muscle


Protein synthesis or, in other words, muscle growth is dependent on dietary protein and resistance training.

The key is enough to maximize rates of muscle growth. Remember, your body can only use so much protein (i.e. 0.3 g/kg) and can only add so much muscle at one time (i.e. every 3-5 hours). Therefore, more protein after this point does not equal more gains.

For more on this see our resource Protein for gaining muscle: there’s more to it than just hitting a daily target


Your body’s gas tank. Energy must be provided to fuel workouts, the protein synthesis process and to actually be incorporated into muscle tissue (i.e. the protein calories).

You want to be at the high end of your metabolic range while maintaining body fat levels so energy is easily available for both muscle growth and high performance in the gym.

What is your metabolic range? And where should you be in this range?

All of us have a range of calories where we can maintain body fat levels and some people's range is much larger than others [5].

For example, Suzy Q. does not gain weight if she eats over 1743.42 calories per day or lose weight if she eats under it. This is because a person’s calories for weight maintenance are not at a set point that is this refined. Instead, it is more likely that if she eats within a certain range (e.g. 1600-1900) she will not gain or lose fat.

For muscle gain without fat gain, what we are looking for is the high end of your range.

In Suzy’s case, she should be aiming for closer to 1900 calories to maximize the amount of energy her body has for great workout performance and building muscle without gaining fat. This is where the additional burn between 1600 and 1900 will go: increased muscle generation, increased workout performance, increased subconscious activity away from the gym and, for some, possibly a small increase resting metabolic rate.

We can use the analogy of your body as a race car: If the driver has the premiums and extra cash they are going to be less conservative on the gas pedal and will also spend more on the upgrades under the hood. So if your body has the extra energy, it can afford to expend more fuel on movement, performance, and on upgrading its muscles!

Therefore, you may need to increase your intake but only to the point where you are not gaining significant amounts of fat. You can figure this out by continually and slowly increasing the number of calories you consume while watching the important metrics discussed below.

Finding your metabolic range

If you want more tangible numbers, Eric Helms, natural bodybuilding coach for 3DMJ, PhD in Exercise Physiology, and professor at Auckland University, estimates:

  • Beginners can expect to gain 1 to 1.5% body weight per month

  • Intermediates, 0.5 to 1% per month

  • And advanced, 0.5% or less per month



  1. For a 180 lb male that’s 2-3 lbs/month for the first 4-8 months and less than 1 lbs per month after 3 to 5 years of consistent training.

  2. For a 130 lbs female it would be 1-2 lbs/month as a beginner and less than 0.7 lbs per month as an advanced lifter.


To maximize gains, avoid the deficit and avoid going overboard

Being in an energy deficit (weight loss) drastically blunts the rates at which muscle growth can occur [2]. Knowing there isn’t as many calories available, your body doesn’t want to spend much on the energy expensive process of building muscle.

However, being in a caloric surplus beyond the increase needed to fuel the muscle building process and high performance has no effect on increasing rates. Therefore, more calories after this point does not equal more gains, except in fat.

Can you lose fat AND build muscle?

While fat can be very easily stored at almost no metabolic cost, this is not true for muscle mass. Muscle mass is much more metabolically costly to synthesize than body fat. In other words, it’s a lot more work for your body to build and maintain muscle than fat.

Overweight individuals can lose more body fat and keep more muscle because there is more fat to mobilize [3]. For those new to resistance training, muscle growth occurs much more quickly so the effect of gaining muscle while losing fat will be more pronounced [4].

Therefore, the more overweight the person is and the less experience they have resistance training (i.e. further they are away from their genetic potential for muscle mass), the more capable they will be of gaining muscle and losing fat at the same time. Keep this in mind if this is your situation. The weight on the scale may not move, but look for improvements in the gym, the mirror and the way your clothes fit!

I’m a “hard-gainer”, why am I not gaining muscle?

Individuals, commonly those in their early 20’s and teens, could find themselves adding and adding and adding calories with no gains in muscle, strength or weight. If you’re one of these individuals, you may indeed find yourself eating BIG.

The process of building muscle increases caloric expenditure and this along with increases in NEAT (subconscious everyday physical activity away from the gym, such as walking and fidgeting) contributes to this “hard-gainer” phenomenon. Essentially, you eat more and your body will find more ways to use this energy. This is the main reason why weight gain is much less than expected after a caloric increase [5,6].

This may also be the case for those who have active jobs. You would be surprised by how many extra calories your body will burn in your daily activities if it has them available.