How to Increase Muscle Mass as a Hardgainer

The Basics of Weight Gain

Fundamentally, any change in body composition (e.g. fat loss and muscle gain) is controlled by your daily caloric intake.

  • If you consume more calories than you expend daily, your bodyweight will increase.
    • This scenario is called a positive energy balance. This is where muscle gain occurs.
  • If you consume fewer calories than you expend daily, your bodyweight will decrease.
    • This scenario is called a negative energy balance. This is where fat loss occurs.
  • If you consume the exact amount of calories that you expend daily, your bodyweight will not change.
    • This scenario is called a neutral energy balance.

Generally speaking, gaining weight in the form of muscle requires the simultaneous existence of 2 factors:

  1. Engaging in a strength training program
  2. Consuming more calories than you expend daily. To find out how to calculate your daily energy expenditure, check out this article.

For many hardgainers, factor #1 does not pose much of a challenge. Training in the gym for 1 hour, 3-4 times per week, can be relatively easy compared to eating enough calories every day to elicit consistent weight gain.

What is a Hardgainer?

The aptly-named hardgainer is an individual who has a hard time gaining weight (muscle or fat).

Typical Characteristics of a Hardgainer:

  • Relatively high metabolic rate
    • Hardgainers burn more calories per day compared to most individuals
  • Can be male or female
    • However, hardgainers are more likely to be male, because men generally have a significantly higher metabolic rate than women
  • Relatively low percentage of type II muscle fibers (fast twitch) compared to type I (slow twitch). Type II fibers have a greater diameter than type I fibers. Therefore, hardgainers tend to have smaller muscles.
  • Bone structure tends to be relatively narrow (e.g. smaller waist, wrists, and ankles)

Why do Hardgainers have a Hard Time Gaining Muscle?

As previously stated, eating enough calories to elicit muscle gain is often challenging for hardgainers. This is primarily due to the hardgainers’ high metabolic rate.

Here’s an example:

  • There are two individuals of equal body type (i.e. equivalent limb proportions, height, weight, etc.), but they differ physiologically, and consequentially have different metabolic rates.
  • Individual “A” must consume 2000 calories per day to maintain bodyweight.
  • Individual “B” must consume 3500 calories per day to maintain bodyweight.
  • B is the hardgainer.
  • In order to maintain weight, B must consume 75% more calories than A.
  • If A and B eat the same type of food, B will have to eat almost double the volume of food that A eats.
  • In order to gain muscle mass, B must eat significantly more calories per day compared to A. As a result, B will have a harder time putting on muscle.

The Non-Negotiables

Metabolic rate, capacity for muscle gain, and morphology (i.e. frame size & shape and limb proportions) are primarily determined by genetics, rendering them unchangeable (at least with today’s technology).

Organ size can vary with body size [1]. Larger people tend to have larger organs. This presents an additional challenge for hardgainers as they tend to have an overall smaller frame, potentially limiting their stomach capacity, and therefore limiting their ability to consume large quantities of food relative to larger framed individuals.

How much time should the hardgainer spend thinking about genetic limitations? ...none! Hardgainers will succeed in putting on muscle by focusing on what they can change instead of what they can’t.

The Hardgainers Solution

Eat more. Eat more. Eat more. There is no better solution (remember, muscle gain is fundamentally controlled by caloric intake). Hardgainers often underestimate how much food they need to consume in order to gain muscle. If you think you are eating enough to gain muscle, but aren’t gaining muscle…you aren’t eating enough! It’s that simple, but simple things aren’t necessarily easy. Unfortunately, force-feeding is often a tactic that the hardgainer will need to employ in order to gain muscle mass.

Optimal Foods for Hardgainers

In order to force-feed as little as possible, hardgainers must include calorie-dense foods in their diet. Calorie density = the amount of calories per unit of food weight or volume. Calorie-dense foods are high in calories relative to their mass and volume, so eating them will have you consuming greater amounts of calories while feeling less full. Peanut butter is an example of a calorie-dense food (166 calories per ounce). Conversely, 0% fat Greek yogurt is an example of a food that is not calorie-dense (17 calories per ounce).

Since hardgainers will need to consume a greater amount of calories than most people, they will benefit from buying inexpensive foods to limit the grocery bill. The following is a list of calorie-dense foods that are typically inexpensive, or have inexpensive options.

  • Peanut Butter (166 calories per ounce) [2]
  • Olive Oil (243 calories per fluid ounce) [3]
    • Compare to a low calorie salad dressing (33 calories per ounce) [4]
  • Whole Milk (150 calories per cup) [5]
    • Compare to skim milk (90 calories per cup) [6]
  • Whey Protein Powder (123 calories per ounce) [7]
  • Ground Beef, Cooked, 80% Lean (77 calories per ounce) [8]
    • Compare to 95% lean ground beef (55 calories per ounce) [9], also higher fat concentration beef tends to be cheaper than leaner options
  • Old Fashioned Oats, Dry (106 calories per ounce) [10]
  • Cream of Rice, Dry (105 calories per ounce) [11]
  • Bananas (25 calories per ounce) [12] (Bananas are calorie-dense relative to many other fruits, and very inexpensive)
    • Compare to less calorie-dense fruit, such as:
      • Strawberries (10 calories per ounce) [13]
      • Blueberries (15 calories per ounce) [14]
      • Apples (15 calories per ounce) [15]
  • Pasta, Dry (105 calories per ounce) [16]
  • Brown Rice, Dry (105 calories per ounce) [17]
  • Chicken Thighs, With Skin, Cooked (70 calories per ounce) [18]
    • Compare to the more expensive and less calorie-dense skinless chicken breast (47 calories per ounce) [19]
  • Cheddar Cheese (114 calories per ounce) [20]

The above list is not meant to be a comprehensive resource for calorie-dense foods; rather, it is meant to help you get some ideas of what you can add to your current diet if you’re a hardgainer.

General Tips

  • Consider Using a Food Scale

    • Using a scale to measure your food will help you more accurately determine your daily caloric intake.
    • Measuring your food often isn’t necessary for gaining weight, but if you find that your attempts to put on muscle aren’t working, using a scale will help ensure that you reach your calorie goal. Remember, gaining weight is simply a number game; it’s all about achieving a positive energy balance with your daily caloric intake.
  • Limit Fiber

    • Fiber should be an essential part of your diet, but make sure that you do not consume it in excess. Fiber is a zero-calorie nutrient that contributes to the sensation of fullness; eating it in large amounts will have you feeling full while limiting caloric intake (both are counterproductive if your goal is to gain muscle).
    • Don’t completely remove fiber from your diet, but pay attention to nutrition labels so that you can avoid eating large amounts of high-fiber foods.
    • To learn more about fiber and how it interacts with the body, check out this article.
  • Drink your Calories

    • Consuming calorie-dense drinks will help boost your caloric intake without contributing much to the sensation of fullness.
    • Drinking a couple shakes per day, in addition to what you already eat, will help you gain muscle.
    • A single shake made with 1 cup of whole milk, 1 oz of whey protein, and 1 oz of peanut butter = ~450 calories. If you drink two of these shakes per day, you will increase your daily caloric intake by nearly 1000 calories.
    • A shake, like the one described above, is essentially an additional meal because it contains a significant amount of calories, carbohydrate, protein, and fat. Limit your intake of pure sugar beverages like soda and juice, as they don’t offer well-rounded nutrition.  
  • Don’t be Afraid to Indulge

    • Fat gain doesn’t just happen overnight, especially for hardgainers. Junk food is both non-filling and calorie-dense. In a pinch, take advantage of less healthy options to help you reach your daily caloric goal, but don’t make it a long-term habit.
  • Take Advantage of Whey Protein

    • Don’t think of whey protein as a supplement; think of it as food. Whey contains a significant amount of calories, unlike zero-calorie supplements like creatine, caffeine, and multivitamins. Pound for pound, whey protein is actually significantly more calorie-and-protein-dense than 80% lean ground beef (123 calories/oz compared to 77 calories/oz, respectively).
    • Including whey protein in your diet can help ensure that you reach your calorie and protein requirements for the day; you can easily add it to shakes, water, and oatmeal.
  • Buy in Bulk

    • Once you find calorie-dense foods that you enjoy, it is best to start buying them in bulk so that you can save money.
    • Buying in bulk also helps save you time because you will take fewer trips to the grocery store.
  • Cook in Bulk

    • To be able to eat the necessary amount of food to gain weight, you will need to have meals readily available throughout the day. For this reason, it’s best to prepare your food in large quantities. When you eat to gain muscle mass, you go through food much more quickly.

Preparing your food in bulk will also help you save time because you will spend less time cooking.

Easy Meal Ideas for Hardgainers (Sample Day of Eating)

Meal #1:

  • ½ cup of dry oats: 150 calories
    • Protein: 5 g
    • Carb: 27 g
    • Fat: 3 g
  • 2 ounces of peanut butter: 333 calories
    • Protein: 14 g
    • Carb: 11 g
    • Fat: 28.5 g
  • 1 ounce of whey protein: 123 calories
    • Protein: 21.5 g
    • Carb: 3 g
    • Fat: 2.5 g
  • 1 large banana: 121 calories
    • Protein: 1.5 g
    • Carb: 31 g
    • Fat: 0.5 g
  • 1 cup of whole milk: 150 calories
    • Protein: 8 g
    • Carb: 12 g
    • Fat: 8 g

Total Protein: 50 g
Total Carb: 84 g
Total Fat: 42.5
Total Calories: 877

Meal #2:

  • 5 ounces of chicken thighs, with skin, cooked: 350 calories
    • Protein: 35.5 g
    • Carb: 0 g
    • Fat: 22 g
  • 2 ounces of cheddar cheese: 228 calories
    • Protein: 14 g
    • Carb: 1 g
    • Fat: 9 g
  • 3 ounces of dry brown rice (to be cooked, of course!): 315 calories
    • Protein: 7 g
    • Carb: 65.5 g
    • Fat: 2.5 g
  • 0.5 ounces of olive oil: 122 calories
    • Protein: 0 g
    • Carb: 0 g
    • Fat: 14 g
  • Serving of vegetables: ~0 calories
    • Negligible macronutrients

Total Protein: 56.5 g
Total Carb: 66.5 g
Total Fat: 33.5 g
Total Calories: 1015

Meal #3:

  • 3 ounces of dry pasta (to be cooked, of course!): 315 calories
    • Protein: 11 g
    • Carb: 63.5 g
    • Fat: 1.5 g
  • 4 ounces of 80% lean ground beef: 308 calories
    • Protein: 30.5 g
    • Carb: 0 g
    • Fat: 19.5 g
  • 1 ounce of olive oil: 243 calories
    • Protein: 0 g
    • Carb: 0 g
    • Fat: 28.5 g
  • Add sauce and seasoning for flavor: variable
  • Serving of vegetables: ~0 calories
    • Negligible macronutrients

Total Protein: 41.5 g
Total Carb: 63.5 g
Total Fat: 49.5 g
Total Calories: 866 (at least)

Meal #4:

  • 1.5 ounces of whey protein powder: 184 calories
    • Protein: 32.5 g
    • Carb: 4.5 g
    • Fat: 3.5
  • 1.5 cups of whole milk: 225 calories
    • Protein: 12 g
    • Carb: 18 g
    • Fat: 12 g
  • 1.5 ounces of peanut butter: 250 calories
    • Protein: 10.5 g
    • Carb: 8.5 g
    • Fat: 21.5 g
  • 6 ounces of banana: 150 calories
    • Protein: 2 g
    • Carb: 39 g
    • Fat: 0.5 g

Total Protein: 57 g
Total Carb: 70 g
Total Fat: 37.5 g
Total Calories: 809

Total Daily Nutrients:

Protein: 205 g
Carb: 284 g
Fat: 163 g
Total Calories: 3567

The list of sample meals above is only a sample, it is not meant to be a comprehensive diet plan. Be sure to eat a few servings of vegetables daily!

My Own Experience

Before I started lifting weights and eating to gain muscle I was 6’ and 135 lbs. After two years of disciplined training and eating, I weighed 195 lbs. The rate of weight gain over those 2 years averaged out to be about 2.5 lbs per month, which is a little over half a pound per week. Most of the weight gained was muscle mass, with a small percentage of it being fat tissue. When I started the process of gaining muscle, I was genuinely surprised at the amount of food that I had to eat every day in order to gain weight. I force-fed a lot, and there were many days where I never experienced hunger in any capacity (which is a fortunate problem to have).

The more muscle I gained, the more I had to eat to continue gaining muscle. When you add muscle mass to your frame, your daily metabolic rate (i.e. the amount of calories that you burn in a day) increases because a larger physique requires more energy to maintain. To get from 190 to 195 lbs, I had to eat about 4500 calories per day. The heaviest I’ve ever been was about 210 lbs, and to get to that point I had to eat about 5000 calories per day for many months. In my experience, diet is the most challenging aspect of strength training. Going to the gym has never been much of a problem, but having a regimented diet requires consistent effort and planning throughout the day, every day.

When I ate to gain muscle mass, I ate a lot of everything: protein, fat, and carbs. I ate plenty of saturated fat and simple carbs. Despite all of this, my routine lipid and glucose tests always came back with excellent results. This doesn’t mean that everyone who eats a high-calorie diet with relatively large proportions of saturated fats and simple carbs won’t experience adverse health effects, as the individual response to such a diet can vary significantly. If you are young, have an active lifestyle, and are adding significant amounts of lean muscle tissue to your frame, your chances of experiencing adverse health effects are lower. The best way to know if your diet is affecting your health is to get blood work from a doctor. Keep in mind that you won’t be on a weight gain diet forever.

Benefits of Being a Hardgainer

The “problem” of being a hardgainer can actually be beneficial, depending on your perspective.

Hardgainer Benefits:

  • Hardgainers tend to be relatively lean, and need to worry less about gaining too much fat. Therefore, they can enjoy food more liberally.
  • Hardgainers, once they find the right balance of diet and training, are likely to have an excellent strength-to-bodyweight ratio due to their slender frames and leanness.
  • Having a relatively high percentage of type I muscle fibers means that hardgainers have a physiological advantage for endurance activities.


Here are the big takeaway points:

  • To gain muscle mass, hardgainers must consume more calories than they expend daily.
  • Hardgainers have a difficult time gaining muscle mass because they have a high daily energy expenditure (i.e. metabolic rate) that is genetically determined. 
  • To overcome a high metabolic rate, hardgainers must eat a large amount of calories every day.
  • To facilitate a high calorie diet, hardgainers should consume primarily calorie-dense foods.
  • To see appreciable gains in muscle mass, hardgainers must put in a consistent daily effort with their diet.
  • Force-feeding is often necessary for hardgainers to gain muscle.


1.) Korneliussen, I. (2015, April 17th). How different are we on the inside? Retrieved from

2.) Nutrition of peanut butter:

3.) Nutrition of olive oil:

4.) Nutrition of light salad dressing:

5.) Nutrition of whole milk:

6.) Nutrition of skim milk:

7.) Nutrition of whey protein powder:

8.) Nutrition of 80% lean ground beef (cooked):

9.) Nutrition of 95% lean ground beef (cooked):

10.) Nutrition of old fashioned oats (dry):

11.) Nutrition of cream of rice (dry):

12.) Nutrition of bananas:

13.) Nutrition of strawberries:

14.)  Nutrition of blueberries:

15.) Nutrition of apples:

16.) Nutrition of pasta (dry):

17.) Nutrition of brown rice (dry):

18.) Nutrition of chicken thighs (cooked, with skin):

19.) Nutrition of chicken breast (cooked, without skin):

20.) Nutrition of cheddar cheese: