While some of us are experts at gaining weight unintentionally, how do we go about putting on healthy weight in the right way? Weight gain sounds easy, but it actually requires a strategic approach to nutrition and training to get it right. And just like weight loss, muscle gain must start with getting the right amount of calories each day.
Here is everything you need to figure out exactly how much you should be eating each day to put on more muscle.
Calculate Your Calorie Needs for Weight Gain
Use this simple calculator to find out exactly how many calories you need a day to start gaining healthy weight.
How to Gain Weight
Weight gain is primarily driven by eating more calories than your body burns on a consistent basis.
But it takes energy to store energy. In other words, your body burns calories digesting food and storing this food as either body fat or muscle. In contrast, losing stored body fat/muscle releases energy for use. This is why excess calories are needed to gain weight and cutting calories is an effective approach to losing weight.
With any weight gain, the goal is typically to increase lean mass while limiting gains in body fat. This is because muscle provides numerous health benefits, whereas excess fat is really just energy reserves, and high amounts of body fat are associated with less desirable health outcomes.
Fat vs. Muscle Weight
Muscle is what helps keep us strong and healthy as we age. It is closely linked to recovery from injury and illness, and may even play a role in preventing obesity and diabetes. Moreover, strength training has been linked to stronger bones (1,2).
These positive effects are partly due to the fact that muscle is more metabolic than fat. One pound of muscle burns 4.5 to 7 calories per day, whereas one pound of fat may only burn a couple of calories. Your lean tissue makes up approximately 10 to 20% of your total daily calorie needs compared to only 4 to 5% for body fat (3,4,5).
In addition, muscle also serves as a storage place for key nutrients - like glycogen (aka carbs), water and amino acids. Thus, having more lean tissue means you process and store your calories more efficiently, and that your higher weight and output allows you to eat more calories in general.
For many, adding muscle means you can eat more food and look more fit - a highly desirable result. More lean muscle mass can also make it easier to maintain fat loss.
So how can you ensure you gain more muscle than fat? Ultimately it comes down to nutrition and training.
How Many Calories in One Pound of Fat?
Storing dietary fat as body fat requires little energy - so one gram of stored fat provides about nine calories per gram (similar to what 1g of fat eaten supplies) or 4,000 calories per pound.
Carbs and protein, on the other hand, require a little more energy to be stored as body fat - nine calories consumed results in only 7.35 calories stored, or 3,300 calories per pound. The average of these two is where the understanding that it takes burning or cutting about 3,500 calories to lose one pound of fat comes from (6).
How Many Calories in One Pound of Muscle?
It takes even more energy to build and store muscle mass through muscle protein synthesis (MPS). An estimated 2,500 to 2,800 excess calories is needed to gain one pound of lean mass. Of course, this number is highly dependent on individual factors like level of training, starting body composition, genetics and overall diet.
What Weighs More, Muscle or Fat?
Because fat supplies more energy per gram than muscle and takes up more space, some may interpret this as fat weighs more than muscle. And because muscle is denser - one pound of muscle takes up 18% less space than fat, some would argue the opposite. But either notion would defy the laws of physics since one pound of anything still weighs a pound.
Gaining muscle will not make you weigh less, but it may make you look and feel leaner overall. Muscle growth often means your weight will increase - which is why MPS requires excess calories, even if you end up looking smaller and more dense in the process.
At higher levels of body fat, your body can be in a calorie deficit and still build muscle, as long as strength training and higher protein intake is incorporated (7). This is because your body will use fat stores to fuel itself. Of course, this is difficult to achieve and can take longer than focusing on muscle gain or fat loss alone. It is also not an ideal approach for everyone.
How to Calculate Lean Body Mass
Body composition is a key element of gaining muscle mass. Your starting body fat percentage can affect how much muscle you can gain overall, how lean and shredded you look at the end, and the type of bulking diet that works best for you.
Understanding how to calculate your percent body fat is also important for figuring out how much muscle mass you've actually gained, compared to fat.
You can calculate your body composition a number of different ways, some are more accurate than others. Regardless of which method you choose, you should measure your progress using the same approach.
At home scales and handheld, readers are quick and inexpensive and don't require the assistance of an expert, but tend to have a higher margin of error.
For a more accurate approach, numerous companies offer more accurate measurements, like underwater weighing and DXA scans, through appointments. These can be slightly more costly, but are significantly more accurate and provide more detailed readings. DXA scans can even show you where you store muscle and fat in your body in great detail.
Determining Your Weight Gain Calorie Needs
The exact amount of calories you need consume each day to gain muscle mass are most strongly dependent on your level of training and starting body composition. While it takes 2,500 to 2,800 additional calories to build one pound of muscle, this doesn't necessarily mean increasing your intake by this much is automatically going to result in healthy gains.
Use this online calculator or the simple steps below to calculate your exact calorie needs for muscle gain.
Step 1: Determine Your Maintenance Calories
Use an online calculator or quickly estimate with these two steps:
1. multiply your current weight by one of the following
- Women = weight in lbs. x 10
- Men = weight in lbs. x 11
2. Add in exercise and daily activity by multiplying by one of the following
- 1 - Little to no exercise.
- 1.1 - Light exercise or training 1 to 3 days per week.
- 1.2 - Moderate exercise 2 or more days per week.
- 1.4 - Hard exercise 3 or more days per week.
- 1.6 - Working out 2 or more times a day.
Step 2: Add Your Calorie Surplus
For many, increasing your daily calories by 5 to 10% is sufficient in promoting lean muscle growth. For example, if your daily calorie needs are 2500, you can consume 250 extra calories per day.
But there may be some differences in calorie needs per person based on starting body composition and level of training.
The less trained you are, the more quickly you can gain muscle mass (8). This is because you have not yet started to tap into your full muscle building potential and may find it easier to build a larger amount of lean mass more quickly than a highly trained individual who has already built a large amount of muscle.
Moreover, some research suggests that naturally lean individuals with a low body fat percentage are more likely to gain muscle than body fat in a large calorie surplus (9,10,11,12,13). In addition, naturally skinny individuals may require more calories overall - sometimes requiring them to eat to the point of discomfort on a regular basis.
In contrast, a higher body fat percentage may promote more fat gain. If you have a higher body fat percentage to begin with, it might be worth considering a cut instead of trying to bulk - especially if you are already highly trained.
If you are less trained, you may have more success putting on lean mass in a surplus, but could also find that you are able to lose fat and gain muscle at the same time.
You can use the following research-based recommendations to determine more specific calorie goals:
|Lean, Untrained||Add +300 to 1,000 calories|
|Lean, Trained||Add +100 to 300 calories|
|Higher Body Fat %, Untrained||Consider cutting 15% to 20% of your calories and eat at least 1g of protein/pound body weight|
|Higher Body Fat %, Trained||Consider cutting 15% of your calories and eat at least 1.2g of protein/pound body weight|
- Lean - less than 10% body fat for men and less than 20% for women
- Higher Body Fat % - more than 15% body fat for men and more than 25% body fat for women
- Untrained - less than one year of weight training/muscle building experience
- Trained - 2 or more years of weight training/muscle building experience
Step 3: Calculate Your Macros
Once you have a rough estimate of how many calories you need to eat a day to gain weight, you can find your optimal macro ratios to promote more lean mass. Use the following guidelines to get started:
- 1 to 1.5 grams of protein per pound of body weight (eat more protein in you are looking to cut fat or have more muscle mass, to begin with).
- For example, a 200-pound adult would need 200 to 300 grams of protein per day on a bulking diet.
Tip: you can also estimate your protein needs based on your percent lean mass. You need about 1 gram of protein for every pound of lean mass, and should never go below this amount when looking to bulk.
- 30% of calories from fat.
- For example, if you need 2750 calories per day to bulk, 30% of these calories should come from fat.
- (2750 x 0.30)/ 9 calories per gram = 92 grams of fat per day
- For example, if you need 2750 calories per day to bulk, 30% of these calories should come from fat.
- Remaining calories from carbs.
- Calculate your remaining calories by subtracting calories from protein and fat. Then divide by four to get your grams of carbs per day.
Get the most out of your macros with the best muscle building foods - lean proteins, nutrient-dense plants, and healthy fats.
How to Gain Muscle Fast
The rate at which you can gain muscle depends on how much muscle you've already gained and how effectively you are applying the right nutrition and training aspects. Beginners can expect to gain muscle much faster, sometimes as much as 1 to 1.5% body weight per week. Compared to advanced lifters who may only gain a pound or two of muscle each year.
There is no secret to speed up this process since most people have genetic limits to how much mass they can build effectively. And increasing calories too much too quickly can result in more body fat gain than muscle.
Get your daily calorie needs down to a science and start building more lean mass now with this free meal prep toolkit for muscle gain.