What You Need to Know About Bulking

Man mixing a protein shake with raspberries, protein powder, and milk.
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If you are trying to build muscle but it seems like it's taking forever, your diet may not be sufficient to support the muscle growth you are pursuing. That's because in order to promote muscle protein synthesis, you need an abundance of calories—which are not easy to come by if you are also trying to maintain or lose weight.

Typically, for bulking you need to increase your calories by 10% to 20%. Experts suggest bulking first before cutting.

In some situations, bulking may be the answer. Bodybuilders use bulking techniques to put on as much muscle as possible in their off season. That way, they can make great strides in their physiques quickly.

But before you start eating, it is important to understand how to bulk up properly. You will also need to consider your starting point, your goals, and how much time you have. Here is what you need to know before you get started.

What is Bulking?

Bulking is an effort to gain weight quickly, preferably in the form of muscle, by consuming more calories than your body needs combined with a training program designed to promote muscle accrual.

Typically, when someone wants to bulk up, they will eat as much as they can with regard to the nutritional value of the food. Any and all high-calorie foods are fair game and often consumed in excess to meet daily calorie needs for bulking.

The problem with this approach is that your typical western-style diet is high in carbohydrates, fat, and refined foods, while being low in protein. Studies show that participants who increased their calories by 1,000 per day following a western diet gained weight, but 50% to 67% of the weight they gained was fat.

While the goal of bulking is to gain muscle weight, most people are looking for a jump in muscle mass and not fat. The clean bulk is a more strategic bulking phase prioritizing whole, unprocessed foods that are high in protein, healthy fats, complex carbohydrates, fruits, and vegetables. What's more, a high-protein bulk is more likely to result in greater muscle mass gains and less fat gain.

A 2019 study indicates that anything less than 1.2 grams of protein per kilogram of weight per day will not help you with bulking. In fact, the study suggests you may need 2.2 grams to 3.4 grams of protein per kilogram of weight per day to limit weight gain from fat mass. However, exceeding 2 grams of protein per kilogram of weight per day should not be done without oversight from a medical professional.

Reasons People Consider Bulking

Someone may start bulking for various reasons including:

  • They want to gain muscle and strength for a competition like powerlifting or bodybuilding.
  • They are underweight and would like to gain weight to improve health parameters.
  • They need to meet a specific weight class for a sport.
  • They want to gain muscle for a part in a play or movie.

How Do You Start Bulking?

When you are ready to begin bulking, you will want to first determine how much muscle you want to gain, how many weeks you have to bulk, and what kind of bulk you want to do—clean vs. traditional or "dirty bulk."

Most bulks last anywhere from 6 weeks to 4 months. Some people even claim to be in a bulking phase upwards of a year. However, longer is not always better.

Next, you will want to calculate your daily calorie needs. Start by determining your resting metabolic rate (RMR). This number tells you how many calories you need to do basic tasks and maintain your weight. Once you have that number, add an additional 10% to 20% of calories to add about 0.25% to 0.5% of bodyweight gain per week.

If you're not sure how much you are currently eating, try logging your intake for a week using a food journal app to determine where you're starting from. Tracking your food in an app can also be helpful during your bulk to ensure you are reaching your calorie goals each day.

Nutrition for Bulking

If you're not concerned about gaining body fat while bulking, a traditional bulk will work well for you. A traditional bulk means you eat whatever you'd like to reach your calorie goals. Fast-food value meals and other highly processed foods are fair game. With this style of bulking you may end up with more body fat gain than muscle mass—that's something you will have to decide if it is OK for you or not.

On the other hand, if your goal is to put on muscle with as little body fat as possible, you will want to prioritize the quality of foods and protein. Studies show that when paired with a strength training routine, protein intake should be between 2.2 grams and 3.4 grams per kilogram of body weight to maximize muscle and strength gains during a bulk.

To reach this amount, more than three meals will need to be consumed. Each meal should contain about 0.25 grams of protein per kilogram of weight for young adults and about 4 grams of protein per kilogram of weight per meal for adults.

Eating a variety of whole grains, legumes, fruits, vegetables, nuts, seeds, and lean protein is ideal for putting on lean body mass. The number of meals per day does not matter for gaining weight, as long as the total calorie goals for the day are met.

But bulking diets are often extremely high in calories, making it difficult to meet calorie goals in only two to three meals per day. For that reason, it may be a good idea to spread your calories out throughout the day so you are better able to eat your entire meal without feeling uncomfortable.

Because you have already calculated your calorie needs, you can now determine how much protein you will need each day. To do so, calculate your body weight in kilograms by diving your weight by 2.2. Then multiply that number by 2.2 and 3.4. That is your new range of protein intake per day.

The remaining calories can be split up between complex carbohydrates, fruits, vegetables, and healthy fats. Do not be afraid to use high-calorie foods in your diet including whole milk, ice cream, and cheese. These foods offer nutritional value and can help you reach your daily high-calorie goals.

Fitness for Bulking

Unfortunately ramping up your diet and eating as much as you can is not going to help you put on lean mass unless you combine it with a heavy strength training routine. Studies show that resistance training and daily high protein intake are essential for maximizing muscle-building potential.

More advanced training techniques including super-sets, body part splits, and set-rep schemes can be helpful to break through plateaus and prevent training boredom. Also, incorporating a few sessions per week of high-intensity interval training (HIIT) can be a good strategy for minimizing fat gain. Plus, research suggests that HIIT workouts have a positive effect on muscle gains.

When bulking using resistance training, aim for three to six sets of six to 12 repetitions with a moderate intensity of 60% to 80% of your one rep max. Resting should be short, at about 60 seconds. Training volume should then increase to 12 to 28 sets per muscle, per week.

Safety Tips

While nutrition and training are important for getting the most out of your bulk period, you are still putting your body under greater stress. It is essential to prioritize sleep, hydration, and stress management in addition to nutrition and training to help your body recover, repair, and reach your muscle gain goals.

If you are following a traditional—or dirty bulk—for a long period of time, you are putting yourself at risk of gaining excess body fat and increased health risks. Because of this, traditional bulks are better utilized in the short term.

Additionally, rapid weight gain can put pressure on joints and cause stretch marks. Remember to take your time and work toward putting on muscle slowly to prevent rapid weight gain and the risk factors associated with it.

A Word From Verywell

It is possible to bulk without following a strategic diet plan. However, attempting a bulk without a strength training routine or by eating primarily ultra-processed foods can leave you with more fat than muscle gain.

If you're serious about building muscle and want to do it in a way that maximizes your training efforts with minimal fat gain, combining a clean bulk with a consistent strength training program is the way to go. But, determining how many calories, the types of foods, and developing a training program is not easy to do on your own.

If that is the case for you, a certified strength and conditioning coach or personal trainer and registered dietitian can help you develop a routine and meal plan that fits your lifestyle and help you reach your goals. You also should talk to a medical professional, especially if you plan to exceed 2 grams of protein per kilogram of weight per day.

Frequently Asked Questions

  • Is bulking necessary to gain muscle?

    Bulking is not necessary for muscle gain. However, a bulking phase may help someone gain muscle faster.

  • Can you run while bulking?

    Remember, a calorie surplus is ideal for an effective bulking phase. You can run while bulking, just be sure you are not burning more calories than you are consuming. In fact, some aerobic exercise is beneficial for building muscle.

  • What should you eat while bulking?

    Technically, you can eat whatever you would like during a bulk. But to reduce body fat gain and increase lean muscle mass gain it is important to focus on a high protein diet followed by whole unprocessed foods including whole grains, legumes, beans, fruits, vegetables, nuts, seeds, oils, and the like.

11 Sources
Verywell Fit uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Iraki J, Fitschen P, Espinar S, Helms E. Nutrition recommendations for bodybuilders in the off-season: A narrative reviewSports. 2019;7(7):154. doi:10.3390/sports7070154

  2. Leaf A, Antonio J. The effects of overfeeding on body composition: The role of macronutrient composition - A Narrative ReviewInt J Exerc Sci. 2017;10(8):1275-1296. PMID:29399253

  3. Krzysztofik M, Wilk M, Wojdała G, Gołaś A. Maximizing muscle hypertrophy: A systematic review of advanced resistance training techniques and methodsInt J Environ Res Public Health. 2019;16(24):4897. doi:10.3390/ijerph16244897

  4. Boutcher SH. High-intensity intermittent exercise and fat lossJ Obes. 2011;2011:868305. doi:10.1155/2011/868305

  5. Callahan MJ, Parr EB, Hawley JA, Camera DM. Can high-intensity interval training promote skeletal muscle anabolism? Sports Med. 2021 Mar;51(3):405-421. doi:10.1007/s40279-020-01397-3.

  6. Krzysztofik, Wilk, Wojdała, Gołaś. Maximizing muscle hypertrophy: a systematic review of advanced resistance training techniques and methodsIJERPH. 2019;16(24):4897. doi:10.3390/ijerph16244897

  7. Prentice AM. Overeating: the health risks. Obes Res. 2001 Nov;9 Suppl 4:234S-238S. doi:10.1038/oby.2001.124 

  8. National Library of Medicine: Stretch marks.

  9. Okifuji A, Hare BD. The association between chronic pain and obesityJ Pain Res. 2015;8:399-408. Published 2015 Jul 14. doi:10.2147/JPR.S55598

  10. Slater GJ, Dieter BP, Marsh DJ, Helms ER, Shaw G, Iraki J. Is an energy surplus required to maximize skeletal muscle hypertrophy associated with resistance trainingFront Nutr. 2019;6:131. Published 2019 Aug 20. doi:10.3389/fnut.2019.00131

  11. Konopka AR, Harber MP. Skeletal muscle hypertrophy after aerobic exercise trainingExerc Sport Sci Rev. 2014;42(2):53-61. doi:10.1249/JES.0000000000000007

Additional Reading

By Shoshana Pritzker RD, CDN, CSSD, CISSN
Shoshana Pritzker RD, CDN is a sports and pediatric dietitian, the owner of Nutrition by Shoshana, and is the author of "Carb Cycling for Weight Loss." Shoshana received her B.S in dietetics and nutrition from Florida International University. She's been writing and creating content in the health, nutrition, and fitness space for over 15 years and is regularly featured in Oxygen Magazine, JennyCraig.com, and more.