CSCS How to Calculate a Calorie Surplus for Muscle Gain for Athletes

May 06, 2024

Edited by: Danielle Abel

If you or your athletes have never gone into a calorie surplus or bulking phase to help build lean muscle mass and strength, getting started might feel overwhelming. But surplus phases are really similar to calorie deficit (cutting) phases, in which these phases are intended to be short-term, strategic timeframes that help an individual meet a specific and measurable outcome. 

The cool thing about bulking is that you get to do the complete opposite of what you do in a cut. For example, during a diet or calorie deficit, you might increase your fiber intake very high to help you stay satiated, whereas in a bulk, you may intentionally choose foods that are lower in fiber to help you consume more energy from calorically dense foods. 

Now, this doesn't mean that going into bulk is a time to eat non-nutrient-dense, "junk" food, either. Sure, you'll have extra calories to play around with, but getting adequate micronutrients is just as important during this time as any other time of year. 

The National Strength and Conditioning Association's (NSCA) Essentials of Strength Training and Conditioning Textbook, 4th edition, has a very short paragraph on weight gain for athletes. In this article, we'll break down what may be helpful to know about bulking for athletes to help you pass the exam and apply the concept practically. 

What is a Calorie Surplus?

As the name suggests, a surplus is simply eating above your maintenance level of intake from a total calories per day perspective. Calorie surplus phases are also known as "bulking phases" within the fitness industry. Creating a calorie surplus is typically done in 2 parts:

  • Calculate estimated TDEE (total daily energy expenditure) 
  • Determine what % above TDEE you will initially start at

Keep in mind, if someone is consuming significantly less than where their estimated TDEE is, then they may need to increase their intake first, over a few weeks or more before officially starting the surplus. 

Typically, a calorie surplus is created by increasing the amount of carbohydrates consumed. It may also be created through an increase in carbohydrates and protein, depending on where protein intake is at near the start of the surplus. 

A calorie surplus is typically what most athletes need nutritionally to build muscle tissue. Some athletes can build muscle at maintenance, but often, it's athletes with a year or two or less of resistance training experience. It's important to recognize that calorie surplus phases are intended to be time-bound, meaning they won't eat like that forever. A good target timeframe might be anywhere from 10 to 16 weeks. 

Keep in mind that it's possible to do shorter "sprints" and take surplus breaks in between. For example, 3-4 weeks of a surplus followed by 1-2 weeks at maintenance, repeated. 

How Do You Calculate a Calorie Surplus?

You'll first need to calculate their estimated TDEE. According to the NSCA, you can use the Cunningham equation, Harris-Benedict equation or Table 10.4 on page 217 of the textbook. If you don't know how to use these equations, this article entitled "Calculating Calorie Needs for Athletes" can help. Then, you'll need to calculate what their surplus calories & macros will be. 

Once you have the athletes estimated TDEE, you'll need to choose a percentage rate above their TDEE to aim for. Here are some considerations to help:

  • Anywhere from 5-15% is pretty common
  • You could set the % and keep it there, or you could gradually increase it every 2-4 weeks
  • Having a feel for how the client feels about weight gain might help you determine a starting %, for example, someone who is nervous might need to start at a low rate

Here's an example of what this might look like -An athlete whose maintenance calories, or TDEE, are calculated at 2345:

  • 5% increase above TDEE = 117 calorie increase per day = 2462 calories/day
  • 10% increase above TDEE = 235 calorie increase per day = 2580 calories/day
  • 15 % increase above TDEE = 352 calorie increase per day = 2697 calories/day

Setting Macros in a Surplus

Once you've set the athlete's calories, you'll want to set their protein, carbs, and fats, also referred to as macronutrients. For athletes in a surplus, these are some parameters that can help:

  • According to the NSCA, athletes who want to gain weight should set their protein between 1.5g/kg of body weight and 2.0g/kg of body weight
  • Fats should still stay within the recommended range of 20-35% 
  • The remaining calories left after you've set protein & fats should be allocated to carbs

Using the 10% surplus above TDEE example from above (2580 calories/day), here's what a 75kg athlete's macros might look like:

  • 75kg x 1.7g/kg = 128g of protein
  • 2580 calories x 20% = 516 calories or 57g of fats (to get 57 take 516 divided by 9 for 9 calories in every 1 gram of fat)
  • On the upper end, the athlete's fat macros could be as high as 30% or 774 calories per day, or 86g of fat per day
  • Once you have protein & carbs set, you'll take the remaining calories and divide by 4 to get your grams of carbs
    • Protein calories - 128 x 4 = 512
    • 20% fat calories = 516 calories from fat
    • 512 protein calories + 516 fat calories = 1028 calories
    • Now take 2580 calories per day - 1028 = 1552 calories available for carbs
    • 1552 divided by 4 (4 calories per 1 gram of carbs) = 388g of carbs per day

Here's how their calories and macros would look per day:

  • 2580 calories
  • 128g of protein
  • 388g of carbs
  • 57g of fat

How Do You Know If You're In a Calorie Surplus?

The main indicator used to tell if someone is actually in a calorie surplus is body weight gain. However, there are other ways of measuring your body's response to the surplus that could be combined with scale weight to make the surplus phase a bit more focused on performance:

  • Body weight or measurements are regularly increasing or body composition photos are changing
  • Strength is improving
  • Other types of performance are improving

Do You Have to Track Calories & Macros in a Calorie Surplus?

If someone doesn't want to track their intake during a surplus phase, that's ok. It could be helpful to calculate their estimated TDEE, have them track for a week or two to see where their intake is coming in on average, and then slowly work towards reducing tracking until they're not tracking at all.

Keep in mind that you'll probably want to identify at least one outcome goal of the surplus phase to help the athlete determine their success in the surplus. Similar to what we said above, this could be body weight, increased measurements, changes in body composition photos, strength gains, or other types of improved performance.  


Support & Courses Available

Ready for more support to help you prep for the CSCS exam? Join our Facebook Group, “Strength and Conditioning Study Group,” here. Ready for even more? Our 24-module CSCS Prep Course has the nutrition chapters, 9 and 10, completely laid out for you with even more content than what we’ve provided here, plus chapter quizzes to help you pass the NSCA exam; click the link here to check it out.

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