Athletic performance and success is based on preparation to match and surpass the demands required of you during competition. One of those factors that athletes miss out on is: intentionally looking at their daily eating habits to ensure they are not in an unintentional caloric deficit. Why does this matter? Calories = energy. Having a vital resource such as energy = higher levels of performance AND decreased injury risk. That’s why we put together this quick article to teach you simple ways to track your calories and avoid unintentional deficits. 

What Is A Caloric Deficit?

A calorie is a unit of measure related to energy. When you eat calories, you are receiving energy; when you exercise, you are using energy aka burning calories. If the energy you are expending is greater than the energy you are consuming, you are in a deficit. 

The simple formula of a caloric deficit is: ↓energy intake + ↑ energy output = caloric deficit

The formula of a caloric surplus to gain weight is the exact opposite: ↑ energy intake + ↓ energy output = caloric surplus

Some deficits are intentional to lose weight but most of the time athletes during the season will fall into a deficit unknowingly. This inhibits performance and increases the chance of injury significantly. You can change that simply by knowing what your target maintenance calories are and then tracking how many calories you consume and how much is going out. It’s a numbers game, let’s teach you how to play it:

Finding Your Maintenance Calories

To maintain your current weight, a simple rule of thumb is to use your body weight (in lbs) multiplied by 15. For example, a 140 lb athlete x15 = 2,100 calories per day to maintain the weight of 140 lb. 

You can take the next step by establishing your targets for macros (carbs, fats, protein). A good goal in-season for an athlete is that Carbs = 50-60%, Proteins = 25-30%, and Fats = 20-25% of the total calories. 

Now that you have a target calorie number to hit, you want to track your calories to see how close you are to that maintenance number.

Simple Ways To Track Your Calories

As we stated before, It’s a numbers game; if you don’t have the numbers, you are just guessing. When it comes to athletic performance and injuries, I don’t know about you, but I don’t like guessing; I like knowing.

Start with simple ways to track your calories by recording what you eat each day for a week. Yes, it takes effort, but if it keeps you performing and out of sports rehab, it’s worth it. With that said, we are not oblivious to the reality of how tedious this can be. To decrease the barrier to entry, here’s what we do with our athletes:

• Serve your food using measuring cups so you know how much the portion truly is. Example: Scooping rice; use a 1 cup measuring spoon so you know exactly how much is on your plate.

• Paper log: Have a scrap piece of paper on which you write down everything you eat in the day. Don’t worry about counting the calories or macros (carbs, proteins, fats), just write it down with the portion sizes.

• Use AI: We have access to technology; why not use it? At the end of the day, put into Chat GPT what you ate and ask it to calculate your total calories for the day and the macros.

Best practice is measuring each food on a scale and using the nutrition label to do your own math, but again, we need to decrease the barrier of entry, and we have found that AI in this case is fairly accurate (not so much in other cases). 

Simple Ways To Determine Caloric Expenditure

You can use the calculation we provided above: Body weight (lbs) x 15, OR you can dive into establishing your basal metabolic rate + activity energy expenditure. 

More Complex Method: Estimate Your Basal Metabolic Rate (BMR)

Your BMR is the number of calories your body needs at rest to maintain basic functions like breathing, circulation, and cell repair. It depends on your age, gender, weight, and height.

One of the most commonly used formulas is the Mifflin-St Jeor Equation:

Men:

• BMR = 10 × weight(kg) + 6.25 × height(cm) – 5 × age(y) + 5

Women:

• BMR = 10 × weight(kg) + 6.25 × height(cm) – 5 × age(y) – 161

Example (Male, 75 kg, 180 cm, 25 years old):

• BMR = 10×75 + 6.25×180 – 5×25 + 5 = 750 + 1125 – 125 + 5 = 1755 kcal/day

Estimate Your Activity Expenditure

Having a wearable like Garmin or Whoop is helpful, but again, we have other resources available; let’s use them. You can type your activity with the intensity you trained at, duration, etc, into Chat GPT and it will give you a fairly good estimate of your activity energy expenditure. 

You would then take your (Activity expenditure + BMR) = Total expenditure. 

Now you have your target maintenance calories, caloric intake, and caloric output. 

Final Steps

Compare your caloric intake to your target intake to determine where you stand. By reviewing your calories in vs. calories out, you can quickly identify whether you’re maintaining, in a deficit, or in a surplus.

It might feel overwhelming at first, or like you don’t have time, but the reality is we make time for what we prioritize. Shifting just 20–30 minutes away from mindless scrolling can free up the time you need to focus on something that directly supports your performance.

FAQ: Caloric Deficits and Athletic Performance

1. What is a caloric deficit, and why does it matter for athletes?

A caloric deficit occurs when energy output exceeds energy intake. For athletes, unknowingly being in a deficit can decrease performance and increase injury risk.

2. How can athletes track their caloric intake effectively?

Athletes can use simple methods like measuring cups, a paper food log, or AI tools to record and calculate daily calories and macros. Accuracy improves when using a scale and nutrition labels.

3. How do athletes determine their maintenance calories and energy expenditure?

Maintenance calories can be estimated using body weight × 15, or more precisely by calculating Basal Metabolic Rate (BMR) and adding activity energy expenditure from workouts, wearables, or tracking tools.

Ready to max out your life’s potential?

The Hope Hub shares weekly insights that help go-getters become high performers: 📩 [Subscribe to our newsletter].

Author: 

Dr. Dillon Caswell, PT, DPT, SCS

Doctor of Physical Therapy | Board Certified Sports Specialist

Hope Evangelist | Top-Selling Author & Speaker | Human Performance Expert