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How to Calculate a Calorie Deficit


Are you ready to take charge of your physical health and get in shape? If so, creating a healthy calorie deficit, along with your three workouts per week at 9Round, can help you get there.

Don't let the challenge of calorie tracking hold you back from unlocking your full potential. We've got you covered with a nifty equation that can guide you in determining your ideal caloric deficit to help you track your nutrition goals effectively. So, buckle up and get ready to crunch the numbers with us!

One of the most accurate and well-known formulas for finding your caloric deficit is the Mifflin-St. Jeor equation. This is a formula that calculates your Basal Metabolic Rate (BMR), which is the number of calories your body burns at rest. This equation considers several factors, including age, sex, weight, and height, making it a highly accurate way to calculate your BMR.

The formula for the Mifflin-St Jeor equation is as follows:

  • For men: BMR = (10 x weight in kg) + (6.25 x height in cm) - (5 x age in years) + 5
  • For women: BMR = (10 x weight in kg) + (6.25 x height in cm) - (5 x age in years) - 161

Once you've calculated your BMR using the Mifflin-St. Jeor equation, you can determine your Total Daily Energy Expenditure (TDEE). Your TDEE is the total number of calories you burn in a day, including your BMR and physical activity. To determine your TDEE, you need to multiply your BMR by an activity factor that represents your level of physical activity. The activity factors are as follows:

  • Sedentary (little or no exercise) = BMR x 1.2
  • Lightly active (light exercise or sports 1-3 days a week) = BMR x 1.375
  • Moderately active (moderate exercise or sports 3-5 days a week) = BMR x 1.55
  • Very active (hard exercise or sports 6-7 days a week) = BMR x 1.725
  • Extra active (very hard exercise or sports, physical job or training twice a day) = BMR x 1.9

Now that you know all the formulas required to calculate a caloric deficit, let’s walk through an example together.

Suppose you’re a moderately active woman who works out at 9Round three times a week, is 30 years old, weighs 150 pounds and is 5'5" tall. In that case, your BMR is 1,400 calories, calculated using the Mifflin-St. Jeor equation.

To determine your TDEE, you need to multiply your BMR by an activity factor that represents your level of physical activity. Since you're moderately active, you will use an activity factor of 1.55. Therefore, your TDEE is 2,170 calories (1,400 x 1.55). This means your body burns around 2,170 calories per day, including your BMR and physical activity.

To create a healthy calorie deficit, you can subtract 300 to 500 calories from your TDEE. Based on this information, the moderately active women in our example above would want to consume between 1870 and 1670 calories per day to create a healthy calorie deficit. However, it's crucial to avoid creating too large a deficit, as it can slow down your metabolism and lead to muscle loss.

Remember, everyone's calorie needs are different, and it's important to listen to your body and adjust your intake and activity levels according to what helps you feel best. The goal is to create positive habits that are sustainable and easy to track for the long run, so you can maintain a healthy weight without undoing your hard work down the line.

Once you calculate your calorie deficit, you can make gradual adjustments to your diet and physical activity levels to achieve your weight loss goals.

Start by tracking your current calorie intake and activity levels to get a baseline—food and workout journals are a great option for this. Then, aim to reduce your daily calorie intake gradually until you’re hitting the calorie deficit you determined using the formulas above. You can do this by choosing healthier foods, reducing portion sizes, and cutting out high-calorie snacks and drinks.

Before we wrap things up, it’s important to note that while monitoring calories on their own will initially help you make progress, you will likely need to address your macronutrient breakdown as well. This is the amount of carbs, protein, and fat you’re consuming with each meal.

Learning how to balance these macronutrients is trickier than simply reducing calories but it’s a crucial next step for balancing your nutrition. We explain more about macronutrients in our 9Round Nutrition Guide, which you can access in your 9Round Member Portal.

Now that you’re armed with this knowledge, you can calculate your ideal calorie deficit and set up a sustainable and healthy weight loss plan with regular exercise included. Remember, patience and consistency are the keys to success, so keep kickin’ and stay motivated to achieve your goals.

For the best results, we strongly recommend working with a Registered Dietician if you want to dive deeper into your nutrition goals and create a plan of action that works alongside your KILLER workouts at 9Round.

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