You've read the title and in your head you've done jazz hands haven't you......
But seriously, if you want to know how many calories you should be eating to either build muscle or loose fat you'll want to read this!
I hear this so often: "How many calories should I eat?"
The question is asked so often when I have a new client start with me that I could make my millions if I got a tenner for every time it was asked.
The answer to the question bluntly - it depends!
Do you want to build muscle or loose fat or do you simply want to maintain your current weight?
Different goals require a different calorie intake, and then to further complicate this every person is completely different, even if say for instance 2 people are kind of the same age height and weight and have similar body types, their calorie needs could be completely different.
This is way I always offer a completely bespoke program, as their isnt a one size fits all to that common question of how many calories should I eat?
But despair not my fellow K3 Fitness UK crew, as Im gong to show you how I calculate the number of calories you need for YOUR body based on YOUR GOALS!
I know Im too generous, but at the end of the day I want you all to be the best versions you can be and without the correct tools and knowledge its not going to happen....
So if your goal is to gain muscle mass, drop some fat , do some body re sculpting or find out how to perform better, the information below can help you.
And its all begins with the TDEE.
What the hell is that I hear you all ask, well TDEE stands for Total Daily Energy Expenditure. It is the total number of calories you burn in a given day. Your TDEE is determined by four key factors:
Basal Metabolic Rate
Thermic Effect of Food
Non-Exercise Activity Thermogenesis
Thermic Effect of Activity (Exercise)
Now your screaming at me going what does all that shit mean??
let me explain:
Basal Metabolic Rate (BMR)
Basal metabolic rate refers to the number of calories your body burns each day to keep you alive. BMR does not include physical activity, the process of digestion, or things like walking from one room to another.
Basically, BMR is the number of calories your body would expend in a 24 hour period if all you did was lay in bed all day long. This is the absolute bare minimum of calories it takes to ensure your survival.
Thermic Effect of Food (TEF)
When we eat food, our body must expend energy to digest the food we eat. This energy expenditure is referred to as the Thermic Effect of Food, and it involves breaking down the protein, carbohydrates, and fat you consume into the individual amino acids, sugars, and fatty acids that are then absorbed and used to by the body to carry out all of its processes including (but not limited to) building new tissue, synthesizing hormones, producing neurotransmitters, etc.
Research notes that the Thermic Effect of Food generally accounts for 10% of your total daily energy expenditure, but can be slightly higher or lower based on the exact macronutrient composition of your diet.[1]
For example, protein requires more energy to digest than carbohydrates or fat. So, if you’re eating a high protein diet, you will burn more calories, slightly, than if you were to eat the same number of calories, but with a significantly lower amount of protein.
Non-Exercise Activity Thermogenesis (NEAT)
Non-exercise Activity Thermogenesis (NEAT) constitutes the number of calories expended during daily movement that is not categorized as structured exercise. NEAT includes activities such as walking the dog, moving from one room to another, or taking the stairs to your office.
NEAT is highly variable from one person to another and can play a rather large or small role in your overall TDEE depending on how physically active your job or daily happenings are. For example, a waitress or construction worker will have a significantly greater NEAT than an office worker who sits at a desk for 8 hours of the day and spends 2 hours commuting to and from work.
Thermic Effect of Activity (TEA)
Thermic Effect of Activity is the number of calories burned as a result of exercise (i.e. steady-state cardio, resistance training, HIIT, sprints, CrossFit, etc.). Similar to NEAT, thermic effect of exercise is highly variable from one person to another or even from one day to another for the same person, as the intensity of training, length of the workout, and training frequency all impact your weekly thermic effect of activity.
Your TDEE is the sum of these four factors, so to put the above parameters into a math equation for simplicity sake, calculating TDEE looks a little something like this:
TDEE = BMR + TEF + NEAT + TEA
now lets take a look how to calculate all this things:
How to Calculate TDEE
Figuring out your total daily energy expenditure begins with calculating your BMR. The reason we’re starting with BMR is that it contributes the biggest portion of your TDEE.
Now, there are a lot of handy calculators readily available on the internet for calculating BMR as well as TDEE. But, the way to truly understand how those fancy calculators work is by understanding the equations powering them.
So, that’s exactly what we’re going to do.
Calculating Basal Metabolic Rate
Researchers have developed a number of models for calculating BMR, and one of the most popular ones is the Harris-Benedict Equation, which takes into account age, height, and weight.
Here’s a step-by-step guide to calculate your BMR using the Harris-Benedict Equation:
Women BMR = 655 + (9.6 X weight in kg) + (1.8 x height in cm) – (4.7 x age in yrs)
Men BMR = 66 + (13.7 X weight in kg) + (5 x height in cm) – (6.8G4* x age in yrs)
As an example, let’s take a 30-year-old male named John who is 6 feet tall and weighs 185 lbs.
So, John’s stats converting from imperial units to metric yields:
Age: 30
Height: 6’0” = 72 inches = 182.88cm (to convert inches to centimeters, multiply your height in inches by 2.54)
Weight: 185 lbs = 84.09kg (to convert pounds to kilograms, divide your weight in pounds by 2.2)
Using the Harris-Benedict Equation for men, and plugging the above numbers into the equation gives you:
BMR = 66 + (13.7 x 84.09) + (5 x 182.88) – (6.8 x 30)
BMR = 66 + 1152.03 + 914.4 – 204
BMR = 1928.43
So, as a bare minimum to sustain life and ensure longevity, our example male John would need to consume roughly ~1930 calories.
The next step in figuring out TDEE would be to calculate the thermic effect of food as well as the non-exercise and exercise factors. However, these calculations are extremely tedious and the equations to model the caloric expenditure each requires isn’t the most reliable.
Fortunately, you don’t have to spend hours performing more tedious calculations. You don’t even have to use a fitness monitor or rely on those erroneous “Calories Burned” readouts on cardio machines to figure out the rest of the components of your TDEE.
Researchers have determined a set of “activity multipliers, known as the Katch-McArdle multipliers.
To calculate your approximate TDEE, simply multiply these activity factors by your BMR:
Sedentary (little to no exercise + work a desk job) = 1.2
Lightly Active (light exercise 1-3 days / week) = 1.375
Moderately Active (moderate exercise 3-5 days / week) = 1.55
Very Active (heavy exercise 6-7 days / week) = 1.725
Extremely Active (very heavy exercise, hard labor job, training 2x / day) = 1.9
Going back to our example guy John, let’s assume he trains 3 days per week following a high-frequency full body training program with no additional steady-state cardio or HIIT training during the week. This puts John in the “Moderately Active” category.
To calculate John’s approximate TDEE, multiply his BMR by 1.55. This gives us:
TDEE = 1.55 x BMR
TDEE = 1.55 x 1928.43
TDEE = 2989.07
So, our example guy John needs to consume about 2990 calories each day just to maintain his current weight.
Now, at this point, it’s important we stress that these equations and activity multipliers provide AN ESTIMATE for your daily calorie requirements.
That is, your actual TDEE could be a little higher or lower than the number you calculate when you use the formula. But, it should be fairly close, and at the very least, it gives you a rough idea of where to start when figuring out a meal plan and setting macronutrient goals.
Speaking of goals, now let’s look at how you can use your TDEE to enhance your body composition whether it be for muscle gain or fat loss.
Manipulating TDEE for Muscle Gain and Fat Loss
So, how does knowing your TDEE help you gain muscle or lose fat?
While there’s endless debate in the fitness world about the “optimal” way to go about reshaping your body, this much is true:
If you want to lose fat, you need to eat fewer calories than your TDEE. Doing so forces your body to draw energy from its fat stores to compensate for the calories you’re not consuming each day. Do this long enough and you will lose weight and body fat
If you want to gain muscle mass, you need to eat more calories than your TDEE. To gain weight, you must be in a caloric surplus. Coupled with a rigorous training program following the principles of progressive overload, those extra calories will be put to building new muscle tissue.
Now, let’s see how to put this into practice
For Fat Loss
To lose fat, we typically recommend that using a caloric deficit of 20% (but generally not more than 300 calories when starting out - even more so without under the supervision of a coach)
Muscle Gain
Gaining weight, and preferably muscle, requires consuming more calories than your body expends on a daily basis. When combined with a structured resistance training program, a caloric surplus provides the essential nutrients needed to optimize performance and build muscle.
For the longest time, it was preached that in order to get big, you had to eat big too. But, as sports nutrition has developed over the years, lifters and researchers alike have learned that the surplus needed to build lean muscle tissue isn’t a huge as we were once led to believe.
Simply put, the body can synthesize a finite amount of muscle tissue at any given time. That means that eating substantially more than what is required to build new muscle just leads to excess fat gain. Therefore, the trick to minimizing fat gain while trying to build muscle is to use a moderate calorie surplus, giving your body just enough to grow bigger, stronger, and faster, without getting fatter. This approach to muscle gain is known today as lean bulking.
To build muscle and limit fat gain, you need to consume roughly 200-300 calories above your TDEE.
Thoughts
Total daily energy expenditure is the number of calories your body burns in a given day taking everything into account from sleep to digestion to exercise.
TDEE calculators offer a way for you to figure out a close approximation to the actual number of calories you burn in a day, which you can then use to structure a diet for building muscle or burning fat.
Through proper manipulation and application of your TDEE, you have the power to reshape your body in your own ideal image and never ever have to settle for another cookie cutter meal plan or diet protocol. When knowing how many calories you need to eat for muscle gain or fat loss, you can eat the foods you enjoy while adhering to the calorie and macronutrient goals you set.
The saying goes “with knowledge comes power.” Well, I’ve now given you the knowledge and power to start creating the best version of you, now all you need is a coach to keep you going and to create a bespoke program for training and eating.
References
Tappy, L. (1996). Thermic effect of food and sympathetic nervous system activity in humans. Reproduction, Nutrition, Development, 36(4), 391–397. http://www.ncbi.nlm.nih.gov/pubmed/8878356
Now your just spoiling us 🥰. Interesting read and very helpful, thanks doll xx