By the end of this article you will learn how to calculate how much of your daily calories should come from carbohydrates, protein and fat.
Macronutrient: Quick overview
Fats are made up of molecules called triglycerides and are an incredibly important macronutrient.They are responsible for many essential processes including synthesising hormones, insulation, absorption of fat-soluble vitamins (A, D, E, and K) and protecting vital body organs.When you consume fats, your body digests it, breaks it down and passes it into your bloodstream.Then, you either use the broken-down fat for energy or it gets stored in your fat tissue.
I’m sure many of you have already noticed that the human body can store fat in huge quantities!On average people can store between 50,000 and 100,000 calories (kcal) of fat.
To help put that into more perspective, that’s also the equivalent of 100 – 200 McDonalds Big Macs!You can also store an additional 3000kcal of fat in your muscles (about 6 Big Macs).
As annoying as this may be if you want to be shredded for your summer holidays, this is vital for survival.The good news is, you can burn fat through exercise and here are the factors that determine how much you can burn:
Duration of your exercise
(as duration increases, there is a greater reliance on fat as a source of fuel)
Intensity of your exercise
(fat is your main source of fuel at lower intensities such as walking. At high intensity, your source of fuel is carbohydrate)
(if you’re highly trained, you have a higher capacity to burn fat to fuel your exercise; saving your carbohydrate stores for later, allowing you to perform for longer)
(If you don’t have enough carbohydrates, your body must turn to fat to keep you going. However, if your exercise is high-intensity, fat is not your preferred source of fuel and your performance will be significantly impaired)
Fat is very energy dense! 1g of fat = 9kcal
As such, I recommend you keep fat intake to a minimum. But not too low, remember it is essential for survival. So how much do you need? Stick around to find out.
Proteins are made from a sequence of building blocks – amino acids. There are 20 amino acids and 9 are ‘essential’ meaning you must get them from your diet!
Protein is not as energy dense as fats; 1g of protein = 4 kcal
They are vital for building, repairing and maintaining lean mass and more and more studies are now supporting a high protein diet for weight loss to preserve your lean mass whilst cutting fat.Don’t worry, I will show you how much protein you need in just a sec.
Carbohydrates are made from monosaccharides (single molecule of sugar) with the most abundant being glucose.The main storage form of glucose is glycogen.Muscle glycogen is the main fuel for your muscles during higher intensity exercise; liver glycogen is a backup storage of glucose; and blood glucose (blood sugar) is the main source of fuel for your brain.
Unlike fat, carbohydrates cannot be stored in such large amounts in your body.Carbs are also not as energy dense as fats; 1g of carbohydrate = 4 kcal
I have come across many athletes and non-athletes who try to avoid carbohydrates, but you MUST understand its importance. Later in this article, I will show you how much carbohydrates athletes need for different sports. You won’t believe it!
So, how much of each macronutrient do YOU need?
To answer this question you need to first find out how many calories you burn every single day of the week. Use an online total daily energy expenditure (TDEE) calculator to find out.
Once you know this, you can calculate how much of your calories should be made up of each macronutrient, according to your body weight: g/kg body weight.
Aim for 0.8g – 1.2g/kg body weight/day Let’s use myself as an example:
I weigh 73kg.
0.8g x 73kg = 58g fat/day
1.2g x 73kg = 88g fat/day
So that’s my range and I will track this using MyFitnessPal.
You should keep protein anywhere from 1.0 – 2.0g/kg/day; depending on your activity level (see the table below)
For me, I need to aim for the upper end of the range: 1.8g – 2.0g/kg/day.
1.8g x 73kg = 131g protein/day
2.0g x 73kg = 146g protein/day
So, I can eat anywhere from 130g – 150g protein a day and I will track this using MyFitnessPal.
H’S TOP TIP: Spread your protein intake up throughout the day and aim for approximately 20-30g protein with every meal (roughly every 3 – 4 hours)!
So far with my example, we know fat and protein intake will be relatively consistent every day, so the only one left to manipulate is carbs.
This will naturally be determined by my activity level for each day.
What the hell am I talking about!?
Now, this may seem complicated at first, but carbohydrate manipulation is a simple yet, powerful way to fuel your performance and maintain optimum physique.
So, remember how I said 1g fat = 9kcal; 1g protein = 4kcal and 1g carb = 4kcal?
We are going to use this to calculate how many grams of carbohydrate you need every day and the best way to illustrate this is to use another table.
This table is my own real-life example, using a rest day and a training day.
Here’s how to calculate yours:
Step 1 – Calculate how many calories you will burn that day.
Step 2 – You know fat and protein remain consistent, so go ahead and enter the values in.
Step 3 – Calculate how many calories your protein and fat intake add up to.
1g fat = 9 kcal: 73g (fat) x 9 (kcal) = 657 kcal.
1g protein = 4 kcal: 146g (protein) x 4 (kcal) = 584 kcal.
657 + 584 = 1241 kcal
Are you still with me?
Step 4 – Calculate how many calories you have left to eat for that day.
Rest day: 2100 (kcal) – 1241 (kcal) = 859 kcal
1g carb = 4 kcal: 859 (kcal) ÷ 4 (kcal) = 215g
Training day: 3000 (kcal) – 1241 (kcal) = 1759 kcal
1g carb = 4 kcal: 1759 (kcal) ÷ 4 (kcal) = 440g
On my training day, I cycle for 30 minutes and lift weights for 60-90 minutes at moderate to high intensity.
So, it makes sense I need more than double the carbs compared to my rest day, right? 440g vs 215g!
Remember this is just something to aim for.
Is it possible to eat like this every day?
Unless you’re an elite athlete with clear a competition goal and deadline, an excellent support staff and/or a lot of money behind you, it isn’t too easy.
So, don’t beat yourself up if one day your fat was too high, or protein was too low. Just stay on top it as much as you can. The more you stay on top it, the quicker you will reach your goals. As promised earlier, I wanted to show you the carbohydrate guidelines from Professor Louise Burke for athletes in different sports:
To put this into perspective, a 70kg tour de France cyclists will be aiming for 700 – 840g carbohydrates in a day! Sometimes even more!
That’s the equivalent 35 – 40 bananas in a day… Whilst cycling!
The bottom line is do not be afraid of carbs! They will not make you fat! Only eating more than what you need will lead to unwanted fat gain!
That’s why these calculations are so important!
Calculate your total daily energy expenditure for each day,
Keep fat consistently low (roughly 1g/kg/day)
Keep protein consistently high (between 1 – 2g/kg/day)
Use carbohydrate to meet the remainder of your daily caloric target!
Automatically, on rest days you will have low carbs and on training days, high carbs.
Thank you for reading, I hope this was valuable and something to consider.
What did you learn from this article? Did you know this method of calculating your macronutrients?
Curious to hear your thoughts in the comments.
Houman is a performance nutritionist working with elite athletes as well as coaching non-athletes to develop the daily habits that will guarantee life-long results. With a BSc in Nutrition and Exercise Science, MSc in Sport Nutrition and Level 3 Personal Trainer, Houman has always been passionate about helping people look, feel and perform their best.