Top Menu

calories in vs out

Calculating your calories in vs calories out

The simple science behind weight loss
There is no amazing secret that lies behind losing weight. It comes down to one simple formula:

Calories in (Eaten)

needs to be less than

Calories out (Used through exercise)

which creates what is known as a ‘calorific deficit’.

As long as you are following this formula to create a calorific deficit you will lose weight. Obviously things get more advanced than this but that tends to matter more for people taking part in body aesthetic competitions or those really wanting to fine tune their appearance. However for general weight loss for the basics are all that matters.

How long does it take to lose 1lb of Fat
1 pound (0.454 kg’s) of Fat is roughly equal to 3500 calories. This means that by taking on a calorific deficit of 500 calories per day, around 1 pound of fat can be burned per week. This works out at 4 pounds (1.8 kg’s) per month. At this rate it is possible to lose 5.4 kg or even up to around 1 stone (6.3 kg’s) in 12 weeks.

In 6 months you can lose 10.8kg or 1.7 stone.

In 12 months you can lose 21.6kg or 3.4 stone.

Imagine the difference you could make to your appearance if you set your mind to it!!

Why not just crash diet and lose the weight even quicker?
Whilst initially you will lose a lot of weight quickly, your body will soon start to sense that it is not getting suitable nourishment and will begin to hold on to the weight, then as soon as you start to eat normally again your weight will rebound back on to a greater level than it was before. It is very important to lose weight at a safe and consistent rate rather than just to starve yourself, that is if you want to retain your progress.

There are 2 main things you need to know in the following order:

    1. How many calories you are using (burn as many as possible with boxing training)
    2. How many calories you are taking in (what you are eating)

The first thing we are going to cover is how many calories you are using.

How many calories are you using?
The first thing you need to know is how many calories your body is consuming for general day to day living. This falls into two categories:

  1. Basal metabolic rate (how many calories your body uses just to function when doing nothing, such as energy for breathing and pumping your heart and powering your metabolism etc)
  2. Physical activity ratio (Do you sit around or are you up on your feet all day for example)

The two categories are then used to calculate your average TOTAL DAILY ENERGY EXPENDITURE (TDEE).

Calorie calculator
As calculating you calories manually can be tricky if your not great with maths we have done the hard work for you and created a simple easy to use calculator. Simply input your details to get the results.

MWP Diet Calorie Calculator


Total Daily Energy Expenditure








Workout Calories


Rest Calories

Before using the data obtained using this calculator, please consult with doctor.

Calculating your calorie target
Once you know your TDEE you need to work out your calorie target in order for you to create a calorific deficit. A 15-20% deficit is a good place to start. This may be higher or lower depending on starting body fat levels, personal goals and energy requirements. (We are aiming for a 500 calorie per day deficit but for practicality purposes get as close to this figure as possible).

It’s important to remember that regardless of what approach you take, your calorie target is an estimation, not an exact number. Even if you follow all the advice to the letter, it’s still an estimation and some tweaking may be necessary. 

Additional calories burnt through exercise
So now you know how many calories are being burned by your body just to simply function. We are aiming to take on around a 500 calories deficit per day (3500 per week) or burn an additional 500 calories per day so this means that any exercise done will contribute towards that figure.

Why exercise at all, is it not easier to simply change my diet.
The simple answer is that yes you will get results from only dieting alone but the benefits you get will be far less. 

The benefits you will get from physical exercise will contribute greatly to your overall results with things such as:

  • Improved muscle tone and lean muscle mass
  • Improved heart function
  • Improved lung function
  • Improved immune system
  • Stress relief
  • Improved skin tone and health

The other important aspect of improving your fitness for weight loss is that the fitter you are, the harder and longer you can work out for which means you will be able to burn more calories per session.

Calculating calories burned
The total number of calories burned for any task is calculated by first finding the calorie burn per hour. First of all you have to know what the Metabolic equivalent of task (MET value) of the activity is.

Once you have figured out how many calories you are burning with each workout you can factor that into your calories target.

An interesting study on desk jobs and calorie burn
Something interesting for you to note is a study that was performed on people who sit at their desks all day during work. Their calorie burn level went down to around only 1 calorie per hour! If you sit at your desk all day at work and then go home and spend the rest of the evening sitting in front of the tv, imagine the effect this will have on your metabolism and weight!

Factoring in your workouts to your calorie target.
Bearing in mind that we want to create a 3500 calorie a week deficit, if you train 3 times per week and burn 300 calories in each workout (total 900 calories per week) that means you only have to cut your diet down to 2600 calories per week to achieve the same results. On saying that the best results will occur if you manage to stick to nutritional calorie target then the calories burned from your workouts will have an even greater effect.

For example if your TDEE is 2136 and you do a 300 calorie workout that means your TDEE will be 2436 per day. If you are then only consuming 1706 calories that makes a total deficit of 730 calories per day. 

Something to think about…

Calculating your calorie intake
Now that we know how to calculate your calorie target and calories burned you also need to know how to calculate your calorie intake, also known as nutrition. Nutrition is actually the most important aspect of losing weight. So important in fact that around 80% of your results will come from having the correct diet. As the saying goes, ‘you can’t out train a bad diet’. 

If you would like to know how to calculate your calorie intake please register your email address below for a copy of the Boxing Evolution FREE nutrition report.



[wps_products tag= “e-book” page_size=”3″ items_per_row=”3″ excludes=”pricing, description”]

Boxing Evolution has the perfect solution with our very own ‘Zero to Hero’ boxing body transformation course.

You will learn about all the different aspects of weight loss, nutrition (including monthly recipes) and developing fitness along with learning real boxing skills. There is no better way to lose weight and get in shape than with boxing!

For more information please check out the ‘Learn More’button below.

Learn More


Comments are closed.