How to determine your daily calorie needs #3

Let’s review everything I’ve told you up until now.

We have a female teacher, who is 30 year old, 156cm tall and weighs 70kg. Her BMI is 28.76 and her BMR and AMR are 1476.8 and 1772.16 kcal respectively.

To lose 9 kg of body fat she needs to create a calorie deficit of 69300 kcal during her weight loss journey, with as little loss to the lean body mass as possible. If she creates a 500 kcal deficit every day, she will lose the weight in 138.6 days or roughly 5 months. But if she creates a deficit of 750 calories she will achieve her goal in 92.4 days or roughly 3 months.

But how can she create a calorie deficit? Think of calories as a currency. You have 1400 calories you can spend each day. If you spend more than that, you’ll be in a calorie debt to your body (you’ll fain fat) and if you manage to save a few calories, the bank (your body) will reward you with interest in the form of a slimmer and a healthier body.

For that she has 3 options and all three of them are very specific.

1.       Reduce her calorie intake

2.       Increase her physical activity

3.       Reduce her calorie intake and increase her physical activity

Let’s look at how to reduce your calorie intake.

You can reduce it simply by knowing how much energy your body needs during the day with your basal metabolic rate (BMR) and active metabolic rate (AMR).

If you don’t move around the whole day and just stay in bed, you need to consume the exact amount of calories as your body burns to keep your weight the same. If you consume more than you need, you will gain weight, but if you consume any less, your metabolism will start to slow down and your body will be in a state of shock. This happens with most people on diets. In this case the body shuts down and stores every calorie that it can get, because the metabolism switches to “survival mode”.

If our teacher eats 1476.8 calories she won’t gain weight, if she has more, she’ll gain weight in the form of fat. And if she has, let’s say, 1000 or even less calories, her whole metabolism will slow down and go into “survival mode”

[IMPORTANT NOTE: The lowest calorie allowance I would even dare to put a client is 1600 for men and 1200 for women. Still, this is done only for a short period of time and for clients that have a lot of weight to lose.]

If she is active that day, her calorie allowance is 1772.16 calories. If she eats more than that, she will gain weight. If she eats that exact amount she’ll stay the same and if she eats less than that, she’ll lose weight.

Simple isn’t it.

Onto the other option. What should her calories be, if she decides to move more during her day and decides to burn 500 extra calories with jogging?

In this case if she eats the same amount of calories as her AMR every day she will definitely lose weight on the days when she is running, because she has created a 500 calorie deficit.

And if she decides to watch what she is eating and is physically active with jogging and a bit of weightlifting?

In that case we add those 500 extra calories burned to her AMR (2272.16) and we get her modified AMR during the days when she works out. The same rule applies here, if she wants to lose weight, she needs to create a calorie deficit. If she wants to maintain her weight she needs to eat exactly that amount and if she wants to gain weight, she needs to eat a lot more.

But this option is the best and you know why? A part of her calorie intake goes to muscle repair and it also helps to build her muscle, which increases her lean body mass while decreasing her fat body mass (but only if she is doing some anaerobic training).

This last part is a bit trickier for people with about 5kg or less to lose, but for people with a lot of kg, regular physical activity combined with good diet is a way to go.

Until next time, stay strong and be kind. 

Picture taken from: http://tiny.cc/pgcnhw