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How do I calculate my ideal calorie deficit?

A calorie deficit is a portion of calories deducted from your TDEE ( total daily energy expenditure) - the amount of calories we use every day to function and fuel activity.

Creating a deficit will put your energy requirements into negative equity forcing your body to use stored energy (primarily body fat) to make up the difference and fuel your body as needed.

We can create a deficit either by cutting calories, increasing activity (as long as food isn't increased still a consideration) or ideally both and as body composition is 80% nutrition it's a strong competitor for achieving your desired goal.

So here's how you calculate your individualised calorie requirments-

* First you need to work out your BMR (basal metabolic rate) this is what your body needs purely to function without activity

The Harris Benedict Equation is the most popular method and is as follows:-

WOMEN - BMR= (10 x weight in KG) + (6.25 x height in cm) - (5 x age in years) -161

MEN- BMR= (10 x weight in KG) + (6.25 x height in cm) - ( 5x age in years) + 5

Now we have your BMR say for instance its 1300 kcals for example purposes

You now need to work out your TDEE (total daily energy expenditure) the guide is as follows:-

*Little to no activity = BMR x 1.2

*Little exercise = (1-3 days per week), or a moderately active job i.e. hairdresser and no exercise = BMR x 1.375

*Moderate exercise (3-5 days per week), or light exercise and a moderately active job, or heavy exercise and an inactive job = BMR x 1.55

*Heavy exercise (5 days per week hard training), or moderately active job i.e. postman and moderate exercise = BMR x 1.725

*Very hard exercise (twice per day , extra heavy workouts), or someone with a very active job i.e. building site worker who exercises a lot = BMR x 1.9

Example- My BMR is 1300 kcals, I workout 3 days a week and work as a hairdresser. I would put myself in the moderately active category meaning I need to calculate

BMR = 1300 x 1.55 = 2015 kcals

This shows me an estimate of how many calories I need per day to maintain my weight.

Finally you need to decide on a deficit. This usually falls in between a 10-30% decrease in calories.

I have decided on a 15% calorie deficit as I'd like a nice steady weight loss but without too much deprivation this would take me to a daily calorie goal of 1712 kcals lets call it 1700 kcals and a weekly amount of 11900 kcals. You can really be flexible with this, the most important number is the weekly amount. Maybe you'd prefer slighty higher calories on a training day then up it by 200 kcals and reduce a rest day by 200 kcals. Just remember your target for the week.

Keep in mind that this needs to be sustainable so although the larger deficit will have more rapid results will you be able to adhere to it without feeling absolutely miserable?

I prefer to put my clients on around a 20% deficit or a possible short 30% at the beginning of their weight loss journey, then decrease to 15-20% for the majority.

It really is trial and error to see what works for you. Take note of hunger, energy, cravings and sleep and remember consistancy is key.

* Keep protein a priority throughout to help maintain as much muscle mass as possible as well as all the other benefits. ( post on this comming soon)

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