im getting really confussed about my daily intake or 1400, I want to find my BMR again and work out my maintance and see what 500 below that is,
Can anyone help me with the calcutaions ive tried a few on the net and i dont know how accurate they are,
age 20 84kg and 5 foot 7 i think??
My main convern is when i get down to my goal of 70kg i dont want my maintance to be low, The body gets used to calorie expenditure?
There are a number of different equations and calculators you can use to get an ESTIMATE on your calorie requirements.
This is from Emma-Leigh's site and are the equations that I use for my clients and have used for a number of years -
Estimating Requirements
The simplest method of estimating needs is to base your intake on a standard 'calories per unit of weight (usually kilograms)'. Typically this is:
- 25 to 30 kcals/kg/day for normal, healthy individuals with sedentary lifestyles doing little physical activity [11.5-13.5 kcal/pound]
- 30 to 35 kcal/kg/day for those involved in light to moderate activity 3-5 x a week with moderately active lifestyles [13.5-16 kcal/ pound]
- 35 to 40 kcals/kg/day for those involved in vigorous activity and highly active jobs [16-18 kcal/ pound].
There are then a number of more complex formula which calculate BMR based on any number of variables including sex, height, weight, age, and lean mass. This BMR is then multiplied by an 'activity variable' to give TEE. To go over a few BMR calculations:
1/ Harris-Benedict formula:
Men: BMR = 66 + [13.7 x weight (kg)] + [5 x height (cm)] - [6.76 x age (years)]
Women: BMR = 655 + [9.6 x weight (kg)] + [1.8 x height (cm)] - [4.7 x age (years)]
This formula is particularly inaccurate - It was derived from studies using lean males in a cold lab many years ago (1919). It is notorious for overestimating calorie requirements, especially in those that are overweight and inactive. IF YOU WANT AN ACCURATE READING, DON'T USE IT!
2/Mifflin-St Jeor:
For MEN: BMR = [9.99 x weight (kg)] + [6.25 x height (cm)] - [4.92 x age (years)] + 5
For WOMEN: BMR = [9.99 x weight (kg)] + [6.25 x height (cm)] - [4.92 x age (years)] -161
This formula was developed in the 1990s. It is much more accurate than the above as it is more realistic in todays lifestyle settings.... However, it still does not take into consideration the difference in metabolic rate as a consequence of high BF%. Thus, once again, it also overestimates needs in highly obese individuals. So - once again, if you use it, be warned it can OVERESTIMATE your needs.
3/Katch-McArdle:
BMR = 370 + (21.6 x LBM)
Where LBM = [total weight (kg) x (100 - bodyfat %)]/100
This is considered the most accurate formula for those who are relatively lean and who have a good understanding of their bodyfat %.
To then convert to a TEE you multiply the BMR from the above equations by an Activity Factor
1.2 = Sedentary (Little or no exercise and desk job)
1.3-1.4 = Lightly Active (Light exercise or sports 1-3 days a week)
1.5-1.6 = Moderately Active (Moderate exercise or sports 3-5 days a week)
1.7-1.8 = Very Active (Hard exercise or sports 6-7 days a week)
1.9-2.0 = Extremely Active (Hard daily exercise or sports and physical job)
(note: these activity factors generally include a TEF of ~ 15% - which is an average mixed diet).
Just How Accurate are they?
Unfortunately, many people rely on these generic 'online calculations' to calculate how many calories they need... And although they can (sometimes) give rough ball-park figures, they are rarely accurate. Most people OVERESTIMATE their activity factor, and UNDERESTIMATE their bodyfat - and end up eating TOO MUCH. So - you are better off starting with these 'rough figures' and then monitoring your weight/ measurements for 2-4 weeks. IF your weight is stable/ measurements are stable, then you have likely found your maintenance intake.
Using the Above to Recalculate Based on Goals
Taking the above, you will then need to DECREASE or INCREASE intake based on your goals of INCREASING mass or DECREASING mass. For this - instead of using 'generic calorie amounts' (eg: 500 cals/ day to lose weight) I would recommend starting with adding/ subtracting based on a % of your maintenance - reason being is that the effect of a given calorie amount on an individual is going to be markedly different based on their size/ total calorie intake.... For example - subtracting 500 cals/ day from a 115# females 1500 total intake is 1/3rd of her total cals but 500 cals/ day for a 215# male on 3500 total intake is only 1/6th of their total... And it will result in markedly different effects on their energy levels and weight loss.
Generally speaking:
-> to ADD weight: ADD 10-20% calories to your total from above
-> to LOSE weight: SUBTRACT 10-20% calories from your total from above
Then monitor your results and adjust as required.
Emma-Leigh
MFP = myfitnesspal. Iphone & Android apps and it's free. Doesn't give macro %'s breakdown and the reporting isn't as good as fitday or calorieking but it does the job for me. And a pretty good social community thing over there as well.