Help with the math? (TDEE, BMR, etc.)

Hi all, I recently read this post http://www.myfitnesspal.com/topics/show/654536-in-place-of-a-road-map-2-0-revised-7-2-12 and figured I should get on track with more precise numbers of calories to consume based on my personal measurements. Up till now I've tried eating 1200 calories a day (miserable, but the scale moves and measurements change when I include exercise) and eating at a smaller weight loss per week setting (ended up around 1600 calories per day, didn't see the scale moving much or measurements changing even with exercise). I did the math according to that page and was shocked with the numbers it gave me. Could you all check to see if my numbers are right, and confirm how much I should be eating a day?

I work a desk job, but do Pilates 2x a week, running 1-3x a week, and weight-lifting with a trainer 2x a week. I really want to lose fat and get lean, so... Help, please!

Here are my stats:

Age: 25
Gender: Female
Height: 62 inches
CW: 183 pounds
GW: 130 pounds
Neck circumference: 13.7 inches
Waist circumference: 38.1 inches
Hip circumference: 53.1 inches

I plugged those numbers into the recommended fat % calculator on the "In Place of a Road Map" page and got:

Body Fat %: 54.9% (yikes)

Then I plugged that and all my measurements into the BMR calculator recommended by the page and got:

TDEE: 2234 calories/day
BMR: 1917 calories/day (when I input 130 pounds as goal weight)

I'm just not sure how much I should be eating... Any suggestions are much appreciated!

Replies

  • Put in your current weight not your goal weight (that step is on the post you just read, but it's quite small and easy to miss) and see waht you come back with
  • ekr2107
    ekr2107 Posts: 23 Member
    Thanks for your reply. I did put in my current weight and that's where I got the number 2234. I got 1917 when I plugged in my goal weight. I'm just not sure what number to use...
  • 3foldchord
    3foldchord Posts: 2,918 Member
    I think 'they' recommend your TDEE (2234) minus 20% (4458.6) which is 1787(.2) c alories a day.

    just using the formula I read, guessing I did it right. (Still figuring out what numbers work for me)
  • geekyjock76
    geekyjock76 Posts: 2,720 Member
    こんにちは!

    I'm questioning that body fat prediction of 54.9%. At your present weight, that would imply your lean body mass is a mere 83 lbs which is very low at 5'2" but within believable range if you naturally have a very petite build.

    Anyway, accepting that BF%, I get a BMR of 1184 with the Katch McKardle equation and 1625 with the Harris Benedict equation when entering 130 goal weight. So you'd get an estimated TDEE range of 1629 to 2234 depending on which equation you go by with light activity. If I use the formula by Institute of Medicine Dietary Reference Intakes, I get a TDEE of 2538.

    As you can see, TDEE formulas can have very broad ranges of recommended caloric intake. I would guess your TDEE is likely closer to 2234 than 2538 so you could take a 25% deficit from that. So that would be 1675 (559 deficit) net. That would be roughly a 1 lb per week loss in body weight. You COULD do an initial short-term deficit of 30% (670) then reduce it to 25% once you lose the first 10 lbs since you have 50 lbs to lose. That would start you off closer to 1.3 lbs the first week or so.

    Thus, if you wish to apply the 559 calorie deficit, you could eat 360 calories under TDEE (1874) and engage in a total of 200 exercise calories. If you do the 670 deficit to start, then eat 470 below TDEE (1764) and keep the 200 exercise calories burn. Again, if you start with the 30% deficit, reduce it to 25% once you lose the first 10 lbs.

    Do you have a HRM to track exercise energy expenditure? It would help more accurately estimate the amount of deficit exercise contributes.

    頑張って。
  • trixiemou
    trixiemou Posts: 554 Member
    Hi, you could check out fat2fitradio, they have numerous calculators on there.
  • Thanks for your reply. I did put in my current weight and that's where I got the number 2234. I got 1917 when I plugged in my goal weight. I'm just not sure what number to use...

    Cool.
    Use your current weight (because you're eating for the current you, not the future you).
    Then as you lose weight go back and re-do the calculations. How often you go back and re-do the calculations is up to you. Hope that helps
  • Koldnomore
    Koldnomore Posts: 1,613 Member
    Thanks for your reply. I did put in my current weight and that's where I got the number 2234. I got 1917 when I plugged in my goal weight. I'm just not sure what number to use...

    Cool.
    Use your current weight (because you're eating for the current you, not the future you).
    Then as you lose weight go back and re-do the calculations. How often you go back and re-do the calculations is up to you. Hope that helps

    OR you could just base it on 'future you' which is just as valid ;) Then you don't have to mess with adjusting anything. I use Scooby http://scoobysworkshop.com/calorie-calculator/
    According to this, you need 1666 to maintain GOAL weight and your current BMR 1619. Thus eat about 1700 and if you work out ALWAYS eat back calories to at LEAST 1619. This is for sedentary (which you are not) There is a spreadsheet where you can input more exact numbers for your workouts but the principle is just as valid. Look here for the method: http://www.myfitnesspal.com/topics/show/477666-eating-for-future-you-method

    Because everyone is different there is no 'right' way. You will likely have to tweak whatever method you choose to fit you.

    Good luck!
  • teez52
    teez52 Posts: 104 Member
    I don't trust a website to do math for me so I'll take care of the hard part for you, here is the Mifflin - St. Jeor formula:

    Stats:
    Age: 25
    Gender: Female
    Height: 62 inches = 157.5cm
    CW: 183 pounds = 83kg
    GW: 130 pounds = Irrelevant for these calculations
    Neck circumference: 13.7 inches = Irrelevant for these calculations
    Waist circumference: 38.1 inches = Irrelevant for these calculations
    Hip circumference: 53.1 inches= Irrelevant for these calculations

    Math:
    BMR= (9.99 * 83) + (6.25 * 157.5) - (4.92 * 25) - 161
    BMR = 1529.55

    TDEE = BMR * Activity Factor
    TDEE = 1529.55 * 1.3
    TDEE = 1988.41

    Activity Factors:

    1.2 = Sedentary (Desk job, and Little Formal Exercise)
    1.3-1.4 = Lightly Active (Light daily activity AND light exercise 1-3 days a week)
    1.5-1.6 = Moderately Active (Moderately daily Activity & Moderate exercise 3-5 days a week)
    1.7-1.8 = Very Active (Physically demanding lifestyle & Hard exercise 6-7 days a week)
    1.9-2.2 = Extremely Active (Athlete in ENDURANCE training or VERY HARD physical job)

    TDEE is how much you spend a day doing your normal activities. For me, I keep my activity factor at 1.2 just to be safe if I don't have time to actually weigh my food that I eat. On a side note, that's one of the most important things to do on a diet, otherwise how do you know how many calories you're actually eating?

    Now that we have that in check let's see how much you should eat to lose weight, given that a pound = 3500cal, to lose 1 pound a week you would need to cut 3500cal per week which means 3500/7 = 500/day deficit. The math is simple from there, if you want to lose 1 pound a week:

    Goal Calories = TDEE - 500 (for 1 lb/week)
    Goal Calories = 1988.41-500 = 1488.41

    Or you can do a percentage

    Goal Calories = TDEE (.9)
    Goal Calories = 1988.41 * 0.9 = 1789.57

    OR

    Goal Calories = TDEE * 0.8
    Goal calories = 1988.41 * 0.8 = 1590.73

    Take it or leave it, but this is the real math and it doesn't lie as long as your stats you gave us were correct. And don't forget as you lose weight, you'll need to adjust your goal calories based on your current weight because they will be different now than they will be when you're down to 150 or 130. This is why people see their weightloss slow down as they get lower in weight, you need less calories the less you weigh so it's simple logic.
  • Crayvn
    Crayvn Posts: 390 Member
    Hello all..i got a whiff of this TDEE concept and have been trying it since Tuesday..man it feels good to eat above 1200 calories. It feels more natural to eat according to the formula.

    However, I only just started MPF a few weeks ago and lost 5 lbs in 2 wks. on MFP 1200 cals. Do you think i might not loose this week while my body adjusts to the extra calories.? I am not new to loosing alot of weight.....this is my 2nd go around. And im fairly confident that I will loose the weight using the TDEE formula based on all the feedback and testimonials. I just need my hand held til I get used to it hehehehe. As im sure many have said before, it seems like so much food ..i get nervous :p
  • ekr2107
    ekr2107 Posts: 23 Member
    Hello everyone! Sorry for my late reply, and thank you so much for your generous responses. I feel much more educated on the matter of BMR/TDEE thanks to all of you ^^ It seems like a pretty inexact science (unless you can shell out the money for a professional evaluation, which would need to be constantly reformulated anyways with steady weightloss), but for the time being I understand my BMR to be in the range of 1600 calories a day, which is what MPF has me set at to lose 1 pound a week. I'm going to stick with this for a while to see how it works. Thanks again!
  • RetiredAndLovingIt
    RetiredAndLovingIt Posts: 1,395 Member
    bump
  • jlsoules
    jlsoules Posts: 86 Member
    Bump for later....
  • ExplorinLauren
    ExplorinLauren Posts: 991 Member
    Glad you posted this :)

    I'm kind of in the same boat... read the In place of a road map thread...Read a lot more posts than that! Asked lots of questions... even posted my own forum question, trying to figure it all out... and after a long thread, where people argued over what was right and what was wrong.... then the dreaded below or above BMR, or What MFP says vs. 15-20 % below TDEE... blah blah...

    I finally decided based on everything I would do 15-20% below TDEE... For me that is 2400-2600 calories a day... I find that hard to believe. Esp considering a "normal diet" is 2500 cals a day. 20% of that is still eating 1900-2000 cals a day. I can't convince myself that I can eat that and still lose. Maybe I'm just a baby, and can't grasp that yet lol IDK... All I do know... is that I can't figure out the math either... and even when I think I have it figured out, I really don't. lol
  • teez52
    teez52 Posts: 104 Member
    Glad you posted this :)

    I'm kind of in the same boat... read the In place of a road map thread...Read a lot more posts than that! Asked lots of questions... even posted my own forum question, trying to figure it all out... and after a long thread, where people argued over what was right and what was wrong.... then the dreaded below or above BMR, or What MFP says vs. 15-20 % below TDEE... blah blah...

    I finally decided based on everything I would do 15-20% below TDEE... For me that is 2400-2600 calories a day... I find that hard to believe. Esp considering a "normal diet" is 2500 cals a day. 20% of that is still eating 1900-2000 cals a day. I can't convince myself that I can eat that and still lose. Maybe I'm just a baby, and can't grasp that yet lol IDK... All I do know... is that I can't figure out the math either... and even when I think I have it figured out, I really don't. lol

    The math is simple, I posted the exact math about 5 posts above yours along with how to do it all! If you can't do it, PM me and I can walk you through it and get you on the right track.