Day 1.4: Truth In Numbers - Daily Caloric Needs

Happy Thursday!  Are you spending as much time in the little girls' room as I am?  Whew.  Every time I increase my water intake, I feel like  the "gotta go right now" commercial.  Your skin is thanking you for all the clean, hydrating water you're drinking.  Just don't drink after dinner if you don't wanna be up all night.  Ugh.  Fear not, keep drinking and your body will adjust to all the extra fluids.  Drinking water also burns fat, ta-da!  I worked my abs, thanks to Kathryn, and I'm pretty much sore all over. Sweet!

I love fitness data.  I love seeing what my BMI is.  I love putting in my goal weight and seeing what my BMI would be, if only I had some self control.  Sigh.  I love scales that read body fat percentage.  I love heart rate monitors and GPS distance devices that tell me mileage and speed.  I pretty much love any form of fitness data.  I'm a junkie.  Why?  Because numbers don't lie.  It's not for everyone, but it can be very useful in your journey.



Information is power.

Here are some terms you should know:

BMR: Basal Metabolic Rate is how many calories you burn just living.

BMI: Body Mass Index is your weight to height ratio.

TDEE: Daily calorie needs, based on BMR, age, current weight, and activity levels.  This is where you start, then reduce calories to a weight loss level.  Another method is based on body weight alone.

We've started with a basic 1400 calorie diet in the First 10 Days.  As our eating habits improve and our activity levels increase, we can adjust to find the right caloric intake to lose weight but feel energized enough to keep moving, and work harder.

BMR:  Follow this link to find out how many calories you burn just living.  http://www.myfitnesspal.com/tools/bmr-calculator

BMI: Follow this link to find out what your BMI is.
http://www.nhlbi.nih.gov/guidelines/obesity/BMI/bmicalc.htm
The National Heart Lung and Blood Institute (gross) has set up a weight range that is healthy for your height.  Play with it enterting different higher and lower weights and notice the broad range for your height.  Somewhere in that range you will find your happy weight, or personally sustainable weight.  You know when you are too heavy, even if it falls into the acceptable healthy weight category on NHLBI.  The reason for the broad weight ranges is to account for the fact that muscle weighs more than fat.  My healthy weight range is 115-154 lbs. (what the?!)  NOT HEALTHY on either side of the range if I am 40% body fat.  I wouldn't worry about being at the high end if I'm muscular and under 20% body fat.

Ok.

Daily Caloric Needs:  Get ready for some serious math, girls. There are six components that determine how many calories you need each day: BMR, activity level, weight, lean body mass (muscle, or LBM), age and gender.

Math 101 version:
to achieve Fat loss = 12-13 calories per pound of body weight (140 lbs x 12=1680 cal per day)
to Maintain (TDEE) = 15-16 calories per pound of body weight (140 lbs x 15 = 2100 cal per day)
to Gain Weight  = 18-20+ calories per pound of body weight (140 lbs x 18 = 2520 cal per day)

Math 401 version: (get a pencil and paper, a TI-84 calculator, and your junior high student)
Women: BMR = 655 + (9.6 x weight in KG) + (1.8 x height in CM) - (4.7 x age in years)
This is a link to a metric conversion calculator: http://www.metric-conversions.org/

1. Convert your height in inches to centimeters, and your weight in pounds to kilograms.  Write these two numbers down.
2.  Write out the above equation filling in the two metric numbers you converted, IN THE CORRECT PLACE.
3.  Remember the order of operations and do the math inside the parentheses first.
4.  Now do the whole equation.
5.  Congratulations!  You now know your BMR, the basic number of calories you need to live.

Deep breath, and no weeping.  If you're arguing with your junior high student over methods, separate, please.  One more step.

TDEE:

Take your BMR that you just figured out.  Then use the following table to adjust for your activity level to find your TDEE (Total Daily Energy Expenditure):

Activity Factor:
Sedentery = BMR x 1.2
Lightly Active = BMR x 1.375
Moderately Active = BMR x 1.55
Very Active = BMR x 1.725
Extremety Active = BMR x 1.9

Be honest.  Walking up and down the stairs 20 times per day does not make you Very Active.  Neither does cleaning house, chasing kids (unless you are sprinting), or standing at the sink doing dishes.  I'm always looking for an excuse to eat more calories, because I need to stay alive, right?  Overestimating your activity level will just sabotage your fat loss efforts.

For me, it ended up like this:

BMR = 655 + (9.6 x 62kg)   + (1.8 x 167.64cm) - (4.7 x 37 years)
BMR = 655 + 595.2 + 301.75 - 173.9
BMR = 1378 calories per day to be a functioning body

Now I multiply by my activity factor, which I would say is Moderately Active 9 (yesterday, if I'm honest, sedentary) , and I get to eat 2136 calories per day to maintain my current weight.  If I see the scale stubbornly staying at 138 I KNOW I am eating this many calories.  Fact.

Notice how the age portion of the equation indicates that the older we are the more calories we are subtracting from our daily total needs.  The older you are the less you burn so the less you need.  Boohoo.

Another Fact: if you want to lose weight you have to eat less than your TDEE.   Eat 500 calories or 15-20% less calories than TDEE to lose weight and not move into starvation mode.  Myfitnesspal suggests that the minimum daily caloric intake for a woman is 1200 calories.  Lower than that and you are not doing yourself any favors: you'll be hungry, your body will store fat, you won't be able to exercise effectively or efficiently,  you will lose muscle instead of build it.

And forgive me; you know how I adore math.


Information is power, ladies.  Use it to kill it today!