Calories per day required!

My wife went to weight watchers last night and came home and told me about the points system. It’s basically calorie counting, but they have devised a points system to simplify it.

Basically, from what I can gather it works out at about 50 calories per point with some adjustment for fiber. With an added 7 points a day for each hour or of exercise according to weight watchers I should be consuming 32 points, plus 7 per hour of physical activity according to this. So, on a full exercise day I should be consuming 46 points, or 2300 calories.

1 - Male, Female or Nursing Mom?
Female – 2 points
Male – 8 points
Nursing Mom – 12 points

2 - Your Age17 – 26 = 4 Points
27 - 37 = 3 Points
38 - 47 = 2 points
48 - 58 =1 point
58 and older = 0 points

3 - Your Weight
What ever you weigh take the first 2 digits and add them to your points range.
For example if you weight 210 you add 21 pointsIf under 100 pounds take the first digit.
98 lbs = 9

4 - Your Height
Under 5’ ft = 0 points
5’ 1” – 5’ 10” = 1 point
5’ 10” and taller = 2 points

5 - Daily Activity Level
How do you spend most of your day?
Mostly Sitting = 0 points
Occasional sitting but most standing = 2 points (Examples are housewife, cook, teacher, sales clerk.)
Walking mostly = 4 points (Examples are, waiter or mailman)
Hard physical labor = 6 points (Examples are, Gardener, construction or active nurses.)
Add up all categories and you have your new points range.

Now, for me personally that seemed extremely low. Interestingly after some calculations, this is actually very close to my Resting Metabolic Rate of 2216 Cals a day. See below. So, Weight Watchers are actually suggesting that with all my activity included I should actually only eat enough calories to sustain my body at zero activity. In other words, I lay in bed all day, and do not walk, talk or move in anyway, other than to breath.

How to work out your resting metabolic rate, (from www.t-nation.com)

I'd multiply this kilogram number (91 kg) by my percent of body fat. Remember, percents are really decimals so 5% equals 0.05, 12% bodyfat will be .12 etc.

Fat Mass = 91kg x 0.05 = 4.55kg FM

Next I subtract this fat mass number (4.55 kg) from my total body mass (91kg):

Fat Free Mass = 91kg - 4.55kg = 86.45kg

Therefore my fat free mass is 86.45 kilograms. From that I can determine my RMR. The formula for RMR is as follows:
Resting Metabolic Rate for Athletes (in calories per day) = 500 + 22 x fat free mass (in kilograms).
Again, for me, I'd multiply 22 times my fat free mass and add 500 to that number as shown below:
RMR= 22 x 86.45 + 500 = 2402

So mine is RMR x Activity Factor = 2216 calories x 1.5 = 3324 calories.

Now we need to include “Costs of Exercise Activity”:

we need to include the exercise that I do during the week, we calculate this with the following,

MET values for common activities:
high impact aerobics? 7low impact aerobics? 5
high intensity cycling? 12low intensity cycling? 3
high intensity walking - 6.5low intensity walking - 2.5
high intensity running? 18low intensity running? 7
circuit-type training? 8intense free weight lifting? 6moderate machine training? 3

So here's the formula:

Cost of Exercise Activity = Body Mass (in kg) x Duration (in hours) x MET value
And here's how I calculate it for myself:

Exercise Expenditure for weights = 5 METS X 90 x 1.5 hours = 675 calories
Exercise Expenditure for cardio = 3 METS X 90 kg x .5 hours = 135 calories

Meaning that I burn around 810 on the days that I going the gym, morning and evening.
If we divide this by the amount of days I actually train, we have something along the lines of,

Amount of running per week = 77 calories per day.
Amount of weight training per week = 578 per day.
Total amount per day = 655 per day for physical activity.

So, my grand total of calories required, with the amount of physical training, and life style is approximately 3979 calories per day.

TEF
Now, we need to account for the thermic effect of food, this basically means that digesting food, burns calories.
Nobody is really 100% sure about this but scientist recon it’s around RMR x 0.10.
So mine would be,

RMR (2200) x 0.10 = 220.

Grand Total (nearly)
So the grand total for my daily calories is somewhere around 4199 calories but I figure that I don’t have the resting metabolic rate of an athlete (as suggested in step one, working out RMR, the guy doing that claims he’s an athlete) so I will deducted 300 calories as a very rough guess.

So, my super duper, final finalized, no more adjustments required results is,

3900 calories per day.

Compared to weight watchers suggested calories of

2300 calories per day.