Calories/Kilo: What's wrong with my calculations please?

I understand that there is approx 7700 calories per kilo of human fat.

So if I'm constrained to 1220 calories/day (my weight loss diet according to this site) and I theoretically do 9000 calories of exercise per day then I should lose about a kilo per day. Of course this is not likely to happen anytime in the near (or distant) future :-)

So how can I lose weight ie.

1 220 x 7 = 8 540 calories per week intake
- 2 000 calories per week exercise
=
6 500 Calories excess (approx 0.8 kilo per week weight gain surely)

I know it's only theoretical but it doesn't seem right, it means I have to do approx 15 000 calories of exercise to lose 1kg of wieght a week.

Can anyone please tell whats wrong with it.

Many thanks Preet

Replies

  • jludwick78
    jludwick78 Posts: 34 Member
    You have to lessen your caloric intake 3500 calories per week to lose 1 pound. 7000 for 2 pounds.
    If you eat 1220 calories/ day x 7 days = 8540 calories per week. If you are averaging a typical 2000 calorie/day diet to maintain weight that equals 14000 calories/ week to lose nothing. Therefore, theoretically 14000-8540= 5460 less calories per week. Throw in 1540 burned calories for exercise to reach a total of 7000 less calories per week and you should lose 2 pounds that week. Which is all you should lose a week anyway.

    So basically, you only need to burn 1540 in exercise calories per week and eat 1220 calories per day to lose 2 pounds per week.
    Make sense?

    I can only work in pounds. And not completely sure my math is right.
  • treetop57
    treetop57 Posts: 1,578 Member
    It looks like you haven't taken into account your basic metabolic rate (BMR), the energy (calories) your body uses just to stay alive. It looks like you are only taking into account the calories burnt in exercise, but most of the calories you burn are just keeping your body warm. For an average sized person, that's going to be around 1500 calories even if the person is in a coma.

    You can find an estimate of your BMR here: http://www.myfitnesspal.com/tools/bmr-calculator It's a function of weight, height, age, and gender.
  • froeschli
    froeschli Posts: 1,292 Member
    I understand that there is approx 7700 calories per kilo of human fat.

    So if I'm constrained to 1220 calories/day (my weight loss diet according to this site) and I theoretically do 9000 calories of exercise per day then I should lose about a kilo per day. Of course this is not likely to happen anytime in the near (or distant) future :-)

    So how can I lose weight ie.

    1 220 x 7 = 8 540 calories per week intake
    - 2 000 calories per week exercise
    =
    6 500 Calories excess (approx 0.8 kilo per week weight gain surely)

    I know it's only theoretical but it doesn't seem right, it means I have to do approx 15 000 calories of exercise to lose 1kg of wieght a week.

    Can anyone please tell whats wrong with it.

    Many thanks Preet

    what's wrong is that you are trying to create a calorie deficit from numbers that already represent a deficit.

    1. find out what your actual daily calorie expenditure is
    2. deduct 1100 (7700 divided by 7, IMO thats too much of a deficit, but hey, your health). that's the net number you are aiming for
    3. if the resulting number is below 1200, you're definitely being stupid to try and lose that much.
    4. make sure you eat back exercise calories.
  • treetop57
    treetop57 Posts: 1,578 Member
    1 220 x 7 = 8 540 calories per week intake
    - 2 000 calories per week exercise
    =
    6 500 Calories excess (approx 0.8 kilo per week weight gain surely)

    I know it's only theoretical but it doesn't seem right, it means I have to do approx 15 000 calories of exercise to lose 1kg of wieght a week.

    Can anyone please tell whats wrong with it.

    Many thanks Preet

    Using your numbers and subtracting a basic metabolic rate of 1500 calories per day:

    1 220 x 7 = 8 540 calories per week intake
    - 2 000 calories per week exercise
    -1 500 x 7 =10 500 calories per week BMR

    8 540 - 2 000 - 10 500 = -3960 calories per week

    That's a smaller weekly deficit than the 7700 for one kilogram per week, but getting closer. The additional difference is the calories burned in normal everyday tasks like getting out of bed, digesting food, walking around, and sitting at work. Those calories are accounted for by the activity factor (1.25 for a sedentary office worker).

    Calories out per day (not including exercise) = BMR * 1.25 = 1500 * 1.25 = 1875 per day or 13125 per week

    8 540 - 2 000 - 13 125 = -6585

    Closer and closer. You probably have a higher BMR than 1500 (you're bigger, taller, or young than the 1500 I assumed) or you have a more active life (greater activity factor than 1.25).

    Clear as mud?
  • Yanicka1
    Yanicka1 Posts: 4,564 Member
    Like everyone else said, you forgot that you are alive and moving. In order to live, you burn alot of calories. I would suggest you Google BMR and not eat less then the number given.
  • Thanks guys.. I understand what I was doing wrong.

    Just to be clear my intake has been defined my personal trainer so I'm not too concerned tha tthe amount small.