Joined today - very confused!

digital_davem
digital_davem Posts: 6
in Getting Started
Hi Folks

Just joined the journey. Hoping to lose up to a 100 lbs.

But things have not started well. I'm confused as to how MFP works. Hope you can help.

Two questions:

1. I have set up my account and I have synchronised with my my brand new Fitbit zip account. I'm recording all my calories eaten in the Myfitness pal food diary but I'm entering no exercise information. The exercise information is coming from Fitbit exclusively.

What I would expect to happen is that my Home screen would then show my calorie goal for the day, the food calories consumed (from my diary) minus the exercise calories (imported from Fitbit) and calculate the deficit. That is exactly what it does on my partner's account.

However, mine is doing something different. It is *** adding *** the exercise calories to the food calories as if the exercise was eating! The more exercise I do, the fatter I get according to the MFP calculator.

Can someone explain why it is doing this?

2. How does MFP arrive at it's goal calories per day figure? I have supplied my age, height, weight, declared myself as sedentary so it obviously uses this somehow. But what is its basis for calculating the daily figure - is it based on some official tables for the average person or something?

Thanks for any help

Regards

David

Replies

  • mygrl4meee
    mygrl4meee Posts: 943 Member
    If you told my fitness pal your goal is to lose weight then it gave you an calorie goal that will make you lose weight just by diet alone. When you workout it gives you the calories back so your not running too low. For example my goal is 1500 a day. If I burn off 900 during my workouts that is leaving me with only 600 calories to function on which isn't good or easy to keep up long term. I have a fitbit and sometimes it gives me credit for being active but then takes it back the next day. Its something I just don't get. So unless I have been. Super active I am trying to ignore majority of those exercise calories. You won't gain weight by eating them back. As long it really was an workout. Any exercise you do you can personally log it and it will not double count it. Hope I helped.
  • CynthiaT60
    CynthiaT60 Posts: 1,280 Member
    At the beginning of the day you might notice "added" calories from Fitbit. Don't worry about it. Check later in the day and you should see that it's starting to subtract.
    (There are lots of threads about this in the Fitbit part of MFP; they explain this in detail.)

    Good luck!
  • jwaters1006
    jwaters1006 Posts: 136 Member
    Fitbit and mfp "talk" so if mfp estimates your calorie burn as 3600 for the day, but fitbit is telling it you'll only burn 3300 for the day it will add 300 calories. Basically it's telling you to move more! You can also still add you exercise to mfp, just be sure to add the Times reflected on fitbit. I have a fitbit one and I'm on here daily, please feel free to add me!
  • yarwell
    yarwell Posts: 10,477 Member
    1. Fitbit tells MFP of extra activity above the basic assumption. MFP's "method" is to retain the original goal you set so if you exercise more then you're prompted to eat more. It's a bit like a hamster wheel with food as the reward. Doesn't seem entirely logical if weight loss is your overwhelming requirement.

    2. Your Basal metabolic rate in calories is calculated from a published correlation using height/weight etc, multiplied by 1.2 for sedentary activity and 500 calories per day are subtracted from that for each 1 pound/week of weight loss you told it.
  • digital_davem
    digital_davem Posts: 6
    Thanks for the replies, just trying to work through the logic of this.

    Is this correct:

    1. MFP first works out your BMR based on your supplied height, weight age from published data (source?)
    .
    2. It then uses the activity level you supply (in my case I've put sedentary as I have a desk job) to scale your BMR by an arbitrary figure (in this case x1.2) to arrive at an estimate of the daily calories you require to maintain your weight.

    3. It then uses your desired rate of weight loss to estimate the calorie reduction you need daily and deducts this from the maintenance calorie estimate to arrive at an allocation for the day that if adhered to will achieve that loss over the long term.

    4. If you record additional exercise in your diary or via fitbit, your daily calorie allocation is increased i.e. you've earned the right to eat more while still losing weight at your desired rate.

    This leaves me with some additional questions:

    1. What is the source evidence MFP uses to calculate BMR

    2. What is the justification for the scaling factor for the self assessed activity level (is this just made up by MFP as a guess or is there some sound justification for it)

    3. Is the method of calculating the required daily deficit (-500 calories per day = 1 pound loss) reasonable.. It is commonly quoted in the diet industry but I saw a BBC story last year about a peer reviewed study that claims these industry figures were all wrong and that when your experimental subjects were monitored around the clock, the actual weight loss is in reality about half what the industry claims it should be and that dieting is actually much more difficult than even everyone claims it is).

    4. Would I be better off not synching my fitbit and manually transferring the exercise details from fitbit at the end of every day into the MFP diary rather than worrying about the weird numbers it inputs.

    Phew, thanks for listening. Sorry to be so fussy but if i'm going to hitch my wagon to MFP, I want to be sure I completely understand what the numbers mean so I can manage my expectations.

    Cheers

    D

    1. Fitbit tells MFP of extra activity above the basic assumption. MFP's "method" is to retain the original goal you set so if you exercise more then you're prompted to eat more. It's a bit like a hamster wheel with food as the reward. Doesn't seem entirely logical if weight loss is your overwhelming requirement.

    2. Your Basal metabolic rate in calories is calculated from a published correlation using height/weight etc, multiplied by 1.2 for sedentary activity and 500 calories per day are subtracted from that for each 1 pound/week of weight loss you told it.
  • editorgrrl
    editorgrrl Posts: 7,060 Member
    MFP has a Fitbit Users group: http://www.myfitnesspal.com/forums/show/1307-fitbit-users

    When you set up your MFP account, you specified an activity level: http://www.myfitnesspal.com/account/change_goals_guided MFP used your answer, plus your age, sex & height, to estimate how many calories you burn every day (not including exercise). Then you set your weight-loss goal, and MFP subtracted the appropriate deficit to calculate your daily calorie goal.

    Once you link an activity tracker to your MFP account (via the "Apps" tab at the top of every page), you start getting calorie adjustments. If your tracker says you burned more calories than MFP estimated, you get a positive adjustment (meaning more calories to eat). If you enable negative calorie adjustments and you burn less than the MFP estimate, you will lose calories. (But negative calorie adjustments will never drop your daily calories below 1,200.)

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