Active mins: MFP & Fitbit One don't agree

[SageShiatsu]

I usually go for a fast 30-40 min walk first thing in the morning before I do anything else, going up hills and the like. When I get home and sync my Fitbit, it'll tell me I've done, say 25 very active mins. However, when I then log this exercise in My Fitness Pal, the very active mins on the Fitbit site drop to maybe 3 or 4 mins.

In contrast, having synced my MFP and Fitbit accounts and enabled the 'allow Fitbit adjustment' option on MFP, I'm disappointed to find that whenever I log exercise on MFP, the Fitbit adjustment takes several hundred calories off my daily total.

Can't get my head around this - I can understand them having different calibrations or whatever, but I'd have thought if that was the case that one would be consistently higher than the other. I seem to be getting the worst of both worlds - MFP telling me via adjustment of very active mins that I've not been as active as Fitbit thinks I have, while Fitbit then tells MFP that I haven't been as active as MFP thinks I have, via calorie adjustment!

Anyone else come across this? I can just disable the Fitbit adjustment, or unlink the accounts of course; it's not bothering me all that much, but I'm just interested to see if other people have come across this and have any idea why it seems to take the worst scenario for both.

Cheers,

AliS

[Colinm39 · Accepted solution]

@SageShiatsu      Many Fitbit users only log Food into MFP and let Fitbit do what it is best at, tracking steps. When you bring physical activities across my MFP it has no idea of your speed of steps while you are walking/running. Fitbit calculates these every 60 seconds. When MFP brings those calories across they are averaged across the time period you selected and the one minute time frames are flattened and every likelihood your VAM has been turned into moderate activity.

I have copied  @slysam in on this because I don't use MFP and I have followed many of her explanations of your issue.

The image below is a typical Fitbit one minute activity graph which has 26 minutes of VAM out of 53 minutes. If I were to overwrite that with calories, like MFP would do there is a good chance the graph will be averaged/flattened and I will lose 26 minutes of VAM.

[SunsetRunner · Accepted solution]

I use both and as Colin mentioned most use MFP for logging food due to it's huge food data base, and log all activity here on Fitbit. The only exception is when I cycle. I use Endomondo and a heart rate monitor for that. Fitbit is my main data base and I simply use other apps to supplement it.

[Frenchie51]

I have the same dilema, I just ignore the numbers, I know what I do, vs the Fitbit.  I have a Fitbit Flex

[slysam · Accepted solution]

That is how it is supposed to work. The Fitbit Adjustment is calculated by MFP to correct your allowance to account for activity that MFP has no way of accounting for. It excludes your logged exercise because MFP already adds all those calories on top of your allowance. If it wasn't excluded from the "Fitbit Adjustment" it would be double counting the same activity calories. When I use to log exercise to MFP, I always deleted the fitbit adjustment to keep myself from getting confused because whatever it was will change next time it syncs to MFP. MFP recalculates the fitbit adjustment every time the two sync so it will return the correct amount next sync. I've personally found it works better for me not to log exercise on MFP though, it works better to log it here if I hae to log.

About the active minutes... Is there any specific reason that you log your walking on MFP? I generally would suggest not logging walking at all (to either account) unless you have a good reason in this case. When I log walking, I always lose any very active minutes because whatever was logged replaces fitbit's tracked data. With fitbit tracked activity, the Very Active Minutes (and moderately a ctive, lightly active) are based on how much you move each minute. With manually logged it is more average calorie burn per minute since the calories burned are evenly divided among the duration causing the flattening Colin mentioned. You would have lost the spikes in activity even if what was logged was the same as what fitbit would have credited. 

[AngelajmRN]

I have had my fitbit flex for about 3 weeks now.  I am also using MFP.  When I first started I was logging everything into MFP.  I was making all of my goals except the "get in the zone".  I have been under all the time.   After reading the responses to this post I started logging my activity into my fitbit and not MFP.  I went for a power walk this morning (40min) and mowed the lawn this afternoon (60min).  If I log this activity into fit bit only I do not get any VAM and I am over on my calories in vs calories out.  If I log the activity into MFP I have 92 VAM and am "in the zone".  

This is all very confusing.  I am really only using MFP for logging....not paying attention to what they tell me as far as calories left.  I have been at a deficit for fitbit and it is not too far off from MFP because they add back all the exercise calories.  I wish that there was a simpler answer to all this.  I really think I am going to stick with logging everything into MFP.  I am very visual so I am really enjoying the fitbit dashboard and presentation but it makes me feel like I am not achieving anything if I am not meeting "my goals" for the day.

[slysam]

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@AngelajmRN wrote:

I have had my fitbit flex for about 3 weeks now.  I am also using MFP.  When I first started I was logging everything into MFP.  I was making all of my goals except the "get in the zone".  I have been under all the time.   After reading the responses to this post I started logging my activity into my fitbit and not MFP.  I went for a power walk this morning (40min) and mowed the lawn this afternoon (60min).  If I log this activity into fit bit only I do not get any VAM and I am over on my calories in vs calories out.  If I log the activity into MFP I have 92 VAM and am "in the zone".  

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It sounds like MFP just estimates a higher calorie burn for the activities than fitbit's activity database. Both are just using some averages adjusted for weight. I found that MFP was more generous with calorie burn  when I looked up a few activities recently (I lost my Fitbit so ocassionally have been logging activity). Personally, I feel MFP's estimates for activity calorie burn are too high as they are always higher than my heart rate monitor for the exertion level. With walking, I honestly do better with very active mintues if I don't log walking anywhere--I just let fitbit track it. I never get very active minutes when walking is manually logged. If logging your power walk on MFP resulted in very active mintues and a higher calorie burn it just means the estimate they use is more generous than the estimate MFP uses. Higher very active minutes is not necessarily more accurate, it is just a higher estimate. I prefer a more conservative estimate. When I log my non-step activities (cycling, weight lifting, yoga, swimming, etc) my fitbit calorie burn seems on the slightly high side of accurate i.e. I need on average around a 4,000 calorie defciit to lose a pound (in theory it should be 3,500). So I guess I would be wary of using a more generous estimate if weight loss is the goal. 

If you are ending up with the correct deficit (and using accurate as possible calorie burn numbers) it is fine. I think it owuld be hard to always be in the calories in/out zone since that is referring to calories burned so far. The calorie burn isn't done until they day is done just before 12am the following day. I guess the thing is whether you are ending up close to the zone. And whether you are getting good results in real life.