Is Fitbit Charge 4 overestimating my calorie burn? Makes me nervous eating back exercise calories.
Lib_B
Posts: 446 Member
In September, I decided 20 plus years of abusing my body was enough and started really focusing on health. I definitely need to lose weight, but my approach is more about exercise - 6 days a week and healthy food choices. Going lifestyle change instead of focus on the scale.
That said, I DO track my calories here and I have it set to aggressive weight loss, but I also allow myself to eat back some of my exercise calories without really giving it a thought. I'm not starving myself again. I'm too old for that crap. Some days I may eat 1,200 calories, others 1,500 and even 2,100. The focus ISN'T the scale, but I DO need to lose about 80 lbs and I don't want to completely sabotage what I hope will be a slow, steady loss. My concern is that my fitbit, which is synced to MFP, routinely has my exercise at over 1,000 calories a day.
I do 60 minutes (3-3.5 miles on the treadmill) on M, W, F, S and I lift on T, Tr, S. Doesn't seem to matter the exercise, it's telling me I've burned crazy calories. I know having extra weight will translate into more burn, but this seems really inflated. Thoughts? Do I trust it? Or do I pick a calorie total to just not go over under most circumstances? I know the fitness trackers can be off, but dang, if my burn is more like 400 calories and today it tells me 1,300 calories? Over time, that would amount to a gain. I will say, though, I am also substantially hungrier than I had been previously - like actual hunger, so maybe the burn is legit.
That said, I DO track my calories here and I have it set to aggressive weight loss, but I also allow myself to eat back some of my exercise calories without really giving it a thought. I'm not starving myself again. I'm too old for that crap. Some days I may eat 1,200 calories, others 1,500 and even 2,100. The focus ISN'T the scale, but I DO need to lose about 80 lbs and I don't want to completely sabotage what I hope will be a slow, steady loss. My concern is that my fitbit, which is synced to MFP, routinely has my exercise at over 1,000 calories a day.
I do 60 minutes (3-3.5 miles on the treadmill) on M, W, F, S and I lift on T, Tr, S. Doesn't seem to matter the exercise, it's telling me I've burned crazy calories. I know having extra weight will translate into more burn, but this seems really inflated. Thoughts? Do I trust it? Or do I pick a calorie total to just not go over under most circumstances? I know the fitness trackers can be off, but dang, if my burn is more like 400 calories and today it tells me 1,300 calories? Over time, that would amount to a gain. I will say, though, I am also substantially hungrier than I had been previously - like actual hunger, so maybe the burn is legit.
2
Replies
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How fast have you been losing weight, per week on average since September, eating around that level?
What's your average daily total calorie burn (not just exercise) according to your Fitbit over that time period?
Actual weight loss rate as compared with intake is your best gauge of actual calorie burn.
If you're wearing your Fitbit full time, keep in mind its total calorie burn includes not just exercise but also daily life activity (job, home chores, etc.) on top of the just-being-alive calories. It all counts!
What's your non exercise life like?1 -
How fast have you been losing weight, per week on average since September, eating around that level?
What's your average daily total calorie burn (not just exercise) according to your Fitbit over that time period?
Actual weight loss rate as compared with intake is your best gauge of actual calorie burn.
If you're wearing your Fitbit full time, keep in mind its total calorie burn includes not just exercise but also daily life activity (job, home chores, etc.) on top of the just-being-alive calories. It all counts!
What's your non exercise life like?
Thanks for the reply -
Average daily burn is 2,956 which includes exercise. Average daily exercise reflected on MFP - 900 calories. My weight loss in that time has been about a pound - which is frustrating, but also exactly what I want - no fad diets - just slow and steady. I'm definitely noticing my clothes fitting differently, so I assume I'm putting on muscle at the same time. That said, with 80 lbs to lose, I thought I'd easily be losing one to two pounds a week.
My non-exercise life is a desk job - up to 10 hours a day sitting. Evenings are shuttling kids around to activities, cleaning, cooking, that sort of stuff. I usually sit down around 8 to read and then I'm in bed by 9. Back up at 4:30 and off to the gym.
0 -
Congrats on making changes and finding a plan that's sustainable for you. All that exercise should be great for overall health, and your diet plan sounds sustainable.
Yes, it's probably over-estimating your burn. What does the treadmill say? It's also likely over-estimating btw. A quick Google suggests an hour on the treadmill will be about 500 calories. That difference probably explains why you're losing one pound per week instead of more like you were expecting. That's OK though, that's healthy.
You may be gaining some muscle along the way but it will be hard for various reasons: female, you're older you said although you don't look it from your pic, and you're in a calorie deficit. I'd suggest increasing your protein if you haven't already, to about 0.7g-1g per pound of lean body mass, which will help you retain and build muscle while losing weight.
You mentioned some days you eat more than others. Try to make those days your weights days, and have the lower amounts on your cardio days. Maybe you could increase the intensity on the treadmill a bit, to burn some more? If you've been doing 3-3.5mph for an hour for a while now, you may be fit enough to increase that.
Good luck.2 -
If you want to check the calorie burn for walking/runing specifically, I can recommend this calculator:
https://exrx.net/Calculators/WalkRunMETs
I'm not sure though if your Fitbit is giving gross or net calorie burn for exercise (I have a Garmin myself) so that can skew the comparison.
As for how accurate your Fitbit is overall, you can calculate it yourself, with a bit of effort (presuming your calorie logging is accurate, that can also skew the results):
- add up the calories you consumed over the past 28 days
- add up the calories you burned according to you Fitbit over the past 28 days
- subtract the first number from the second and this is your theoretical calorie deficit. If you divide it by 3500, it'll give you the number of lbs you should have theoretically lost. You can then compare it to how much you actually lost.2 -
Good luck2
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If you want to check the calorie burn for walking/runing specifically, I can recommend this calculator:
https://exrx.net/Calculators/WalkRunMETs
I'm not sure though if your Fitbit is giving gross or net calorie burn for exercise (I have a Garmin myself) so that can skew the comparison.
As for how accurate your Fitbit is overall, you can calculate it yourself, with a bit of effort (presuming your calorie logging is accurate, that can also skew the results):
- add up the calories you consumed over the past 28 days
- add up the calories you burned according to you Fitbit over the past 28 days
- subtract the first number from the second and this is your theoretical calorie deficit. If you divide it by 3500, it'll give you the number of lbs you should have theoretically lost. You can then compare it to how much you actually lost.
That calculator is great. Thank you! I looks like the fitbit MIGHT be close - I do walk at an incline between a 6-10 grade - that puts me at about 800 burned in an hour. I'm definitely going to spend some time this weekend looking at data and then trying to be more analytical about it going forward. I appreciate the tips!1 -
Retroguy2000 wrote: »Congrats on making changes and finding a plan that's sustainable for you. All that exercise should be great for overall health, and your diet plan sounds sustainable.
Yes, it's probably over-estimating your burn. What does the treadmill say? It's also likely over-estimating btw. A quick Google suggests an hour on the treadmill will be about 500 calories. That difference probably explains why you're losing one pound per week instead of more like you were expecting. That's OK though, that's healthy.
You may be gaining some muscle along the way but it will be hard for various reasons: female, you're older you said although you don't look it from your pic, and you're in a calorie deficit. I'd suggest increasing your protein if you haven't already, to about 0.7g-1g per pound of lean body mass, which will help you retain and build muscle while losing weight.
You mentioned some days you eat more than others. Try to make those days your weights days, and have the lower amounts on your cardio days. Maybe you could increase the intensity on the treadmill a bit, to burn some more? If you've been doing 3-3.5mph for an hour for a while now, you may be fit enough to increase that.
Good luck.
Thanks! I'm not THAT old, but I'm definitely in my mid 40's. I appreciate the tips - especially eating more on weight days - I would have thought the opposite, so we'll give that a try. And yes - I do want to increase the intensity. I have a torn ACL in my left knee and a torn ACL graft in my right knee and arthritis that resulted from that surgery. (I have EDS - makes me prone to tears and what not). Anyway, I DO want to run, but I also want to get some weight off before I do that to spare my knees the load... maybe I'll do some intermittent run/walk training - or check out a spin class. Thanks again!2 -
TBH I don't know how fast treadmill speed is. If going faster than you are now means running and that's hard on your knees, my bad. I just have a stationary bike. Perhaps the gym has other lower impact cardio equipment that could increase your calories burned without increasing knee problems?Thanks! I'm not THAT old, but I'm definitely in my mid 40's. I appreciate the tips - especially eating more on weight days - I would have thought the opposite, so we'll give that a try. And yes - I do want to increase the intensity. I have a torn ACL in my left knee and a torn ACL graft in my right knee and arthritis that resulted from that surgery. (I have EDS - makes me prone to tears and what not). Anyway, I DO want to run, but I also want to get some weight off before I do that to spare my knees the load... maybe I'll do some intermittent run/walk training - or check out a spin class. Thanks again!
Re the calories, it's to do with your body being in an anabolic state or catabolic state. Strength training gives you the former, and you should have higher calories around that and for the next 24 hours, to promote muscle growth. Your cardio work and lower calories will put your body in fat burning mode. That can of course include muscle loss, hence increasing your daily protein intake (0.7g-1g per pound lean body mass) and not being in a large deficit on strength training days can help offset that.
For instance, a couple of our take out meal options are extremely high calorie (huge chicken burrito one day, and if I'm being honest too much pizza another day) and I always make sure those coincide with my strength training days, and I might do cardio only on a day with a lighter dinner.0 -
Do you mean you're getting an adjustment from Fitbit of ~1000 calories a day? If so that indicates that Fitbit is reporting your daily calorie burn is much higher than what MFP assumes. And since you are exercising, and MFP's projection is based on no exercise, that may be accurate. Or it may not.
What is your activity level setting in MFP? And how many steps a day do you get on average? If you've put in a low activity level but are fairly active (including exercise) then Fitbit will show a bigger adjustment. If you put in a higher activity level, you'll start with more calories and see a lesser adjustment. Same end result.1 -
To clarify something, just in case, let's say your TDEE is 2300 on strength training days and 2800 on cardio days. To preserve and hopefully build muscle, aim for close to 2300 on the lifting days, and get your big calorie savings on the cardio days.1
-
How fast have you been losing weight, per week on average since September, eating around that level?
What's your average daily total calorie burn (not just exercise) according to your Fitbit over that time period?
Actual weight loss rate as compared with intake is your best gauge of actual calorie burn.
If you're wearing your Fitbit full time, keep in mind its total calorie burn includes not just exercise but also daily life activity (job, home chores, etc.) on top of the just-being-alive calories. It all counts!
What's your non exercise life like?
Thanks for the reply -
Average daily burn is 2,956 which includes exercise. Average daily exercise reflected on MFP - 900 calories. My weight loss in that time has been about a pound - which is frustrating, but also exactly what I want - no fad diets - just slow and steady. I'm definitely noticing my clothes fitting differently, so I assume I'm putting on muscle at the same time. That said, with 80 lbs to lose, I thought I'd easily be losing one to two pounds a week.
My non-exercise life is a desk job - up to 10 hours a day sitting. Evenings are shuttling kids around to activities, cleaning, cooking, that sort of stuff. I usually sit down around 8 to read and then I'm in bed by 9. Back up at 4:30 and off to the gym.
A pound total, or a pound per week?
A pound per week is a decent loss rate, a pound in around a month (you said since September . . . .) requires a little more discussion.
Some considerations or thoughts, that won't gel into actionable advice, just an unpleasantly long essay (sorry):
* Are you logging your calories? If so, add them up for the whole time period, divide by the number of days, because that is a useful piece of information - highly useful, for many of us.
* HOW are you logging your calories, assuming you are: Weighing food? Logging every single thing every single day or skipping now and then? Having some substantially over goal days (special occasions, say) and skipping estimating them because you can't be exact? Avoiding using other people's meal/recipe entries in the MFP food database, seeking out actual USDA entries or others you personally validate? I'm not saying everyone MUST log every calorie, weigh every morsel, etc. . . . but if someone's been approximate and getting XYZ results, that's different in terms of how to analyze the situation than if they're being very detailed. If one wants to be able to do data-oriented analysis, that makes data pretty important. 😆
* If you're new to calorie logging, there's a skill set, and a somewhat subtle one, that any of us has had to develop when we start out calorie counting. If you want more precise data, would like feedback on your logs, then opening your food diary (even temporarily) would let some of the old hands take a look, maybe make suggestions about logging accuracy they've learned the hard way, give you a bit of help in advancing that skill set. Again, not a required thing, but an option if it appeals to you.
* Your activity level in MFP terms (I would think) is likely at least lightly active, possibly even active, given the home chores stuff. If you have your Fitbit synched, the only meaning of that setting is how big your adjustments will be, so a timing issue more than an accuracy one.
* If this exercise routine was new in September, you could still have water retention (for muscle repair) masking fat loss on the scale. That will sort itself out long term as fat loss proceeds, but it can lead to some initial discouragement about perceived loss rate. **
* If you still have monthly hormonal cycles, as is possible in one's 40s, then hormonal water retention can be a similarly confounding thing. Some premenopausal women find that they only see a new weight once a month, at a certain point in their cycle. At other times, water retention ups and downs hide progress. Over time, that sorts out, too (the range of weights bounded by the highest highs, lowest lows, moves downward over the months - fat loss). Perimenopause can be even weirder. Now, that "new low only once a month" thing is unusual, but it's well within the range of possible.
* Confusingly, if one is materially undereating - trying to lose weight too fast (as I'm NOT saying you're doing, because details are unclear) - stress hormones can increase water retention, too. IF that were happening, cutting calories more would be exactly the wrong thing.
* It's possible that your calorie needs are lower than MFP or Fitbit estimates. That's statistically unusual, but possible. If you've only lost a pound in a month, and that weren't the first and only month, we might wonder if you were eating closer to maintenance calories than the estimates would suggest. IF we thought that were true, then cutting calorie intake a bit would be reasonable.
* That you are finding clothes fitting better implies that you're losing fat, and doesn't necessarily rule out added water weight as a factor in the picture (for reasons having to do with the weight distribution of fat/water, loosely).
* Unfortunately, muscle gain in around a month is unlikely to be a major factor. Really good results for muscle mass gain for a woman under ideal conditions would be around a pound a month of new muscle mass. Ideal conditions include a well-designed progressive strength program faithfully performed, good nutrition (especially but not exclusively protein), a calorie SURPLUS (gaining, not losing weight), and relative youth. I'm not saying you won't have gained muscle mass, it's possible you have . . . but it would be very likely to be less than a pound a month.
One note: If a beginner to strength training, we can see pretty fast strength increases, and even appearance improvements pretty quickly. The initial fast strength gains tend to be from neuromuscular adaptation (NMA), basically better recruiting/utilizing existing muscle fibers. Not sure, but I think the appearance improvements are in part from how the retained water fills out some spots.
IMO, most noticeable scale changes within a day or over a few are likely to be water or digestive contents shifts, many days to a small number of weeks and months is when fat changes can show up (in the trends), and muscle mass changes are a thing of many months to years.
I think there's a good chance you're making reasonable progress, and you're just in the potentially-weird getting started phase, still, where the scale misleads.
Best wishes!
** This is a good read:
https://physiqonomics.com/the-weird-and-highly-annoying-world-of-scale-weight-and-fluctuations6 -
How fast have you been losing weight, per week on average since September, eating around that level?
What's your average daily total calorie burn (not just exercise) according to your Fitbit over that time period?
Actual weight loss rate as compared with intake is your best gauge of actual calorie burn.
If you're wearing your Fitbit full time, keep in mind its total calorie burn includes not just exercise but also daily life activity (job, home chores, etc.) on top of the just-being-alive calories. It all counts!
What's your non exercise life like?
Thanks for the reply -
Average daily burn is 2,956 which includes exercise. Average daily exercise reflected on MFP - 900 calories. My weight loss in that time has been about a pound - which is frustrating, but also exactly what I want - no fad diets - just slow and steady. I'm definitely noticing my clothes fitting differently, so I assume I'm putting on muscle at the same time. That said, with 80 lbs to lose, I thought I'd easily be losing one to two pounds a week.
My non-exercise life is a desk job - up to 10 hours a day sitting. Evenings are shuttling kids around to activities, cleaning, cooking, that sort of stuff. I usually sit down around 8 to read and then I'm in bed by 9. Back up at 4:30 and off to the gym.
A pound total, or a pound per week?
A pound per week is a decent loss rate, a pound in around a month (you said since September . . . .) requires a little more discussion.
Some considerations or thoughts, that won't gel into actionable advice, just an unpleasantly long essay (sorry):
* Are you logging your calories? If so, add them up for the whole time period, divide by the number of days, because that is a useful piece of information - highly useful, for many of us.
* HOW are you logging your calories, assuming you are: Weighing food? Logging every single thing every single day or skipping now and then? Having some substantially over goal days (special occasions, say) and skipping estimating them because you can't be exact? Avoiding using other people's meal/recipe entries in the MFP food database, seeking out actual USDA entries or others you personally validate? I'm not saying everyone MUST log every calorie, weigh every morsel, etc. . . . but if someone's been approximate and getting XYZ results, that's different in terms of how to analyze the situation than if they're being very detailed. If one wants to be able to do data-oriented analysis, that makes data pretty important. 😆
* If you're new to calorie logging, there's a skill set, and a somewhat subtle one, that any of us has had to develop when we start out calorie counting. If you want more precise data, would like feedback on your logs, then opening your food diary (even temporarily) would let some of the old hands take a look, maybe make suggestions about logging accuracy they've learned the hard way, give you a bit of help in advancing that skill set. Again, not a required thing, but an option if it appeals to you.
* Your activity level in MFP terms (I would think) is likely at least lightly active, possibly even active, given the home chores stuff. If you have your Fitbit synched, the only meaning of that setting is how big your adjustments will be, so a timing issue more than an accuracy one.
* If this exercise routine was new in September, you could still have water retention (for muscle repair) masking fat loss on the scale. That will sort itself out long term as fat loss proceeds, but it can lead to some initial discouragement about perceived loss rate. **
* If you still have monthly hormonal cycles, as is possible in one's 40s, then hormonal water retention can be a similarly confounding thing. Some premenopausal women find that they only see a new weight once a month, at a certain point in their cycle. At other times, water retention ups and downs hide progress. Over time, that sorts out, too (the range of weights bounded by the highest highs, lowest lows, moves downward over the months - fat loss). Perimenopause can be even weirder. Now, that "new low only once a month" thing is unusual, but it's well within the range of possible.
* Confusingly, if one is materially undereating - trying to lose weight too fast (as I'm NOT saying you're doing, because details are unclear) - stress hormones can increase water retention, too. IF that were happening, cutting calories more would be exactly the wrong thing.
* It's possible that your calorie needs are lower than MFP or Fitbit estimates. That's statistically unusual, but possible. If you've only lost a pound in a month, and that weren't the first and only month, we might wonder if you were eating closer to maintenance calories than the estimates would suggest. IF we thought that were true, then cutting calorie intake a bit would be reasonable.
* That you are finding clothes fitting better implies that you're losing fat, and doesn't necessarily rule out added water weight as a factor in the picture (for reasons having to do with the weight distribution of fat/water, loosely).
* Unfortunately, muscle gain in around a month is unlikely to be a major factor. Really good results for muscle mass gain for a woman under ideal conditions would be around a pound a month of new muscle mass. Ideal conditions include a well-designed progressive strength program faithfully performed, good nutrition (especially but not exclusively protein), a calorie SURPLUS (gaining, not losing weight), and relative youth. I'm not saying you won't have gained muscle mass, it's possible you have . . . but it would be very likely to be less than a pound a month.
One note: If a beginner to strength training, we can see pretty fast strength increases, and even appearance improvements pretty quickly. The initial fast strength gains tend to be from neuromuscular adaptation (NMA), basically better recruiting/utilizing existing muscle fibers. Not sure, but I think the appearance improvements are in part from how the retained water fills out some spots.
IMO, most noticeable scale changes within a day or over a few are likely to be water or digestive contents shifts, many days to a small number of weeks and months is when fat changes can show up (in the trends), and muscle mass changes are a thing of many months to years.
I think there's a good chance you're making reasonable progress, and you're just in the potentially-weird getting started phase, still, where the scale misleads.
Best wishes!
** This is a good read:
https://physiqonomics.com/the-weird-and-highly-annoying-world-of-scale-weight-and-fluctuations
I actually think I figured it out. My fitbit was reading my heartrate a LOT higher than it is - basically had me doing cardio several hours a day - which would explain the really high exercise calorie reading and probably why my scale isn't moving. I've reset it to *hopefully* resolve the issue. In the meantime, I'm settling on 1500 -1600 calories a day until I'm confident the tracker is accurately tracking. (my tdee minus 750)2
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