What's more accurate? Calculating TDEE or Fitbit numbers
Options
kar328
Posts: 4,148 Member
I just hit the 30 lb loss mark so I"m trying to update numbers. Last week I got a Fitbit Flex, wore it continuously. It gives you the calories you burned in each 24 hour period. Mine ranged from 1965 - 2188 with the seven day average being 2072. A 20% deficit would put my TDEE at 1658.
I also just tried the formula Sara has in the Setting Your Calorie and Macro Targets. I currently do not eat back exercise calories and log them here as 1 calorie. My Fitbit account is synced with MFP so the exercise calories read the same for both. I did 30 days and a 7 lb loss and my TDEE comes out to 2356 with the 20% deficit at 1885.
There's a 227 calorie difference between the two. I realize it's not a huge difference and I'm happy with the weight loss progression, but I'm still really curious as to opinion on what would be more accurate. Thanks
I also just tried the formula Sara has in the Setting Your Calorie and Macro Targets. I currently do not eat back exercise calories and log them here as 1 calorie. My Fitbit account is synced with MFP so the exercise calories read the same for both. I did 30 days and a 7 lb loss and my TDEE comes out to 2356 with the 20% deficit at 1885.
There's a 227 calorie difference between the two. I realize it's not a huge difference and I'm happy with the weight loss progression, but I'm still really curious as to opinion on what would be more accurate. Thanks
0
Replies
-
Also interested in the reply. I have a Fitbit One and my totals are always lower than expected.0
-
I just hit the 30 lb loss mark so I"m trying to update numbers. Last week I got a Fitbit Flex, wore it continuously. It gives you the calories you burned in each 24 hour period. Mine ranged from 1965 - 2188 with the seven day average being 2072. A 20% deficit would put my TDEE at 1658.
I also just tried the formula Sara has in the Setting Your Calorie and Macro Targets. I currently do not eat back exercise calories and log them here as 1 calorie. My Fitbit account is synced with MFP so the exercise calories read the same for both. I did 30 days and a 7 lb loss and my TDEE comes out to 2356 with the 20% deficit at 1885.
There's a 227 calorie difference between the two. I realize it's not a huge difference and I'm happy with the weight loss progression, but I'm still really curious as to opinion on what would be more accurate. Thanks
Both of these methods are estimates and neither one will be more accurate than actual data that considers your intake and your change in weight.
If you're asking from an application standpoint, I would continue using the intake you are using that has brought you your current progress.
If you're asking from a general knowledge standpoint, I would expect an HRM properly configured to potentially be more accurate. (Doesn't make them necessary however, as many people, myself included, can create a pretty accurate caloric deficit without one, by starting with an equation and adjusting based on results).
Finally, 227 calories IS a significant difference, but don't let that change your plan or your methods, especially if you're getting results that you believe are sustainable.0 -
Thanks for posting this, I was wondering the same thing!
After 10 days with my Flex, I'm burning more than I thought I was. It helped me realize I'm probably more a "moderate" level than "light" for the calculators. However, what it says I burned for the past week or so is also about 200 or so above my results for the past 6, using the history calculation... but it's hard to compare a relatively small set of data. I've been averaging under the macro recommendations, so this info was helpful in the mental hurdle of bumping those up- even with a margin of error, it helps me realize I'm burning more that needs to be fueled.
Wondering if after I have some more data, history data and Fitbit info will start to come more in line - we should check back in a month or two!0 -
Thanks for the feedback. You can't see your HR on the Fitbit, I do have a Polar and should probably try it for a 24 hour period on both an exercise and non-exercise day and see how that turns out.
I've been keeping with what I've been doing. I'm happy with the 1.5 lb/week loss that I'm averaging. I'm still a work in progress when it comes to consistent exercise on a weekly basis. The Fitbit is good for helping me try to get in more steps even if I'm not actively doing a workout.
I will say I'm kind of enjoying playing with the numbers and seeing how this all works. This group is very educational and I appreciate the efforts that get it that way.
:flowerforyou:0 -
Just to add a little color, these types of devices use algorithms based on samples to derive estimates and individual factors may not fit into those, especially for people with metabolisms outside the 'normal' range such as those with thyroid issues or PCOS.
Both have their pros and cons.
For example. HRMs are not accurate at all for anything other than cardio, so wearing it for 24 hours would not yield any meaningful information. On the flip side, HRMs are more accurate for cardio than fitbits and similar devices.
When compared to actual results, there will be some variances due to water weight fluctuations, but this is by far the best method imo, assuming a relatively consistent activity level. If you do variable amounts of cardio each week, especially endurance amounts, then consideration for this needs to be accounted for.0 -
My personal experience has been that neither the online calculators nor the fitbit have gotten close to what experience shows me I need to eat. That said, the fitbit gets closer, but what it thinks is maintenance for me is definitely a deficit, even allowing for the fact I might over-estimate calories in at times. I mainly use the fitbit to count steps as it is a very smart and subtle pedometer compared to most.0
-
Locking so we can keep track of active threads. If you wish for the thread to be unlocked should you have further questions, please feel free to PM either myself or SideSteel, including a link to this thread and we will unlock it so you can.0
This discussion has been closed.