Confusion with calories burnt

[7Anita7]

I have bought my versa 2 days ago and I am now giving it a try. What confuses me is the calories count. Today morning I had a 30 min walk and all other online calculators (I have checked quite a few) indicated I burned around 100 kcal. However my versa claims it was 189. The difference is obviously very significant.

Is it because apart from the ‘active’ calories versa also provided the ‘resting’ calories for that 30 min? Or is the watch simply faulty altogether?

I purchased the watch mainly to lose weight and I fear now that it was money thrown out of the window.

In case the watch is overestimating my calories bunt, is there a way of ‘adjusting it’ by, say, lowering my weight by a certain %, etc.?

I will be grateful for any reply.

[SteveH]

It might be the "resting" calories that are causing the confusion. These are known as your BMR calories, and are the calories you burn just keeping your body alive (even when asleep). They are calculated from your profile settings for age, height, weight etc so you needn't be wearing your fitbit to get them. What you are seeing on your fitbit includes the total BMR calories burned since midnight.

Fitbit has a few more details in this help file: Help article: How does Fitbit estimate how many calories I've burned?

The thing that trips most people up is quite how many BMR calories we burn. I burn around 2000 calories per day in total and 1400 of those are my BMR calories.

Fitbit usually does a good job in calculating them but there are BMR calculators available if you'd like to check yours. They can't be manually adjusted but, as you say, you can alter the calculations by changing your age, weight, height etc in your profile. I wouldn't rush into that though in case the calculations fitbit make are correct.

If you do decide you want to change the calculation then use one of the online BMR calculators to adjust your settings until you get the numbers you want and then make those changes in your fitbit profile. This will be a lot easier than trial and error in your fitbit profile.

[7Anita7]

Hello Steve

thank you for your reply. I have checked my BMR and it looks ok, in fact it’s even lower (1225) when compared to other calculators (1385, Harris Benedict method). However even if I discount the BMR calories for that 30 min walk, which is around 26 calories, I am left with ‘active’ calories of 163 as opposed to 100, as per other calculators.

Is there anything else you suggest I could do?

[SteveH]

FYI I think fitbit use the mifflin st jeor method in its calculations.

I'm not sure what to suggest. Do your steps / distance look reasonable for your walk? I'm wondering if the calorie calculation could be off if the steps are not correct.

[7Anita7]

I think so but I will look into it on the way back the same way later today. 🙂
Last question, if that’s ok: do you recommend connecting Fitbit to my fitness pal or given the potential inaccuracies its best to keep them separate?
Apologies for bothering!

Sent from my iPhone

[SteveH]

Please don't apologise, I'm happy to help if I can and I can't then there's plenty in the community who can.

I've been using MyFitnessPal since I started with fitbit over 5 years ago. What works for me is to strictly use just MyFitnessPal to log my food and strictly just fitbit to track my activity. I did this as the fitbit food database just didn't work out for me. I've found the automatic link between the two works well but there is more scope for confusion / issues if you log food and / or activity in both.

[7Anita7]

Ah, That’s how I felt about linking them too. Thank you and have a nice day. 🙂

Sent from my iPhone

[kaelarenee7]

The versa is also taking into account your heartrate during your walk, which will affect how many calories were burned whereas online calculators don't do that.

[SunsetRunner]

It’s possible Fitbit is overestimating calories. Just a few days ago I was using my gas powered weed eater and it registered as 26 minutes of bicycling and supposedly burned 155 calories. Majority of the calories Fitbit says I burned came from the vibration of the weed eater even though I wasn’t moving much. Something you have to consider is those calculators are just estimates. They don’t take into account your individual muscle mass or other factors which would affect how many calories you burn. Fitbit is a little more tailored to you individually but again, doesn’t account for your individual muscle mass. If you find you are not losing any fat or are gaining fat after a while, drop your calories a little more.

[Dominique]

If weight loss is one of your main goals, I would suggest you focus on your total daily energy expenditure (TDEE, i.e. calories burned over 24 hours), as opposed to calories burned during any given bout of activity (e.g. the 30 minute walk you mentioned). This is because whatever formal activity you do during 30-60 minute only has a small impact on your TDEE. And like @SunsetRunner noted, it is important to realize calories burned as reported by your Fitbit are an estimate. Go by that estimate, assume it’s more likely than not it will be on the high side, monitor your weight over time and make adjustments (to your activity level and your dietary intake) if needed.

[DrScully]

Came to say the same thing. Calroies burned increase with elevated hr.