How accurate is the Fitbit 2?

Does any one know how accurate the Fitbit 2 is in giving calorie burn over a 24 hour period. Especially, accuracy while brisk walking. Can it be relied on to provide a true calorie deficit after subtracting caloric intake? I wear it 24 hours minus shower time.

Replies

  • MegaMooseEsq
    MegaMooseEsq Posts: 3,118 Member
    edited March 2018
    My personal experience was that the Fitbit 2 was reasonably accurate for estimating calorie burn while walking as well as jogging. It's not perfect, because nothing is, but watching my results over time, I was happy with the numbers I got. You can always compare your calories per minute with the formula .03 x wt in lbs, or calories per mile with .57 x wt in lbs. I got the formulas from Runner's World but I'm pretty sure they've been around a while and are considered fairly accurate.
  • janejellyroll
    janejellyroll Posts: 25,763 Member
    I have the Charge HR 2 and I've found it to be a very accurate source for calorie burn estimates for walking and running.
  • af240
    af240 Posts: 37 Member
    I have the alta HR and have felt that it's fairly accurate giving me my BMR calorie burn and regular increased activity, but gives way too many calories for walks/run it automatically detects. Especially now after reading the article MegMoose posted.

    Everyday during my lunch hour I walk up and down our parking garage. It's about 5 levels and I walk at a very brisk pace and it's an incline so I definitely increase my HR a small bit, but I never get winded or anything. For a 60 min walk (I don't know how many miles it is, but based off the steps I'd say it's around 3 miles), fitbit says I burn somewhere between 5-6 cals/minute and gives me around 300-350 calories burned total. That always seemed like a lot considering I'm only 5'2 and 125lbs. Using the formula from the article, 3.75 cals/minute does sound more reasonable for a walk, maybe closer to 4 considering the incline.

    I sync my fitbit to MFP and I try to stay 100-200 cals below the extra cals it gives me for my fitbit activity for this reason.
  • cwolfman13
    cwolfman13 Posts: 41,865 Member
    I have a charge 2 and my calorie expenditure is pretty much in line with my own data. I manually input exercise into the Fitbit app though, as it overestimates my cycling and whatnot.
  • malibu927
    malibu927 Posts: 17,562 Member
    Flex 2 or Charge 2? Since the Charge has the heart rate sensor there could be an even greater difference between the two.

    That said, I had the first generation model in both of them and found them fairly accurate.
  • davidrip1
    davidrip1 Posts: 70 Member
    Sorry. Charge 2.
  • davidrip1
    davidrip1 Posts: 70 Member
    Does your Fitbit match your 1 pound weight loss with a 3,500, 24 hour, calorie deficit over an extended period?
  • Nony_Mouse
    Nony_Mouse Posts: 5,646 Member
    davidrip1 wrote: »
    Does your Fitbit match your 1 pound weight loss with a 3,500, 24 hour, calorie deficit over an extended period?

    Mine does, yes. Ridiculously accurate for me.