Garmin Calories Estimate Per Day

Hello!

I started tracking my food etc at the beginning of the month to clean up my diet a bit. It would be nice to lose up to 15 pounds, but I am at a healthy weight and would be okay with recomposition instead. I’m mostly looking to better establish healthy eating patterns.

I wear a Garmin 235 which does all day heart rate. While I got it initially for running, I wear my watch almost all the time and noticed it estimates calories burned all day based on my heart rate. I’m wondering if others have found that to be accurate. I do crossfit which is very hard to track in terms of calorie burn, so if this all day reading is a good estimate of what I’m actually burning by living and breathing, then I would like to use it as my guide for my goals.

Right now my MFP goal is set to lose 0.5lb a week. I just went back and added up all the calories my Garmin said I burned over 13 days and compared it to what I ate during those same days and it ended up being that I had an overall deficit of about 2200 calories (or about 0.6 lb). Looking at my weight change over two weeks, I would say that’s pretty likely, though we all know how weight fluctuates!

Do others compare their Garmin calories to MFP? Is it an accurate picture of what your body really does burn throughout the day?

Replies

  • Psychgrrl
    Psychgrrl Posts: 3,177 Member
    For weight loss and maintenance, I find the daily burn/steps calories to be overestimated, but the logged exercise to be pretty accurate, regardless of type. I have a Vivoactive 2–about two years of data.

    I use weight * .31 * miles for daily steps burn. Usually 200-300 calories instead of the 1000 Garmin gives me.
  • asochable
    asochable Posts: 43 Member
    Interesting! It makes sense that the calories for exercise would be more accurate. Thanks for sharing your method!
  • NorthCascades
    NorthCascades Posts: 10,970 Member
    Mine is too generous with walking calories. It would be over for cycling by as much as 40% if I didn't use a power meter. I think it's under for Nordic skiing.
  • AnnPT77
    AnnPT77 Posts: 31,717 Member
    My Garmin Vivoactive 3 significantly underestimates my all-day calorie burn (by about the same proportion that MFP and some of the TDEE calculators do). It's off by a few hundred calories.

    I have limited evidence for the exercise calorie burn's accuracy, but slightly suspect it underestimates that a bit, as well, comparing it with my Concept 2 rowing machine, which has a reputation for reasonable power estimates, thus reasonable calorie estimates. I use the exercise estimates when I don't have a more believable source. (For weight training, I think MFP's database is likely more believable, though I haven't crossed checked the Garmin enough times to be sure: Since it knows I'm weight training, they could shift from heart rate to METS estimating algorithms or something, but I don't know whether they do.

    It's all estimates from any of these fitness tracker/HRM devices: If you're near the mean(s) for whatver research statistics they used in developing their estimation algorithms, and their algorithms are sound, the device will probably give a fairly close estimate. If you're not near the mean(s), or their algorithms are not so hot, it will likely be further from reality.

    Either way, experience over time will tell you the answer. So, keep doing the weight vs. calorie intake calculations for a while, and you'll see where you come out.
  • Grnhouse
    Grnhouse Posts: 254 Member
    Are any of them 100% accurate?
  • AnnPT77
    AnnPT77 Posts: 31,717 Member
    Grnhouse wrote: »
    Are any of them 100% accurate?

    No. They all estimate calories. There's no affordable, portable way to measure calorie burn.

    For the majority of people, the good-quality ones (Polar, Garmin, etc.) are likely to be close enough to be useful. For those farther off based on experience, there may be some adjustment strategy (like, say subtracting 10% or adding 15%) that comes close, but it will be more fuss to figure that out initially.

    I think I could do that (since my Garmin underestimates) but have no reason to do it, so haven't bothered: In a year of weight loss, and nearly 3 of maintenance, during most of which I've been logging on MFP, I have enough data to make a pretty good estimate of my NEAT or TDEE, based on intake and bodyweight changes, and set my calorie intake accordingly. I know some things about myself, like my NEAT is lower in Winter than Summer (more of my sedentary hobbies when it's cold outside, etc.). It works fine. I'm maintaining as expected.

    I've only had the Garmin Vivoactive 3 since sometime last Fall, when I had to replace older devices (a HRM and non-HR GPS pace/distance thingie I use for rowing and such). It works great for what I most want and need it for: heart rate for monitoring workouts; pace & distance for rowing; speed and distance for cycling/walking; etc.

    I've been using electronics for years now to guide workouts; it was kind of strange to me to come to MFP and find so large a percentage of people kind of laser-focused on the calorie estimates. ;)
  • azzeazsaleh5429
    azzeazsaleh5429 Posts: 77 Member
    My forerunner 35 doesnt do calorie adjustment anymore. I walk over 15k steps 4 times a week. I just dont consider it in my daily so its an added bonus
  • jenniday1229
    jenniday1229 Posts: 27 Member
    asochable wrote: »
    Hello!

    I do crossfit which is very hard to track in terms of calorie burn, so if this all day reading is a good estimate of what I’m actually burning by living and breathing, then I would like to use it as my guide for my goals.

    I do Crossfit 4x week and ended up moving from "Sedentary" (I work a desk job) to "Lightly Active" in MFP for this very reason. I don't add separate exercise anymore at all. It's actually worked great and I'm still losing an average of 1lb/wk which is my goal.