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Calories Burned Disrepancy

Took ownership of my 235 yesterday and really impressed so far. I just went for a 5k run and the recorded calories are 287. This seems low compared to my old tracker (Fitbit would record about 480). When I input the distance, time and my weight into a calculator on Runner's World it comes up with 395 calories. Strava (which I have just swapped to, from Endomondo) is saying 600. From some research just now I have decided to ignore Strava as it seems to over calculate. I don't want to get hung up on exact calories burnt, but I'm a bit of a sucker for stats, and 287 seems very low given I was not far off max heart rate. I've checked that I've entered my weight correctly. Is this a common issue? Is there anything I can do about it?

Thanks!
  • That does seem low. I will usually burn 400ish for that distance (46 yrs, 195 lbs). You mentioned you entered your weight correctly ... doesn't age matter too? In any case, I would give a few more runs to see if a 'low' pattern continues. This may have just been a 'getting to know you' run. One run does not make a pattern enough to draw conclusions.

    Max
  • It can take quite a few runs for the watch to "learn" about you so that number could well change in the future.

    What kind of effort was it? Just a reg run or more of a tempo style run? What was the training effect?

    FWIW, I'm 65kg and for runs with a TE of around 3 I burn 50-55 calories per km.
  • 6600 entrance

    Thank you. How do I find my training effort please? I'm relatively new to running and only go once a week. I also do HIIT and weights tho so am pretty fit. I'd say I was putting in 80-90% effort.
  • Found it. TE was 4.8.

    Also, can anyone tell me where I can find my recovery heart rate please? Still getting used to all the menus! Thanks so much.
  • Recovery heart rate is not saved anywhere as far as I know. To view it, pause your activity and wait 2 minutes, after which you can resume/save your run.

    Max
  • A few notes about the calorie calculation and related statistics.

    1) First, your calorie calculation is also reliant on your estimated VO2 Max. The higher your capacity for taking in Oxygen the lower your heart rate will be at a particular exertion level and the lower your calorie estimate will be. Your 5K result really isn't that far out of line from what I've seen. Due to foot problems at present I cannot do any running but I do get in some speed walking when the weather and my right foot are up to it. Last August when my foot was in much better condition at a 13:30 minute per mile pace my average calorie count per mile was 72. At that time my VO2 Max was at 38 and the average heart rate would be around 140-144 bpm, about 90% of max.

    However, I have had one occasion where I did a 3 mile (5K) "run" on an Elliptical Trainer with a 150 bpm average heart rate and the 235 listed the total calories for that event at 103. I contacted Garmin about that obvious error and all they would do was claim that the heart rate trace looked a bit "off". BTW, direct overlays of that trace over other runs with a more normal calorie estimate showed heart rate traces that were basically a match. So, sometimes the 235 will get it's "math" totally wrong.

    2) Your VO2 Max estimate is pretty critical for nearly every fitness statistic provided by the 235 and the software from Firstbeat Technologies that Garmin uses for this calculation is IMO a bit too limited. First, Firstbeat ONLY uses or provides a Running VO2 Max and that running activity must be done on level ground at a steady pace AND the heart rate must remain stable during that run. If you do any running on hills, grass, gravel, or sand your VO2 Max estimate will be incorrect. If you use ANY indoor exercise equipment such as a Treadmill, Stationary Bike, or Elliptical Trainer your VO2 Max will be incorrect. I also suspect that if your age is outside the range of 20 to 45 your VO2 Max will be incorrect. Quite simply, if you don't satisfy the criteria for Firstbeat's software very closely you can only view any of the provided statistics such as VO2 Max, Recovery Time, and Calories as Suspect.

    In my case being 62 years of age and nearly totally reliant on using an Elliptical for "roadwork" has resulted in my VO2 max being listed at 33 at present in spite of the Shape Sense online calculator providing an estimate of 41-42 for my most recent workouts. As a result anytime I work hard enough to actually provide some improvement I will typically finish my workout with the Recovery Advisor claiming I need to rest for 72 hours. To be blunt for me Firstbeat Technologies software is basically JUNK SCIENCE and these statistics are 100% USELESS for me. And yes, I am a bit resentful that Garmin hasn't woken up to the fact that a rather large segment of their user base is actually Baby Boomers, not exclusively Millennials.

    3) The Step Counter in the 235 is rather poor. One problem is that if your arm motion is restricted for any reason your step counter will be reduced. For example do a mile on a treadmill with your hands on the contacts for the heart rate monitor on the machine and you will find nearly zero steps recorded. The second problem is that the step counter is actually quite easy to "spoof", imitate the motion for shaking a bottle and you will see your "steps" being added to at a rate equal to your arm motion. Third, the Heart Rate Estimate is largely based on your Cadence. So, if your arm motion isn't compliant with your actual pace you'll see some distinctly strange heart rates listed. For example I can shake my arm quickly to mix a Martini or a Protein drink and my reported heart rate will shoot up to 175 bpm. BTW, I've only seen 2 occasions when my heart rate actually hit 170 as measured with a chest monitor and on both occasions it took over 40 minutes of work to get there and I was dripping with sweat, so shaking a protein drink really doesn't shoot my heart rate to the moon like the 235 has estimated at times.

    BTW, I started with the Forerunner 15 and still use one in parallel with my 235 at times. Doing this has revealed just how poor the step counter in the 235 is. Because in the much older 15 you just cannot "spoof" the step counter but you can use the heart rate contacts on a treadmill and get an accurate step count. The reason for this is the 235 only uses one axis of motion where the older 15, and the Fitbits, use at least 3 axis' of motion. You can even put a 15 in a shirt pocket and get a good reliable step count due to the combination of a front to back surge in combination to a vertical and side to side motion of your body. Recently after shoveling snow for 4 hours, the 235 showed 581 steps for that period while the 15 in my shirt pocket showed 6500 steps.

    Note, the wrist monitor does NOT operate 100% of the time and when it's not operating it estimates your heart rate based on your "activity" level and what your Recovery Advisor is reporting. After my typical Saturday max intensity workout if I take off my chest monitor too soon my heart rate indicated for simply walking slowly to the fridge to get some Gatorade will be reported as spiking to 130-140 bpm, because when the Recovery Advisor is reporting 72 hours that heart rate estimate will be consistently 30-50 points high for ANY activity recorded by the step counter. Calorie count during this recovery period will also be way high. BTW, knowing this defect has me now keeping my chest monitor on and the watch running in the Bike Indoor mode for about 4 hours after my Saturday workouts so the 235 is "forced" to use the chest monitor and give me much more honest calorie estimates..