How to make sense of Spark cardio activity tracker data?

Cher Tan
Cher Tan Registered Users Posts: 8
Master Explorer
edited January 24 in TomTom Sports
I can't make sense of the following 5 days consecutive days of data.
Mon. 4197 steps 1.37 hr 1943 kcal
Tue. 4308 steps 0.42 hr 1690 kcal
Wed. 6022 steps 1.10 hr 1752 kcal
Thu. 9007 steps 1.42 hr 1850 kcal
Fri. 15023 steps 2.45 hr 1764 kcal

Looks like the kcal burned is not proportionate to the duration hence a ratioed portion of BMR nor is it relative to the steps made. Nor a combination of ratioed BMR and steps.

Please enlighten. Thanks.77449015-13d4-4ee7-921c-3440b7d591fa.png64cb45de-a005-4c68-ab6b-7f12f0179f38.png108e1a34-32b1-48ff-b48e-79f0a6d7d908.png6e081b87-fff0-4fe7-ab0d-bc97a1460bc0.png6e1cb83b-462c-4b7d-8f7c-2c54dabfd7c1.png


  • tfarabaugh
    tfarabaugh Posts: 16,935
    Steps and activity duration are just two of a number of factors that go into the calories burned calculation and it is not a direct calculation (i.e x steps = x calories). The watch computes a BMR based on your gender, height, weight, etc. and takes this along with steps and sports activities to come up with calories burned. So it is taking the base calories from being alive (breathing, digesting, etc.) adding the calories burned during sports activities and then adding calories to reflect active time (including steps). Steps are going to include steps taken during the sports activities so they might not add anything as the associated calories have already been accounted for. This is exactly what it and all other activity trackers are designed to do. In my experience it is generally pretty accurate (or as accurate as BMR based calculations can be as they are based on averages).

    With the exception of Friday the results are fairly consistent, on days with more activity there are more calories and vice versa. It is not a scientific measurement, it is an estimate on a consumer product so you need to take it with a grain of salt. Unless you are living in a lab, calories burned is just a guess no matter how you estimate it. I look at it as a trend item, if my calories are consistent over time and my weight is going up, I am eating too much, if it is down, not enough.

    I hope this helped answer your question. If so, please mark it as a solution so others can look for it if they have the same question.
  • Cher Tan
    Cher Tan Registered Users Posts: 8
    Master Explorer
    Thanks for the answer. It is what I already know but it doesn't explain the inconsistency. If it is just a computation based on data then Friday should not have happened. Right?
  • Cher Tan
    Cher Tan Registered Users Posts: 8
    Master Explorer
    I have probably found an answer. The calories value shown is the estimated TOTAL calories burn on that day. Hence it is the empirical BMR + calories burned based on number of steps (300 for 10,000) steps.

    Friday's data was exceptionally low because the day has not ended at the time of the post. Hence lesser proportion of BMR recorded.

    Thanks for answering to my query.