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I use a TICRX HRM paired with the Polar App when I run or use my elliptical. I also wear my Apple Watch. When I do a 10 minute Elliptical the Apple Watch may give me 60-70 active calories burned and the Polar App using the HRM will show 110-120. The Elliptical Machine will show like 180, lol. I use the Polar APP measurement and take about 10% off. I Have found the HRM with the Polar App to be spot on with the Hear Rate to net calories burned formula.

When I run the Apple Watch is much closer to the TICRX HRM than the elliptical measurement. I don't know why but it just is.
Does the elliptical ask for (and do you enter) your sex, age, height, and weight at the beginning of the workout? And, does it capture HR throughout the workout? If not, then its calorie algorithm is mostly a guess. If it is gathering all of these metrics, then it should be close to the other tools (unless it has a very crappy algorithm).
 
The elliptical only asks for Weight and Sex but not age or height. It is an educated guess.
 
That probably explains some of it. There is a material calorie burn difference based on age. And, height may also play a significant factor, as leg length would affect body movement dynamics. The elliptical may be based on an older or simpler calorie algorithm.
 
BTW, today I updated my AppleWatch to the latest 2.2 beta released today or yesterday. Now the active calories from my elliptical workout are back up to the 450 - 475 range. The previous version had them at around 250 per 45 minute workout, so something was adjusted in this new beta or the process of installing it fixed the problem.
 
BTW, today I updated my AppleWatch to the latest 2.2 beta released today or yesterday. Now the active calories from my elliptical workout are back up to the 450 - 475 range. The previous version had them at around 250 per 45 minute workout, so something was adjusted in this new beta or the process of installing it fixed the problem.
Cool, do you mind doing a dorky calculation on your workouts?

Can you pull the active and total calories, subtract to get BMR calories, divide the BMR calories by the minutes of the workout, and then multiply the BMR calories per minute to get the BMR calories per day?

On mine with OS2, my daily summary has my BMR at about 1,900 calories/day. However, when I look at the BMR calories during a workout, it is around 2,800 calories/day. So, with OS2, it looks like the AW and phone Activity app are doing some manipulative machinations to optically correct BMR, but it may be boggered across the active calorie algorithms. I am curious if they fixed all of it with 2.2.
 
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