Apple Watch & Fitness: watchOS 2 Fixes Some Issues, but Heart Rate Still Inconsistent

I’ve written a lot about the Apple Watch, especially about the problems using the device as a fitness tracker. Its resting calories calculation was grossly exaggerated, the heart rate sensor recorded ludicrous numbers, and the device was stingy in recording exercise minutes.

watchOS 2 will be released next week, but I’ve already install the GM (gold master) on my Apple Watch. I’ve found that, while the new software fixes some of these issues, there are still some glitches.

ExerciseFirst, exercise minutes. Previously, my Apple Watch hardly recorded any minutes, no matter what I did. My only exercise is walking, and I walk fairly briskly, generally around 12 min/km. That should be enough to count as exercise; my Fitbit One counts that time as “active minutes.”

With watchOS 2, my Apple Watch records my exercise much better. If I set a workout, either an indoor walk on my treadmill, or an outdoor walk, almost all of the time is counted. If not, some of my walking is counted, but not all.

CaloriesAs for resting calories, they no longer exist. Instead of showing Active Calories, Resting Calories, and Total Calories, the Activity app only displays Active Calories and Total Calories. (And, to confuse things, the Health app calls these Active Energy and Resting Energy.)

It’s true that showing the Resting Calories isn’t very useful; you can do the math if you want. The Total Calories I’ve seen so far seem to show that the resting calorie calculation is much more accurate. (Note that, in the example to the left, I only installed the software around 10 am yesterday, so it doesn’t display a full day’s calories; it didn’t pick up my resting calories before that time.)It’s worth noting that watchOS 2 seems to be calculating active calories differently. Here’s my activity on Tuesday. I walked about 8,000 steps, and I burned, according to the Activity app, 915 active calories. You can see that only 15 minutes was counted as exercise, even though I was walking at the same pace as I usually do.


In this screenshot that I took before updating the Apple Watch, you can see the different breakdown of calories.


So, for roughly the same amount of steps on Tuesday (8,064) and yesterday (8,368), the Apple Watch credited me with 915 calories on Tuesday, compared to 626 calories yesterday. Granted, yesterday had a bit less activity – that prior to 10 am – but since I was asleep most of the time, it would be negligible.

Next we come to the heart rate sensor. When using a workout – indoor walk or outdoor walk – the heart rate sensor checks continuously. One problem with watchOS 1 was that the numbers it returned were often way too high. I’d see my heart rate recorded at around 160, when it was, in fact, between 100 and 120. Alas, this is still the case. Here’s an example of heart rate data during a walk:

Heart rate

You can see that, as it was being recorded every ten seconds, it jumped from 116 to 162 suddenly. I saw something similar in a walk I took this morning. It recorded my heart rate around 161-162, dropped at one point to 98, and then went back up, only to drop back down to the high 90s again (I was walking a bit slower than my usual pace).

Heart rate2

So, it took Apple four months to make the Apple Watch a somewhat reliable fitness tracker, but the heart rate monitor is still broken. I doubt this is a hardware issue with my watch; I already exchanged the first one I got, before Apple admitted that it was a software issue. I am truly amazed at the problems with this part of the Apple Watch, given that it was one of the main selling points of the device. Apple certainly should do better, and get this to work correctly.