Apple: Relax, fanbois! We never meant to read your heart rate during wild wrist action Apple – having tweaked how its Watch monitors a customer's heart rate – has been forced to explain the change, after fitness freaks freaked out about the gizmo's irregular tracking function. On Saturday, in an update on its support page, the iThing maker explained that Apple's wristjob "attempts to measure your heart rate …
Well I guess when you're the only child of a guy worth $30+ billion, buying a pair of gold Apple Watches for your dog is like you or I buying the dog a collar from the discount bin at Petco.
This is exactly the sort of thing that caused a revolution in France a couple centuries ago, China's ruling class better tell their billionaires to "watch" out!
When exercising, you use the workout app.
When at rest, the watch records your resting heart rate (which is a health function rather than a fitness function).
The watch also monitors how much you have exerted yourself during the day. You can set target for movement which is monitored in terms of calorie burn. The calorie burn calculations use heart rate data and regardless of whether you have used the workout app or not, a record of exercise gets added to your exercise record for the day, whenever you have an elevated heart rate. The heart rate measurements are taken less frequently when not in the workout app.
Yesterday I went for a cycle ride on a course I cycle often. I started the workout app and paused the workout part way through when I was waiting to meet a co-rider, but after we met, I forgot to unpause the app. It was a good daily session (about 45k), so I was annoyed when I realised I had failed to resume the workout app, assuming the exercise session would have failed to register against my daily target. When I checked the exercise app, the recorded calorie output was, as I expected, far lower than it should have been (about 550 calories when normally over that course it would have been about 1500+). However when I checked my daily exercise record, I was pleased to see my energy output had been recorded (so I still exceeded my daily target). Over 1200 calories had been added to my tracked exercise for the day. So this confirms the watch tracks exercise even when not in the workout app. However I noticed the amount added was about 20% less than it would normally have been if I had used the exercise app throughout the course.
So, to me it is clear the behaviour of the watch is:
1. Any elevated heart rate is tracked as exercise and added to your exercise record. If you are not specifically in the workout app, the sampling rate is clearly lower. It may take a while before the watch registers that you have an elevated heart rate. And once it decides you are exercising, my guess is that it does so less accurately (with a lower sample rate) than if you specifically start the workout app. It makes a record of your energy output for exercise tracking and checking if you are meeting daily targets (if you want that function), but, though it checks your heart rate every now and then, doesn't keep a record of your heart rate when it is elevated.
2. Switch on the exercise app and the tracking of energy output is more accurate and done with a higher sample rate for your heart rate. Plus it keeps a record of your heart-rate throughout.
4. When not in the exercise app, though the watch checks your heart rate, it only takes a record of your resting heart rate. I presume this behaviour is deliberate and is a health monitoring function (e.g. specifically not an exercise record). Resting heart rate is a significant health metric. Lower resting heart rate indicates a higher general fitness.
"Apple's update to the Watch software had alarmed some folk, who suddenly spotted that fewer records of their heart rate were being stored on the device.
Some fanbois suggested that Apple was grappling with a bug. Not so, apparently.
Yup, it's a feature, not a bug ..."
Non-pathological vendor approach: update has new feature; is explained in update release notes; perhaps even include a settings option which can change the default, albeit defaulted to the new behaviour.
PS @Mephistro, I agree that this may be to protect privacy during "private moments" (I can't see any other reason, surely if you really want to measure your pulse 24x7 you don't want to only measure it at rest. But I'm stunned at your suggestion that revealing such moments could be "the cause of lots of divorces?" Seriously?
After all, a watch that fails after 18 hours is really a bracelet isn't it?
I don't get why would you only want your heart rate when inactive: what's the point?
As an aside I spotted my first couple on the tube wearing real watches on their left wrists and Apple Watches on their right wrists, and it looked just as stupid as you'd imagine it would.
Without that particular feature the wrist action of the title is unlikely to happen, no?
Regarding the above "fail at science" comment: it was an error made while typing in haste. Of course it is the Y chromosome that induces male characteristics. Still, it's a mistake anyone could make - X is the one with the extra leg, after all.
If you want to use heart rate measurement to assess health on an ongoing basis you need to record it on an ongoing basis.
Taking a sample every 10 minutes if you are not moving is only going to give you a low point and will tell you nothing about the stresses placed on you during the day so if you spend most of the day stomping round the office screaming at minions you will have no idea of the stress impact on heart rate.
I suspect the update is purely a battery saving tactic and the consideration that it will skew downwards any of the resting energy expenditure or give an insight into the impacts of stress has been ignored.
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