Heart rate unreliable

Just wanted to add to my frustration over the heart rate monitor. My hear rate data for my workout today was all over the place (when it even read a heart rate). I've used both Polar and Wahoo hear rate monitors for years, and I was hoping, based on the exercise lab Apple set up and all the testing they have been doing over the last two years, that it would work. Watch is on correctly, etc.

Apparently, you can pair watch with a bluetooth chest strap, and I guess I'll try to connect my Wahoo to watch so I can get accurate readouts.

Sport Model 42mm

Just remember that HR tracking on a watch will not be as accurate as a chest strap during workouts. This is due to the arm movement, sweat, etc.

Have you tried wearing it even one notch tighter? Are you also wearing the watch away from the wrist bone during workouts? I had the Basis Peak and it was the same issue. Same thing with the Fitbit Surge.

It even says on the Apple support page....

"Many factors can affect the performance of the Apple Watch heart rate sensor. Skin perfusion is one. A fancy way of describing how much blood flows through your skin, skin perfusion varies significantly from person to person and can also be impacted by the environment. If you’re exercising in the cold, for example, the skin perfusion in your wrist may be too low for the heart rate sensor to get a reading. Motion is another factor. Rhythmic movements, such as running or cycling, give better results compared to irregular movements, like tennis or boxing.

If you’re not able to get a consistent reading because of any of these factors, you can connect your Apple Watch wirelessly to external heart rate monitors such as Bluetooth chest straps."

I Am having the SAme problem: vastly different average and real-time readings between my Apple Watch and chest strap HRM. I could understand some inconsistencies but the Watch would say my HR was 60-80bpm when it was between 140-160bpm.

RReally disappointing and I hope it somehow gets fixed soon or I will likely return the watch and wait till the second generatio.

Watch connects with a chest strap in order to correct inaccuracies, however, the strap can only communicate with one device at a time, in my case Wahoo TICKR, the data recorded on TICKR is fine. the strap cannot however connect to the Apple Health and Activity Apps while connecting to the Wahoo App, they also cannot allow the wahoo app to write data to the Apple Apps that would give you correct HRM and calorie burn data. No apparent solution via Chats or meeting at Genius bar

The issue I have with the heart rate monitor is that the displayed heart rate will grey out, not be updated, for extended periods. I use MapMyRide on my iPhone which is paired with a chest strap, but I like to glance at my phone to get a heart rate as my phone display is generally off to save power. When the watch is showing a rate, it generally agrees with my chest strap, but I'd say half the time it doesn't update. I have tried dry wrist, damp wrist, tighter, looser, but nothing improves the reliability.