Hi, I've posted a little about some behaviour that I don't understand over in a thread about continuous monitoring by the HRM-Tri strap, but I'd like to open a new thread regarding this behaviour as its separate from continuous monitoring when outside of an activity, and either a bug or some setup option that I have missed.
I have previously trained and competed wearing a Forerunner 610 with an accompanying chest heart rate strap.
I purchased the 935 Tri bundle two weeks ago and started running using the packaged HRM-Tri strap. When I put the HRM-Tri on, I get notification from the watch that it is connected, and the watch itself is set to automatically set my upper HR (currently at around 193), and resting is using average of 50bpm. I have been keeping the watch on the HR screen so I can see what my HR is during the run.
I noticed that upon long run completion, the TE values were often 5.0 and 0.0, so scrolling around the menus post race I noticed the DOWNLOAD HEART RATE option. I selected that and the watch seemed to pull data from the HRM-Tri and then processed them. The TE values generally changed quite dramatically, along with other metrics (the TE was the one that caught my eye).
It has been suggested to me that perhaps my watch was losing the connection with the HRM-Tri mid run, and using the OHR instead, so DOWNLOAD HEART RATE was feeding the watch with more accurate data post run. Today I decided to test that out.
I ran 15km or so today, with the Wrist Heart Rate sensor disabled (Settings/Sensors & Accessories/Wrist Heart Rate/Status -> OFF). I put the HRM-Tri on, and the watch said it was connected, I waited for a GPS signal, and started my Run activity. The screen was set to display HR so I could see whether it was reading from the HRM-Tri, and at no point during the run did I see a blank value on this screen.
Upon completion, I saved the run and checked out the TE values:
5.0 aerobic
0.0 anaerobic
Thought that was a bit strange, so I clicked on DOWNLOAD HEART RATE to see what it would do (note that the Wrist Heart Rate sensor was disabled, so the watch has only used HRM-Tri data to calculate that TE value). The watch showed me the DOWNLOADING STORED HR DATA screen, then the PROCESSING DOWNLOADED HR DATA screen, then HR DATA DOWNLOAD SUCCESSFUL. I then checked the TE values:
2.9 aerobic
2.0 anaerobic
Can anyone explain why this is happening? Are people who are not selecting DOWNLOAD HEART RATE following a run activity when they are using an HRM-Tri getting inaccurate data? Is there some setting burried somewhere that I've missed or incorrectly configured?
Why are the values take pre and post DOWNLOAD HEART RATE so different if the watch has only used the HRM-Tri during a run?
