When i run with the 'run' activity selected my heart rate is at around 160 for the whole run. Its fairly sustainable as i can run for an hour sometimes. I did a quick shuttle run workout the other day where I ran a 20/40/60 metre shuttles. I was running the whole time however, I didn't select the 'run" activity. My heart was beating out of my chest, I was pretty much at failure and have never been so exhausted. I later looked at my heart reading and my heart rate only went to a max of 129. I checked my pulse during the activity and my heart was beating faster then I've ever felt it, if not the same as the 160/170 heart rate I experience when running with the activity on. Ive noticed similar experiences during workouts, when I dont input an activity, do a hard workout and it only reads my heart rate as 110. ive also noticed it rollerblading with the bike activity on (I dont know how to put inline skating activity on the watch) where I feel failrly not out of breath, breathing through my nose, and yet my heart rate is listed as 120. it seems like when an activity is selected and on, it automatically assumes or registers your heart rate higher then what it actually is in some instances.
I am wondering if Garmin watches changes the heart rate sensor in some way or measure the heart rate different when an activity is selected? Does it read more accurately or does it adjust the reading in some kind of algorithm to get the correct reading? Its confusing because during the shuttle run, although I was abruptly changes of directions, I was still running around the same pace, and for the 60m sections, surely it would be able to read my heart rate as accurately as when I am doing a 5/10k? Or is this just a fault of the wrist based heart rate?
Thanks
