Doesnt matter what setting I use, the heart rate monitor fails to read or reads incorrectly almost every time i workout. Today i tried to uae the cardio app to record my calories and heart rate for a high intensity workout.... 45 minutes with 20lb weight vest... burned 3 calories and got one, yes 1, heart rate reading of 95. Slowly starting to lose my patience with garmin. Basically i have an over priced stop watch on my arm, I could have gotten 3 dozen timex watches to do exactly the same thing. Next step will be retun and refund. No reason to have it if it isnt going to work properly.