Originally Posted by
twodownzero
I keep mine on cadence nearly all the time and keep track of my current speed and cadence to make sure I'm not slacking.
I don't have a garmin, though, I use a Cateye Strada Cadence.
I purposely don't even display speed much of the time because I find it encourages me to work too hard. HR + cadence strike me as a good way to make sure effort is where it needs to be.