Today I used my Tomtom Runner for a tempo run targeting a particular HR zone for the first time. I have figured out how to set up interval sessions, but I realized today that I hadn't yet used the device for HR training. The first step was to make sure that the zones were set up correctly. I logged in to Garmin Connect and wrote down my HR zone info that was configured in my settings. I have used these zones for many workouts and trust them to be correct (enough). I then transferred the information to my profile on the Tomtom website. Setting up the zones on the Tomtom site is very easy - enter the max HR and then just slide the limits into place. High marks for usability. After re-syncing the device, I selected Zone-HR from the training menu and then selected "Endure". (The plan today was for 40 minutes in Zone 3, which in Tomtom-speak is named Endure.)
The run itself was OK. It was cloudy, dark, cold and windy (3C with a wind chill of -1C) and I was feeling a bit sluggish. The zone training on the Tomtom was interesting. The device is very good at telling you when to speed up and when you are on target. It completely forgets to tell you to slow down. I found that I was blowing out the top of the zone and only realizing it later when I saw what my actual HR was. Once I slowed down a bit, I was told that I was on target again. For effective zone training, staying in the zone is critical and Tomtom needs to fix that. I did my best to stay in the zone and my average pace indeed decreased in the second half of the run, but after turning around at exactly 20 minutes, I still nearly finished where I started - two city blocks behind. In my books, that's not too shabby.