I’ve been using my Garmin Forerunner 255 watch for about a year now and mostly I quite like it for my runs. I get a nice array of stats, it presents lovingly in a web interface, as well as in the requisite app. It performs well and remains easy to use in all kinds of weather. It’s accurate.
Well, it was accurate until today.
As you can see by the chart below, my heart rate went up rather dramatically right near the beginning of the run, when my BPM is usually on the lower side (since I’m just starting my workout). It then stayed really high (pushing 190) for a little over the first km before abruptly dropping down and staying in a typical range for the rest of the run.
I first suspected something was up at the end of the first km, when I got my usual performance conditions alert. This puts together various stats to give me a rating of how the run is expected to go. I usually see it fall in a range of -1 to +2. Today it reported -9, which I think would normally mean it was making the assessment when I was still laying in bed at 6 a.m.
I did check my heart rate later in the run several times, when it reported 151 and 155. I think 155 is probably close to the actual overall average.
At the end of the run I got a message about how it had “adjusted” my heart rate somehow, along with a context-free “+180” and I still have no idea what the +180 was referring to. I can’t find the message now and wish I’d taken a photo of it with my phone, but alas. The best I can guess is it was adjusting the overall heart rate based on the spike, making it 160 overall.
But mainly I think the sensor wigged out for some reason. I’ll probably power-cycle the watch or check for updates before the next run, just to be thorough (though once it settled back down, it was fine, and reported normal activity for the 4 km walk home).
As for the actual run, I had four days off, so I was feeling a little rusty, but no issues to report otherwise. It was drizzly, and my glasses started getting coated, but at least it was much milder than Friday’s run. This was also the first run since the storm bearing an atmospheric river came through, and sections of the trail were either washed away or in otherwise rough shape. A quite large tree at the start of the Spruce loop did not survive:
The freaky heart rate kind of spooked me, even though it was almost certainly a sensor glitch (I checked as I was writing this and there is, in fact, an update for the watch due out today or shortly after), but the run itself was pretty normal for four days off.
Stats:
Run 835 Average pace: 5:47/km Training status: Maintaining Location: Burnaby Lake (CCW, short loop) Start: 9:42 a.m. Distance: 5:03 km Time: 29:04 Weather: Cloudy, drizzle Temp: 8-9ºC Humidity: 91% Wind: light BPM: 1601See the explanation below for this (probably more like 155) Weight: 169.8 Total distance to date: 6065 km Devices: Garmin Forerunner 255 Music, iPhone 12, AirPods (3rd generation) Shoes: HOKA Speedgoat 5 (200/368/568 km)
