Just a very quick question, I got another PB in my Parkrun on Saturday - 29.20 (which I'm so chuffed at, considering I've only been running 7 months) - anyway the majority of my run (according to my phone heart rate zones - Samsung Health) was in the Maximum zone - 163-181 bmp. How accurate are these monitors ?? I felt fine after my run, and once I stop running it takes about 30 seconds or so to get my breathing back to normal. Should I be worried by these stats ??
Thanks all for any advice !!
The general consensus seems to be that the HR monitors on watches aren't as accurate as chest monitors. They can confuse your cadence (number of steps per minute) with your heartrate. Apparently you can minimise this by making sure your watch is fastened as tightly as is comfortable before you set off for a run.
As one of the many who don't have a chest monitor I can tell you that my runs are consistently in the Maximum zone unless I very specifically choose to run slower.
Lately I've been trying not to look at my watch as I run and to stick to a comfortable conversational pace. Despite this the HR is frequently high. Like you, it falls rapidly once I stop running. The only time I feel uncomfortable is if it's above about 150 bpm, when I get a sort of uncomfortable feeling in my chest and know I need to slow down.
There are things you can do, like seeing a sports physiologist to get an accurate assessment of your zones, but I think a lot of us just take the numbers with a pinch of salt.
As Yesletsgo says, it's unlikely to be correct, if you were that close to maximum you'd be gasping for breath and would struggle to keep it up for a whole 5k. That's a brilliant time though, I'd suggest between parkruns you run a ,5k at what is called conversational pace, being able to speak whole sentences aloud (softly unless there's no one around) see how long that takes and base that as your easy pace, then you can see how much faster your parkrun is. If you get to the end of a run, any run, and collapse gasping in the ground, feel shaky and a bit sick you've overdone it. If you end with a grin and as you've said your breathing and heartrate quickly return to normal you should be fine 😄
Make sure your heart rate setting on the watch is the right one for your age. You can also look up hr zones online and set yours accordingly. I know there is a test for Garmin too find max hr, not sure about your watch. Personally, I find that my HR can get very high going for a pb in a parkrun, it sometimes goes to red and I do sometimes react to it by slowing down. Btw, my HR settings were toi high when I first got my watch and most of my runs were in the red zone 🤣.
Determining your max HR
40 min run with a new phone holder sleeve 
Keeping on keeping on
