Heartbeat is incorrect at training for some time

Astrid71 Registered Users Posts: 9
Apprentice Traveler
edited January 24 in TomTom Sports

Last months the watch is not working o.k.
Mostly halfway my trianing the watch gives an inorrect heartbeat.
I cycle, untill that moment, for example with a beat of 145 b/m.
And then suddenly he shows, for 15 min or so, that my heart beats 88 b/m.
The watch is really close/thide around my wirst/arm.
So the whole training gives incorrect information afterwords.

What to do?

Greetings Astrid


  • tfarabaugh
    tfarabaugh Posts: 16,943
    There are two issues around heart rate using optical HR monitors, and these are on all devices, not just TT ones: low heart rate and HR spikes. Low HR is often seen in rowing, cycling and weight lifting. Any time you do an activity that squeezes or tenses the forearms (like the pull stroke in rowing, bearing down on your handlebars in cycling, or virtually any weight lifting move) you are squeezing the blood vessels the watch is reading, so it sees this as a reduced pulse. It is not that the watch is having a problem reading your pulse; it is that your pulse at the wrist has dropped because you are temporarily cutting off blood flow to the vessels it is reading. I have experienced this with every optical HR I have used, including a Mio and a Scosche unit. For these sorts of activities, you are better off using a chest strap synced to the watch if getting a more exact reading is important to you.

    I hope this helps answer your question. If so, please mark it as a solution so others can look for it if they have the same question.
  • Astrid71
    Astrid71 Registered Users Posts: 9
    Apprentice Traveler
    Cross posting