Fitness monitor distance v treadmill

[RebeccaSK]

This is a weird one. At the moment, for various reasons, I'm running mostly on a treadmill. I also wear a Garmin Vivosmart HR. Thing is, the treadmill and my Garmin are telling me completely different distances and different pace rates. My Garmin when I run outdoors is always accurate as I also track my runs via MapMyRun. I'm inclined to believe the treadmill but I want to believe the Garmin as it normally claims I've run further than the treadmill!!!!! My Garmin does NOT have GPS on it. Has anyone else experienced the same kind of thing?

[MarkyD Graduate]

Yes of course! The treadmill doesn't know your stride length and so it is always going to be approximate. Just measuring the distance that the roller travels.

The Vivosmart also doesn't know your stride length, but it can measure/count your steps, the length of time in the air between steps and even the ground clearance as your foot travels through its running arc. So it can be more accurate. But still not perfect.

As with all these gadgets, the important metric is day-to-day changes. Regardless of the exact distance run, are you running further than your last run. Or is your pace consistent and/or getting faster.

If you plan to run outside in the future, I suggest that you continue to believe your Vivosmart.

And whilst I am here, don't expect to get a scientifically accurate HR from the watch. Use the metric to give you an idea of your training intensity day-to-day. But don't try and compare it with a medical instrument.

[Bazza1234 Graduate in reply to MarkyD]

None of these gadgets are completely accurate - but it doesn't really matter. If you are using the same piece of equipment daily (either watch or treadmill) , then it matters not whether the pace it shows is completely accurate - what is important is to know what time you have run for each day and what pace the gadget shows you. It simply means that you take that pace as given and then compare it to what you do tomorrow - is it faster or slower tomorrow? What we are all really looking for is improvement and we can see whether that is happening or not regardless of the accuracy of the piece of equipment.

[RebeccaSK Graduate in reply to MarkyD]

Thanks MarkyD and Bazza1234. I'm not too hung up on making sure I'm running further (and definitely not faster at this stage). I am improving still - on W8 - and, as you say, that's the most important thing, but when you feel like you've given it everything you can (as I do most of the time) then I want to know how far I have run - and if my Garmin is the more correct of the two then it's a bigger confidence boost!

As for the HR - I long ago learned not to trust that but, on the whole, I think it's fairly accurate - it spikes where I'd expect it to spike and falls back down when I'd expect it too.

I don't obsess over my Garmin stats - but I do find it's a useful motivational tool for me. I don't expect wearing a Garmin to automatically make me fitter, but I do like to see the progress I'm making to drive me on further.