Polar Grit X vs. Vantage V: Let’s Head for the Hills

The Polar Grit X is made for the outdoors, especially for the mountains. After a look at a quick first run on the flats, then, I also went for some hill repeats to get a first impression there.

Quick note: I am still only comparing Polar Vantage V (which I wore on my right wrist) and Polar Grit X (worn on my left wrist), with additional data only from the Polar BEAT app running on my Samsung Galaxy S9, connected to a Polar H10 heart rate belt.

Comparisons with other watches from other brands will come later, by and by.

There is also a look at how the Polar Grit X’s new Hill Splitter functionality interprets and helps to interpret such hill data, here.


Polar Grit X and Vantage V are both equipped with barometric altimeter. Both also auto-calibrate altitude via GPS at the beginning of a session (and have no function for manual calibration of altitude).

Clearly, auto-calibration either didn’t kick in or was not successful; it’s the Vantage that is shown at too low an altitude.

Overall, with a few small differences, I’d say that the altitude graphs are sufficiently similar between the two watches and between laps (these were five laps on the same route) to be fine with them.

There is only one “chasm” in the third lap, as recorded by the Vantage V, where something untoward happened. I didn’t have a shirt sleeve over the watches, nor do I think that I had sweat get into the baro sensor, but those two would be the most common explanations for such spikes.

In case some oddities came about because the x-axis is now set to use duration (and I was slower on the last lap, I’d think), let’s also check how it looks by distance:

Even more similar, I’d say.

GPS Tracks Recorded

To make it extra-clear that these were indeed five laps on the same route, here’s the GPS tracks recorded:

The orange one, that’s the smartphone.

I kinda love this, given I regularly see people who think that smartphones surely have large antennas and big batteries and get exceptional GPS reception.

Not so.

Grit X and Vantage V mainly show the usual offset from one watch being on the left arm, the other on the right.

And thus here, where I turned back around to my right, the Vantage track looks tighter…

Whereas here, having always turned left, it’s the Grit X that’s giving tighter tracks. They are also more consistent, however, so maybe there is a difference in GPS reception.

Distances recorded are as is to be expected:

Polar Grit X: 8.08 km
Polar Vantage V: 8.15 km

70 meters of difference between the two over a distance of 8 km, that’s less than 1%. Not exactly anything to complain about.


This is peculiar… or maybe easy. I can’t remember ever before having seen pace in the data exported from Polar, and there is probably something still wrong with its export.

When I export the .tcx from Polar, this is what I get for pace in Quantified Self (which I use for comparisons and analysis):

Even zoomed in, the Vantage V pace looks like there’s hardly any variation.

Comparing the pace graphs from Polar Flow, it’s clear this is some data (export) problem:

Hill repeat paces, Vantage V above, Grit X below

This looks more like actual pace recordings – and though there are some similar trends, this does indeed (as people have suggested) look rather bad for the Vantage V, more consistent (especially comparing between laps) for the Grit X.


This run, I also used the Stryd… and it promptly failed on me. Still, we can compare what power was recorded by Grit X and Vantage V.

These actually look quite similar, surprisingly enough (given the differences in pace, for example). Looking closer…

This was just for one (the second) lap – which is why I’m also showing the altitude profile.

Indeed, the power recorded was quite similar.

Heart Rate

The first impressions of heart rate from oHR, from my first easy run with Grit X and Vantage V, looked really good for the new watch – and not horrible but not nearly as good for the Vantage V.

Hills can be a different issue, though…

… as they turned out to be, to some extent.

The performance of the Grit X’s new Precision Prime 2.0 is still much better than the Vantage V’s – but not nearly as close to the chest strap’s recording all the time anymore.

The zoom into the second lap’s/hill’s data may give a hint why:

With the “climb”, the curves diverge. My heart rate rises, the chest strap captures that well, the oHR sensors get confused.

With the downhill running, things get better. Much faster with the Grit X, later also with the Vantage V, though.

This seems to hold true over the whole course of this hill repeat – I think:

Grit X oHR recording vs. Polar BEAT (H10) recording – with altitude
Vantage V oHR recording vs. Polar BEAT (H10) recording – with altitude

Definitely a better result from the Grit X, but a pretty imperfect one. And interesting that the penultimate downhill’s and final full lap’s recordings were pretty good for both oHR sensors.

Lap 5 altitude and oHR (vs. H10 chest strap) recordings – largely good

Preemptively versus good questions and stupid comments: I wore both watches the same as on the easy run before, in a similar position, similarly tight (but not too tight).
There was no need to push up on my knees during the “climbs” or do anything like that.

There could possibly have been some influence of the time(s) I held my camera while running, but I switched that around between hands.

It looks more likely that there is something about the beginning of the climbs, in particular, that ‘hurt’ the oHR recording.

It looks a bit like maybe there was some warm-up issue, but I had already ridden my bike to the start of the run, so I doubt it was that. But perhaps.

As always, more data and better analysis is necessary to really give any verdict, anyways. This is just an n=1, in more than one way.

One person, one case – nothing to draw definite conclusions from.

Let’s see about more!

4 responses

  1.  Avatar

    The Grit X now has the ability to calibrate altitude in session – press the middle button on the altitude screen.

    1. Ah, thank you so much! (I think I had actually heard that mention, and promptly forgot about it again – and hadn’t needed it, so probably would have forgot about it forever!)

      1.  Avatar

        Yes, I also wish they could at least add an outdoor widget screen for the Grit with ABC tools, given how nicely Polar presents information on the watch!

        1. Heh, true. Polar is so training-focused (for me), I didn’t quite notice the absence of that. But compared to any other outdoors watch, it *is* missing

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