| Garmin Fenix 5s | First Run With STRYD | Drop Outs? or PowerTastic?

STRYD Garmin Fenix 5sThis follows on from my highly successful series of ‘First Run With…’. We had: first run with the Polar V800 and STRYD; first run with the 935 and STRYD; first run with will.i.am and STRYD; and now it’s the turn of the Fenix 5s. With STRYD.

This little ‘first’ run of 10-and-a-bit miles has the potential to be the most interesting of the lot. People are having issues with the Fenix 5s and 5 not properly connecting to some 3rd party sensors, STRYD being one of them. It was also a GPS test for the 5s as well…my first glance at the GPS tracks was NOT good. Let’s see what I found.

Before we start: FYI I have only done 3 STRYD runs with the 5s and several more with the 5s WITHOUT STRYD. Bear that sample size in mind. I also used the STRYD on my right shoe and watch on my left wrist – slightly further apart than using the right wrist (it could make a difference).

spartan 5s suunto garmin 935 fenix
L-to-R Suunto Spartan (5x kinda size), 935, 5s, Epson 810

The Fenix 5s is a nice watch. It’s well made and feels more substantial than the 935 despite its smaller size. It’s smaller size has an aesthetic appeal in itself even to those who might not just have small wrists. And it’s overflowing with features.

REVIEW: Of the entire Fenix 5 series (including 935) is (here)

Getting STRYD to pair and work with the 5s is pretty much the same as for other, recent Garmin devices. It’s very straightforward and pretty much the same as you would pair any basic sensor:

  • Just pair it to the Garmin as normal for any sensor (optionally and sensibly set STRYD ALWAYS as the source of speed & leave auto calibration enabled in the sensor properties)
  • Make sure you have already downloaded the STRYD data field (not the app)
  • Add the data field onto one of your screens
  • That’s it. You’re good to go.

One of the first things I found running with STRYD is that the pace is suddenly more stable. The displayed fluctuations in PACE all seem plausibly the same as the real fluctuations in your real pace. There is a very slight delay with STRYD. From memory, I think it works with 5-second averages so hopefully you will appreciate the effect of sudden pace changes.

I also had the Garmin 935 on my other wrist and a Suunto SPARTAN SPORT in my back pocket. All 3 devices recorded power and, FYI, I was also looking at the oHR accuracy of both Garmins.

So here is the data. In theory it should have been a steady state run for 90 minutes. The 23 minute and 1 hour troughs were probably from a dog walker or similar. Ignore those. Unfortunately for the 5s there is clearly a drop out at 51 minutes and also at about 2 minutes.

Those 3 curves should be IDENTICAL. The same sensor is the source for all 3, even thought the Suunto is capturing the data over Bluetooth SMART.

Being fair to the 5s I never noticed either of the dropouts in the run and I actually noticed a bit of silliness going on with the 935 at one point but that was probably induced by me.

Being even more fair to the 5s, having just one/two dropouts over 90 minutes is fine for me. Those dropouts will have virtually no effect on the cumulative data from the session and, as I said, I never even noticed it whilst running.

But then again why should you accept an obviously lower standard of data/hardware compared to other watches that clearly are perfectly fine? Especially when you’ve paid good money for the 5s?

Q: Would I send it back?

A: Probably not based on that experience. But I would be nervous

EDIT: Oh dear. Just did a 3 hour bike ride Edge820+935+BePro with the latter in boosted signal mode. The 935 dropped power about once every 10 minutes. Totalling a lost 2watts from the average. And then I looked at some earlier rides. Guess what?….more drops.

Here’s a STRYD powercenter chart from my proper first test run of just a couple of KM with 5s/STRYD. It gives you interesting additional metrics which although you can see in Garmin Connect are better analysed elsewhere.

You can see that I am broadly speeding up over the 8 minute period. Pace and power go hand-in-hand as I was running on a flat road. The top curve is my FORM POWER. That is the power required to hold my form and the lower it is the better, I think of it as ‘wasted power’. You can see that as I get faster proportionately less power is wasted. Maybe that’s a self-evident truth. It was interesting to me at the time.

I then wanted to get all the data into SportTracks 3.1 (desktop) so that I could produce that first overlay chart for you guys. No power came through. Grrr. This has been the case for a while for power from FIT files imported directly from Garmin devices. If, instead, I exported the data from POWERCENTER and then imported that into SportTracks then OMB’s plugin DOES import the power data. So there may be something wrong with: the Garmin watch; or how STRYD have written the data field; maybe even with sporttracks. I think people are aware of this but I still can’t see the solution. Angus?

I’ll post something separately on the GPS accuracy of the 5s. It does NOT look awe inspiring from a quick few glances. But I need to spend a bit more time to come to a considered view.

STRYD Recommendation for the Fenix 5s: Tread carefully young Padawan if STRYD power is your thing. Make sure you can return the 5s if the 5s doesn’t work as advertised! Or go for the 935 which has been fine for me with power over numerous runs – it’s a similar size, even lighter and basically the same firmware inside.


I partner directly with STRYD in the USA and their distributor New Running Gear in the EU.

stryd discount code coupon offer special price



Best REI/Wiggle/PMC price is linked to.


Reader-Powered Content

This content is not sponsored. It’s mostly me behind the labour of love which is this site and I appreciate everyone who follows, subscribes or Buys Me A Coffee ❤️ Alternatively please buy the reviewed product from my partners. Thank you! FTC: Affiliate Disclosure: Links pay commission. As an Amazon Associate, I earn from qualifying purchases.

9 thoughts on “| Garmin Fenix 5s | First Run With STRYD | Drop Outs? or PowerTastic?

  1. Yes to all this review. I will say this though in regards to your sample size; it really isn’t large enough. If the 5s is anything like the 5’s issues, those dropout WILL get progressively worse. Took a month for me to really notice it, but dropouts went from approx (1) drop to upwards of (8). And those were just from Stryd, my HRM-Tri followed suit and it wasn’t an issue at all at the start. My speed and cadence sensor on my bike also had a ton of issues.

    Thanks for doing this, people need to see (and read) the issue from people outside the “Garmin bubble” sometimes.

  2. Thought I’d drop by to help with the SportTracks issue. AFAIK it goes as follows: when Stryd Powercenter produces a .FIT file at export they direct the compatible Stryd data at corresponding standard tracks automatically. This means the more established additional metrics like Power, GCT, VO. On their own platform they can do this easily.

    When you export an original .FIT file from Garmin Connect the data is still in its respective IQ data tracks. This is because the data was recorded directly from the watch and has original data sources from the watch still intact. So working with the original file you have to do it yourself manually in SportTracks. That means for example using the OMB custom data tracks plugin and then copy the Power IQ track yourself to the standard Power track.

    Hope this helps 🙂

    PS. This could change in the future when Garmin has announced to open running dynamics open to 3rd parties and seems that Running Power could get added to the ANT+ standards as well.

    1. that helps, thank you. I thought it was something similar to that
      so it’s sporttracks fault then!! (not OMB as he is following the standard to the letter – as always!!)

      1. Well kind of yes. It would surely help if SportTracks was updated to better support handling of IQ data out of the box. In its current state it’s mostly clueless about what kind of data the 3rd party plugins have. The built in data tracks tool for example can only deal with default supported metrics. It lags behind in other functionality as well, like properly exporting/importing elevation data, stripping out GPS data etc. Luckily OMB has some great set of additional tools available!

        It’s also kind of Garmins fault that it’s taking so long for them to acknowledge running power as a viable metric to record natively. If it did that then there wouldn’t be any problem to begin with. At least there is now some indication that it could be possible to happen (hopefully) in some near future.

      2. st seem to have abandoned st3. strange as many of their users are NOT the same types that will use their mobi version . they will probably lose many of users like me to golden cheetah.

        yes with supported metrics…I also want to be able to just create 5sec moving average power and have that usable EVERYWHERE as a ‘normal’ metric.
        I think maybe the data cleansing could be argued to eb outside of their remit (I use fit file repair tool…which is awesome and, for example, cleanses elevation data).

        garmin: I suspect they have ‘other’ plans and are doing what they are doing because of specific intent. eg competitor to stryd. we shall see. they are certainly not making it easy for stryd.

  3. As a long time Garmin fan, I’m having a very hard time defending them with these Fenix 5 dropout and GPS issues. I’m so sick of getting the run around from Garmin customer service and the “wait for new firmware” and “you need to use Garmin ANT+ devices” comments. Even my HRM-Run has dropouts.

    Based on my conversations with Stryd, they claim this is a problem with a weak ANT+ signal in the Fenix 5/s. For a $700 flagship device, Garmin needs to give us some options to get this resolved, even if that means buying back the F5 for us who are incredibly unhappy.

      1. Yeah, got my words mixed up.

        “But yes, it is clear that the signal is weak / shorter antennae and searching for bluetooth / ant+ on different levels than it should. Not sure how Garmin can/will fix this either.”

Comments are closed.