Garmin Fenix 5s Nested Review

Stock Fenix 5s image from the Garmin Website.

With the release of the Garmin Fenix 5 series, we may be looking at one of the most complex watches ever developed.  Garmin brands this watch as a “Multisport GPS Watch for Fitness, Adventure, and Style.”  With a price tag at $599 and higher, we have high expectations that it will break the mold in the “Fitness, Adventure, and Style” department.  This review is going to gradually cover all of the functionality of the Fenix 5s watch.  There are so many things that this watch can do, there isn’t enough time in my busy schedule to cover them all right away (I do have a full  time job and 3 little kids).  This review will be what I call a “Nested” review that gradually works through each element of the Fenix 5s.  Before we get into it, here is a message from our sponsors, well, you really.  I am completely self run with a little help from readers like you.  I still haven’t covered my expenses yet, but I’m working on it.

I run this site on my own with my own money.  If you like my reviews or my videos, you can support the site by simply purchasing the Fenix 5 from my Amazon link below.  Or, you can click on the Amazon link to the top right of my webpage and purchase anything (baby wipes, diapers, books, anything).  I get a small commission from Amazon sales which helps offset my costs so I stay independent.  It also keeps me motivated to write more articles.  I say that because working full time, being a family man, then staying up late at nights and using my weekends to write articles can be difficult when it comes to motivation.  However, I’m very passionate about Athletic Technology and what it can do for us.  That’s right, I’m a full blown tech geek.

Fenix 5 Purchase Link

How The Nested Review Works

It is 11:06pm on 30 June, 2017 and I just invented Nested Reviews.  Well, I didn’t invent anything, I’m just trying to find a better way to cover some of our more complex athletic technology.  Anyone can pump out a 500 word article on the Garmin Fenix 5s, but how do you review something well without overwhelming people with a 12 thousand word article?  You break it into pieces, and then link everything back to your original review.  All of the branch articles are then “Nested” back to the original article.  Hence, my new review name “Nested Review.”

The Nested Review comprises a primary article that is linked and nested to other articles that provide more detail.

Nested Reviews So Far

This is what I have written so far that is nested within this article.  I’ll try to get to everything by the end of September 2017.

Garmin Fenix 5s Heart Rate Accuracy Review

Garmin Fenix 5s Running Review (Coming Soon)

Garmin Fenix 5s Cycling Review (Coming Soon)

Garmin Fenix 5s Advanced Dynamics Review (Coming Soon)

Garmin Fenix 5s Tracking and Trekking Review (Coming Soon)

Garmin Fenix 5s Golf Review (Coming Soon)

This article will evolve over the next 3 to 4 months.  As I review certain aspects of the watch, I will write an article and then link the summary back to the specific category below.  I may even add categories as we get down the road.  This allows the reader to dive into areas they care about and quickly skip areas they may not care about.  I will also reference other Bloggers if necessary in this article.  I don’t Ski, Snowboard, or Jump out of Airplanes folks!  So, if someone has a great Ski review of the Garmin Fenix 5, then I’ll add it here so you can find that information quickly.


Okay, let’s dive in.  The first thing we need to look at is some of the small differences between the Fenix 5 series, the Fenix 3, and the Forerunner 235/935. I chose to focus my review on the Fenix 5s because it gets us into a smaller watch (usable by both men and women) with the same capabilities.  The easiest thing to do is break down the major differences between these watches in the table below.  I am only going to cover the major differences.  The massive list of everything it does is on the Garmin Website.

 Fenix 3 HRForerunner 935Fenix 5sFenix 5Fenix 5x
Support The SitePurchase LinkPurchase LinkPurchase LinkPurchase LinkPurchase Link
Battery Life-Smart mode: Up to 2 weeks
-GPS mode: Up to 16 hours
-UltraTrac™ mode: Up to 40 hours
-Smart Mode: Up to 2 weeks
-GPS/HR mode: Up to 24 hours
-UltraTrac™ mode: Up to 60 hours without wrist heart rate
-Smart mode: Up to 9 days
-GPS/HR mode: Up to 14 hours
-UltraTrac™ mode: Up to 35 hours without wrist heart rate
-Smart mode: Up to 2 weeks
-GPS/HR mode: Up to 24 hours
-UltraTrac™ mode: Up to 60 hours without wrist heart rate
-Smart mode: Up to 12 days
-GPS/HR mode: Up to 20 hours
-UltraTrac™ mode: Up to 35 hours without wrist heart rate
Display16 Colors at 218 x 218 Pixels64 colors @ 240 x 240 Pixels64 colors @ 218 x 218 Pixels64 colors @ 240 x 240 Pixels64 colors @ 240 x 240 Pixels
Display Size51 x 51 x 17.5 mm47 x 47 x 13.9 mm42 x 42 x 15 mm47 x 47 x 15.5 mm51 x 51 x 17.5 mm
Optical HR SensorYes, but I'm not sure on Sampling Rate.24 x 7 every 1-2 seconds24 x 7 every 1-2 seconds24 x 7 every 1-2 seconds24 x 7 every 1-2 seconds
Bluetooth SmartNoYesYesYesYes
+ ActivitiesStandardMountain Biking, Treadmill, Indoor Track, Ski, Snowboard, Navigate app, Track Me appMountain Biking, Treadmill, Indoor Track, Ski, Snowboard, Navigate app, Track Me appMountain Biking, Treadmill, Indoor Track, Ski, Snowboard, Navigate app, Track Me appMountain Biking, Treadmill, Indoor Track, Ski, Snowboard, Navigate app, Track Me app
+ GolfStandard FunctionsTruSwing Sensor, Greenview, and Autoshot TruSwing Sensor, Greenview, and Autoshot TruSwing Sensor, Greenview, and Autoshot TruSwing Sensor, Greenview, and Autoshot
MappingNoNoNoNoYes, maps on your wrist. Sweet!

Comparison Pictures

I put together some pictures so you can see the differences between some of the different Garmin Watches. It is interesting to see the Forerunner 235 has a smaller body than the Forerunner 935, but the protruding HR sensor on the 235 makes it stick up higher.

I like the 42 x 42 x 15mm design.  It think it the perfect size for both men and women.  I’m not very excited about any watch that starts getting bigger than 47mm in diameter.  That is my personal preference.  The 51mm (Fenix 5x) size for me just seems a bit huge on my wrist.  In the picture below, you can take a better look at how flattened out the heart rate sensor is on the back of the Fenix 5s compared to the Garmin Forerunner 235 that protrudes outwards.

You can really see that the Forerunner 235 wrist based sensor really protrudes out compared to the Fenix 5s and Forerunner 935.


Stock footage from Garmin of the Fenix 5s Sapphire.

Overall, the design is nice, and I mean really, really nice.  This is the Fenix 5s we are talking about, so understand when you are getting the Sapphire, you are getting a watch that is even better.  The Sapphire comes with the Sapphire Crystal lens and a nice steel watch band if you like, but that could set you back near $850.  Not very cheap.  However, when looking at the competition, Garmin did a hell of a job with the Fenix 5s.  The basic 5s works for both men and women and we finally have a multi-sport watch that comes in at 42mm.  The Vivomove is also 42mm but the Fenix 5s has the allusion of a watch that is actually 38 or 40mm.  I like that.

GPS Functionality And Battery

Garmin watches give you the option to use GPS and GLONASS satellite signals.  The US satellites are GPS and the Russian satellites are GLONASS.  They both run on different frequencies, so if you activate GLONASS for increase accuracy, you will lose some battery life.  We will test all the GPS functionality in the future to include the UltraTrac option along with corresponding battery life.  Right now, I am at a solid 7 days recharge time.  (Possible Nested Article in the future if I find something interesting)

This shows the compass face of the Fenix 5s. You can see your heading, Altimeter, and Barometer.
Basic Compass face on the Fenix 5s.

GPS Acquisition Time

The one reason Garmin watches, to include the Fenix 5 series can pick up satellite signals quickly, is they preload satellite locations when you sync with the Garmin Connect App.  This means, the watch knows where the GPS and GLONASS Satellites should be and which ones should be sending signals.  This helps improve satellite acquisition tremendously.  Again, we will add a full review of GPS accuracy down the road if conditions warrant, but I’m pretty sure there isn’t going to be any problems here.

Heart Rate Accuracy

A lot of watches today have wrist based heart rate sensors.  Very few do a good job of tracking heart rate at the wrist for athletic activities.  Most of the time you are better served using a chest strap for the most accurate heart rate.  The only exception is the Garmin Forerunner 235.  For some reason, that watch does a much better job than the other watches I have tested.  (ARTICLE Garmin Forerunner 230 vs 235 vs Vivosmart HR Heart Rate Accuracy).

This is an indoor treadmill run with the Fenix 5s heart rate plotted against the Forerunner 235 and the Forerunner 230 using a Wahoo TICKR heart rate chest strap. The Fenix 5s performs much like the Vivosmart HR.
This test reminded me of the Vivosmart HR test where I looked at performance compared to the Forerunner 235. I am disappointed in the Fenix 5s performance here.

We found the Garmin Fenix 5s performed worse than the Garmin Forerunner 235 when it came to wrist based heart rate tracking.  You can read the Nested ArticleGarmin Fenix 5s Heart Rate Accuracy Review to see all the details and charts.  We had high hopes that Garmin had figured something out when they made the Forerunner 235, but it seems HR tracking on the Fenix 5s hasn’t improved over the Fenix 3 HR.  At least that is what I am seeing from a friend who owns the Fenix 3 HR.

Activity Step/Stair Tracking

For now, activity tracking seems to be working really well.  We need to test the stair tracking further, but this is my first Garmin Watch where I am hitting my stair goals every day.  I wouldn’t say it is perfect, but the Fenix 5s seems to be doing better in the stair tracking department than any other watch or activity tracker on the market.  (Nested Article in the future)

Running Indoors/Outdoors

Stock photo of Garmin Running Dynamics Pod.

We have done a few indoor runs with the Fenix 5s, but haven’t really been running outside with it much at this time.  The indoor distance tracking is very favorable at this time.  I will put some more information up as there are more running activities.


More information coming as a Nested Article in the future.  We will focus on the running performance of this device and how well that new run running dynamics pod works.


I have done a few indoor running tests with the Fenix 5s as compared to the Forerunner 230 and 235.  For one test, I ran indoors for 3.1 miles to simulate a 5K.  You can look at the data below and see that the distance measurement for the Fenix 5s was pretty close.  The treadmill read 3.1 miles and the Fenix 5s recorded 3.2 miles.  That isn’t too bad.  Now, I haven’t taken the Fenix 5s outside for a run yet, so I’m curious to see how the auto calculation of my outdoor pace converts into my indoor pace.  I have ran outside when testing the 235/230 and you can see they don’t do a very good estimating indoor mileage.

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Advanced Running Dynamics

I am curious to see how the advanced running dynamics work.  I’m an average runner and I would like to see how those running dynamics compare to myself versus an experienced marathon runner.  Can I improve my running form?  (Nested Article coming in the future if there is enough interesting data)  We won’t cover Advanced Performance Metrics here like Heart Rate Variability and LTHR predictions.  We will look at those later.

Cycling Indoors/Outdoors

We have been testing the Fenix 5s indoors and outdoors.  It seems to be working well both indoors and outdoors besides heart rate tracking.  I have one outdoor ride below we can take a quick look at with the Fenix 5s compared to a Garmin Edge 520 unit.  The Fenix 5s can also do an FTP test and we should see how that looks compared to the Edge 520.  Also, we need to look at connecting the Fenix 5s to smart trainer signals on our indoor rides.  (This will be another Nested Article in the future)

For this ride comparison, you can see that the Fenix 5s was not on auto-pause.   This means there will be some discrepancy in the data.  We will retest this in the future with the nested article.  However, overall distances and elevation are really close.

Advanced Performance Metrics

There are other advanced performance metrics with the Fenix 5s that need further testing.  You get a specific training load page that displays changes in your fitness.  There is the split between the Anaerobic and Aerobic effect calculations now which Garmin uses to calculate training load.  I need to dig that up and create a chart of some sorts.  I will be updating the Garmin Advanced Performance metrics in a Nested Article in the future.

Other Activities

The list is HUGE on what you can do with the Fenix 5 series.  Here is quick run down of everything this watch can do.  Activities: Run, Treadmill Run, Indoor Track, Trail Run, Bike, Bike Indoors, MTB, Walk, Strength, Row Indoors, Hike, Navigate, Track Me, HRV stress Test, MultiSport, Climb, Pool Swim, Open Water, Triathlon, Ski, Snowboard, XC Ski, SUP, Row, Golf, TruSwing, Project Wpt., Swimrun, Cardio, Jumpmaster, Tactical, and other.

There so many more things on that list of what the Fenix 5s can do and I won’t have time to cover them all.  Working full time and small kids makes it impossible for me to cover everything.  This is where we take recommendations where other writers do a great job reviewing parts of this watch.


Ray Maker from does a great job covering the swim capabilities of this watch.  You can check out the video by clicking on it below.  I don’t have time to do the swim portion of the review.  I was WSQ qualified during my time in the Marine Corps, but I don’t have a lap pool or trustworthy body of water near me to swim.  Furthermore, I don’t trust the water around here to get it in my mouth.  Living outside of Philadelphia… I just don’t trust it.

Ray’s summary, the Spartan doesn’t do a good job in the open water swimming category compared to the Fenix 3 and Fenix 5s watches.  Ray does a great job with reviews since reviewing his equipment is his full time gig.

Weight Training

Weight training is something I’ve done consistently my whole life.  I’ll have to use the GymTime App from the connect IQ Store.  The Fenix 5s Weight Training page doesn’t do a good job at all.  It really only tracks HR and Time.   The Vivosmart 3 has a rep counter on that fitness tracker for your gym workouts.  It counts reps and counts time down in between reps.  The Vivosmart 3 also auto calculates which training workouts were done.  It knows the difference between a bench press and a Lat pull down.  I wish the Fenix 5s had that capability.  We are testing out the Vivosmart 3 in the gym over the next few months to see how well that performs.

This is a quick look of golf course options using the Garmin Connect App. The App pulls up the nearest golf locations according to your phones location.
Your location is used to determine the courses closest to you.


I will also be testing out the Golf capabilities of this watch and see if I can get a TrueSwing sensor.  I once had an 8 handicap when I played golf consistently.  The clubs have been collecting dust for many years now so I doubt I’m keeping things on the fairway anymore.  I do like the setup of the golf features.  Selected a course in the Garmin Connect App was super easy.  It uses your current location to pull up the golf courses near you.  Then, you just select the course you are going to and it is all ready to go.  (Nested Article coming in the future.)


Here is another area where I cannot personally provide experience.  I barely know how to ski, and snowboarding is even worse!  There is only one person out there in Czech that has tested the Fenix 5 for Skiing.  All of the words are in Czech, but you can get an idea of the screens and data.  I’ll update this later if someone else puts together a better skiing and snowboard review of this watch.  Email me if you have one and I’ll gladly add it.

Outdoor Activities

There are a bunch of other outdoor activities I am going to take a look at.  Specifically, I will take a look at the navigation, waypoint features, along with the different hiking features.  The Tactical Feature with the Fenix 5s seems interesting but I don’t see anything in the manual or handbook about it.  I wonder if they just dim the lights so you can see the screen only using NVG’s (Night Vision Goggles)?  I don’t know, I’ll check that out later when we build our Nested Article on all things hiking and navigating.

Smart Notifications and Other Things

Smart notifications work as expected with the watch.  I also like the shortcut screen you get by holding down the light button.  It allows you to quickly navigate to things you need right away without digging through menus.  You can see the images I posted below of the different screen shots we haven’t looked at yet.  The “Find Your Phone” feature also works really well and I’ve had to use that feature once before  (yep, the kids got my phone).

Customization and Apps

Garmin really hit a home run with the idea behind Connect IQ.  The ability to customize not only the Fenix 5 series of watches, but most other Garmin watches is brilliant.  You won’t find another watch that has so many customization options.  The Fenix 5s comes with 64mb of memory where the Fenix 3 HR is running on 32mb of memory.  However, I will note, that the Forerunner 935 is also running 64mb of memory.  That is an important thing to remember when making a purchasing decision.


As a consumer, the main decisions you have to make are really based on looks and price point.  If I could afford the Sapphire edition, I would definitely get it.  That is one great looking watch.  The same with the mapping capability.  If I had the extra spending cash, why not have maps on my watch.  That would be really, really cool.  I just want to break the hard decision down real quick.

The Fenix 5 and 5s comes in at $599.99.  That means you only need to decide if you want a smaller or big screen face for your watch if that is your price point.  I choose smaller because I don’t like big huge watches on my wrist.  The other purchasing decision is between the Forerunner 935 and the Fenix 5s.  The Forerunner 935 costs $100 less at $499.99.  I will say that the Fenix 5 series looks nicer than the Forerunner 935 does.   However, I don’t think it looks $100 dollars nicer though.  I would be perfectly happy with the Forerunner 935, and even happier if I could find it at $450.  Now, if all of this is out of your budget, then I highly recommend getting the Forerunner 235.  Just take a look at the Heart Rate comparisons we did in the nested article above.  The Forerunner 235 does a better job tracking wrist based HR than these other watches (excluding the 935 which hasn’t been tested yet).

I will try to find some time in the next few months to put some more articles together.  I enjoy doing tech reviews.  If I didn’t enjoy this, there is no way I would be spending hours up late at night and weekends researching and reviewing tech.  If you would like to support me and purchase a Garmin watch, click the links below.  I earn a small commission on sales.  Also, you can navigate to the top right of my website and purchase ANYTHING on Amazon from my link and I earn a small commission.  Thanks for reading everyone!

Purchase Fenix 3 HR

Purchase Fenix 5s

Purchase Forerunner 935

Purchase Forerunner 235

Aaron Johnson

Aaron Johnson

Aaron served in the military for 20 years. Multiple tours in Iraq and Afghanistan. He retired from the military after 20 years of service to take care of our three small children in 2013 as a Stay At Home Dad.

athletictechreview has 60 posts and counting.See all posts by athletictechreview

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