Garmin Fenix 5s and Forerunner 935 Review

Both watches are great pieces of kit, however before I start I need to say that I’ve used a very small fraction of what these watches are capable of. As I’ve mainly used the running modes.

The fact is both watches are expensive, as of January 2018 they are north of £400. Whilst they are expensive sports watches, at that price you’d want them to pretty much track every activity, which they do. There’s a lot of activities covered from, running, hiking, strength, cardio, elliptical, golf, boating, swimming, triathlon, skiing etc. All the way through to parachuting!

Forerunner 935

There’s a lot of Garmin watches out there, aimed at everyone from beginner runners to performance triathletes, so it’s very easy to overspend for features you don’t really need or will probably never use. The other photos are at the end of the article. 

In the case of these two watches if you want advanced data and do multi sports, then they are both are for you, but if you are a beginner and just want basic features to record your run then I’d recommend the Garmin Forerunner 35.

Essentially both watches have similar internal architecture. The 935 is a Fenix 5 in lighter plastic case.

If you are a triathlete then the 935 is the better choice, as it has a longer battery life than the Fenix 5s. In GPS mode it lasts 24 hours and two weeks in smartwatch mode. Whereas the Fenix 5s lasts upto 14 hours in GPS mode and nine days in smartwatch mode. However both factors are dependent on usage and whether you use the smartphone alerts connectivity.

Rather than bore you with all the technical features, I’m just going to focus on what I do and don’t like about both watches, coming from someone who who used the Garmin Forerunner 630 prior which is still is an exceptional watch for covering advanced running metrics.

Ok so let’s start with what I don’t like

  1. Firstly I do miss the touch screen element, from the 630. The first few times I kept unconsciously tapping the screen of the Fenix 5s and Forerunner 935! Especially when changing songs on my phone. It’s more of a phaff with the buttons;
  2. Whilst the optical heart rate monitor does a good job, it’s not as accurate as the external heart rate strap, which I would recommend in addition to wearing the watches whilst training. Whilst both watches are still great and give you a lot of data, such as what your cadence is. If you want that extra bit of data you need to have an external heart rate monitor, which is an additional cost. With this you can monitor stride length and a number of other features included vertical ratio, which is useful for boosting your running efficiency.
  3. I was keen on the new running data metrics in theory, but in application I think they are slightly flawed, which I think has something to do with the optical heart rate monitoring. So to give you an idea of my training schedule, I run seven days a week, the majority of my runs are at an easy heart rate monitored pace. And I have several key regular workouts repeated each week where I run hills, intervals, tempos etc. Looking at the VO2 Max measurement, the problem is on the easy running days, the data says my baseline fitness has dropped, but when I run at tempo the data says it has improved. But as I don’t run tempo runs everyday there is a slight variation wherever you are in the week, as to the state my fitness. But overall it does balance itself out;
  4. For the training status measurement, for example after 3 days of easy paced running to work on my aerobic side, it said I was overreaching and my fitness had dropped. I would respectfully disagree…
  5. Whilst I like the idea of digitally monitoring the anaerobic and aerobic effect of each workout, I feel again it’s less accurate without the external heart rate monitor;
  6. Finally there is a measurement for recommended recovery time before running again. Whilst useful I feel like it always goes on the side of caution with the recommended rest periods, especially if your used to running daily or do double sessions.

With new watches, needing to be better than the last, it feels as if the promise of this extra data would add more, but in my case, I feel it actually puts the progress of the watches back. It’s difficult to be too critical because the watches do so much, but the data shouldn’t be used as gospel as there will always be minor inaccuracies.


Let’s finish on what I do like

To sum up both the 935 and Fenix 5s are great sport watches by Garmin who produce quality products, which I’d highly recommend.

  1. Outside of running I like the other elements it monitors, such as your daily heart rate, where you can see what it typically looks like over a day, week etc. Then you can look at your stress levels and monitor this;
  2. The monitoring of your sleep, in terms of total time, looking at deep to light sleep;
  3. Plus it tells you how many steps you’ve taken, stairs climbed etc.
  4. Probably due to orienteering from scouts I really like the compass! Yep I know simple things!
  5. Plus the smartphone connectivity is great, but it will use extra battery;
  6. Finally looks wise the new watches have come on a lot. I prefer the smaller Fenix 5s as my day job is office based and I feel it looks abit smarter than the 935, against a suit etc.

In terms of running, it does a great job in monitoring my running data. But in all honesty an upgrade to either wasn’t necessary for me personally, over the Forerunner 630. Whilst the extra features are useful, they haven’t really changed the way I view my training data for reasons previously noted.

As a runner reviewing these watches, I’m only scratching the surface with the full capabilities of what these watches can actually do.

If you want that extra bit of data, and your a triathlete go for the 935. Like I said the internal architecture of the multi sports features is the same for both watches, but the Fenix 5s the battery life is smaller. But go based on your personal preferences as to which one to choose.

Thanks for reading and if you have any questions ask me in the comments section below.


Forerunner 935img_1398img_1400img_1399


Fenix 5simg_1407img_1410img_1408


  1. I could imagine you as a scout. And love the parachute function! I’m a big fan of Garmin. Have a fab New Year!

    Liked by 1 person

  2. They call me Mr running D says:

    You got the nail on the head. Unless you do multi-sports, and have the money, these watches aren’t the best choices for most runners. I was very tempted to get the Fenix 3, but I’ll most probably go for either the vivoactive 3 or the Garmin forerunner 235. Are you going to keep both watches? Good review.

    Liked by 2 people

    1. Thanks for the comments. The Fenix 3 is still an excellent watch as I think it’s price is come down abit. It’s a media review for the watches unfortunately.

      Liked by 1 person

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