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Fitness
- GPS can be slow to lock on
- Heart rate monitor is accurate
- Heart rate monitor can also tell you your performance condition
Right - let’s get onto the real reason you’re here: to find out how good this watch is for tracking running, biking and pretty much anything you want to throw at it.
One of the things that surprised us about the Garmin Forerunner 935 in terms of performance was the slow lock of the GPS signal - it’s one of the worst we’ve seen from the recent Garmin range.
It’s not terrible by any means, but most of the watches we test from Garmin either lock on within seconds or learn where they are well and pick it up quickly the next time.
The Forerunner 935 can leave you waiting for thirty seconds to a minute fairly regularly - it’s not that long and easy to manage, and sometimes it’s rapid, but we did have too many instances of being left out waiting in the rain and cold, and we expected better from a watch of this standard.
The heart rate monitor (HRM) is pretty darn accurate though - we found ourselves dropping the chest strap more often than not, as the wrist-based data was actually accurate enough to make decisions about how hard we were going and seemed to correlate well with actual raises and drops of intensity.
That HRM packs in some other decent tech too: performance condition. This watch can monitor how hard you’re working and correlate that with your heart rate variance, which is the difference between each heartbeat.
As you get more tired, your pulse becomes more uniform and the watch can tell you that in real time, giving you a literal number that explains how much effort you’ve got left in the system.
This can be a blessing and a curse: the days when you start running and you’re told your condition is ‘+4’ means you can go out and have a nice run, with loads of energy to burn.
However, start with a negative number and you’ll worry that you’re not going to have a decent time, especially at the start of a race.
Then again, knowing that you’re in ‘energy deficit’ is nothing more than a fact, and if you can run accordingly, giving yourself a breather or putting in more effort, you’ll have a nicer time overall by not pushing too hard and blowing up or leaving anything in the tank unnecessarily.
Running
- One of the more accurate running watches
- Lots of data available on customizable screens
- Can alert you to whether you're above or below the pace
The run tracking on the Garmin Forerunner 935 is excellent. It’s really hard to actually fault it, as it does everything you want it to do and more.
For most of us, the main thing you want is just something that can show you the data you want - and there’s very little here that the 935 couldn’t pump out. Even if you’re a fairly elite-level runner, you’ll see some functionality in here that you’ll think is a bit above your station.
You can customize loads of screens, which you can cycle through with the up and down arrows easily, and see everything from pace, to time, to monitoring which foot is more dominant (with the chest strap or optional foot pod), to the time the sun is going to come up.
You can also set interval sessions from the watch itself, or create a dedicated workout in the Garmin Connect app on your phone and have it sent to the watch.
This is a really neat feature, as it means you can create structured training sessions (say, you want to do an interval session of longer and longer sections with rests in between over 10 miles at varying paces) and then just start them on the watch and let it be your coach.
When you’re putting in high effort, the thought of ‘am I running fast enough?’ isn’t one you want - and this watch will bleep to let you know if you’re above or below the pace.
It can do the same with heart rate as well, which is really useful if you’re looking to train smarter - and trusting in the wrist-based HRM makes it a cinch to just tap a few buttons and go.
We’ve used the Forerunner 935 in a number of races, including multiple marathons, and it’s generally one of the more accurate over long distances. Like most watches it’ll get a bit thrown out by high buildings or trees, but over the run we found it to be one of the more accurate options.
Our model did recently suffer a fatal freeze in the middle of a marathon, which was upsetting, but that was after many months of use and is quite anomalous according to a web search.
There’s a fairly robust buzz from this watch as well, which means if you’re looking to get an update on how fast you’re running each mile or kilometer the alerts are easy to feel, which isn’t always the case as some watch manufacturers make the vibration engine smaller to make the device more compact.
Cycling
- Displays speed and cadence accurately and visibly
- Can easily transition between triathlon stages
- Can connect to a huge number of sensors
One of the best parts of the Garmin Forerunner 935 is that it’s capable of doing so much and tracking it accurately. With running, cycling, swimming, paddle boarding and even ‘Jumpmaster’ on offer, you can easily track yourself through most races.
Cycling is a big part of the triathlon scene, and while one might not want to have to keep checking their watch when cycling to see how they’re getting on - many will have a cycling computer for that - the ability to transition easily between stages is useful.
(There is a dedicated triathlon mode, but you can also join your own sets of activities together and create things like a duathlon with ease).
What impressed us most about the cycling mode on the 935 was the sheer range of sensors you can connect. Like running, there’s little to say about the capabilities of this watch with regards to cycling because it’s easily capable of displaying your speeds and distance accurately and visibly on the screen.
Take it further though, and you can connect lights, power meters and even cameras to the watch, firing them right from your wrist.
The Forerunner 935 is a good pal when inside on a static trainer too. We connected the watch to an expensive bike (a Planet X ex130e with Shimano 6870 di2 groupset) in a front room, where it sat on a TacX Satori Smart turbo trainer, which in turn connects to the PC under a TV to ride in the Zwift virtual world.
When we go to connect the watch to the turbo trainer, the number of sensors we can use is dizzying, including power, cadence and a whole range of other metrics.
After cycling in the Zwift mode, all our information from the ride was instantly logged in the Garmin app so we could see stats, and they were uploaded straight to Strava too.
Swimming
- Not super accurate in the water
- Can auto-detect stroke types
- Lets you set drills and buzzes to tell you when to change things up
Even if you’re not a great swimmer, having a watch by your side can be really useful for post-workout analysis.
You can’t do much with the Forerunner 935 while you’re splashing away in a pool (apart from monitor the amount of lengths you’ve managed, which it’s not terribly accurate at, often missing a length at least in most sessions), and if you’re in anything smaller than 17 meters long then the Garmin can’t track you - so be warned, you’ll need to train somewhere properly.
It’s also capable of tracking outdoor swims, using the GPS, and while this could be a little shaky (we weren’t able to test in anything exposed to the sky) because the watch is plunging underwater so often and losing signal, if it’s anything like the others in the Garmin range we expect the 935 to be pretty good in the outdoor lakes of this world.
The Forerunner 935 is definitely a capable swim watch - you can set drills to know when you’re pushing and not, it can accurately tell you which stroke you’ve been doing in the post-swim debrief on the Garmin Connect app and can even monitor SWOLF, which is an amalgamation of stroke rate and time taken, to help give you an indication of how hard you’re working.
If you are doing drills, while you’re not going to be able to look at the watch mid-length, the haptic buzzing is really great underwater, making it easy to know when to change things up.
We weren’t enamored with the accuracy of the 935 in the pool, as the missed lengths were irritating, and it can’t tell you your heart rate from the wrist in this scenario, but the ability to know which stroke you were doing automatically and uploading all the info to Strava is really cool.
Strength and HIIT workouts
- Inaccurate rep counting
- Basic HIIT support
A more recent update to the Forerunner 935 is the addition of strength training, where it can monitor reps of what you’re doing in the gym while you lift heavy pieces of metal while glistening.
It’s pretty fully-featured too, with loads of exercises to choose in the Garmin Connect app, and you’re able to send them to the watch and have it tell you what to do for each set.
In theory it’s supposed to count how many, and you input in the weight (either in the app or on the watch) to record how well you’ve done.
It really doesn’t work well. The rep counting is often wildly inaccurate even if you lift ‘not too fast, not too slow’ as Garmin suggests, and the information on what you’re supposed to be doing in each set is very fleeting too, with no way to recall it.
It’s good that it suggests you do a warm up before you start, but it doesn’t go into depth about how you should do said thing - would it be too hard to just suggest some basic arm swings or similar to help a newbie get going?
We did find that some moves - like bench pressing, for instance - were easier to track than others, with things like pull-ups obviously being hard to track.
In short, the rep counting has far too many issues, but as a way to structure a workout, it’s pretty good. In Free Workout mode you get a rest timer too, so you can track how long you’re letting your body recover, so that’s useful.
Would we use this again for gym workouts? Only if we had a really technical workout and needed guidance throughout… but even then, we’d like to be able to remind ourselves how many reps or what weight we’ll need.
High intensity interval training (HIIT) is also supported on the 935, but only through the ‘Cardio’ app, which basically just tracks calorie burn. Yes, you can download others through the Garmin Connect IQ store (more on that soon) and we tried something called WorkItOut.
It was… fine. Star jumps, wall sits, planks were all there but nothing that really taxed, and the heart rate monitoring seemed rather inaccurate.
The Apple Watch range is now adept at monitoring your HIIT efforts, based on a smarter understanding of calorie burn in these scenarios, and we’d have expected Garmin to follow suit.
