June 30, 2022

Suunto 3 Fitness Full Review

suunto 3 fitness

Note: For this review, Suunto and their PR Agency, Spike, kindly sent me a Suunto 3 Fitness. This has allowed me to fully test all the features and put the Suunto 3 Fitness through its paces so I can give the best informed review possible.

To quickly access different sections of this extensive review, click on the quick links below:


Suunto 3 Fitness

Suunto is a specialist sports watch company. They lead the way in endurance sports with watches built to last for hundreds of hours, suited to ultra-endurance athletes. Whilst running and diving have been previous focuses for the company, Suunto has now branched out and made investments in the wider smartwatch market with the Suunto 3 Fitness.

The 3 Fitness is different to almost all other Suunto watches. This watch takes a more minimalist, understated design away from the usual bold, hard look of Suunto’s other watches. Primarily, the Suunto 3 Fitness is an all-round fitness smartwatch offering accessible features of activity and sleep tracking, heart rate, multiple sports modes, smartphone connectivity and more. The smartphone connectivity is limited to receiving real-time notifications from your phone but at this point you are not able to go back and view them.

Whilst in-built GPS is lost alongside the high-end Movescount connectivity, the Suunto App replaces these with connective GPS and a new, improved way of viewing your collected data on the Suunto app. The optical heart rate sensor is also one big step up in this watch, building upon previous hardware and software to create one of the most accurate and responsive heart rate sensors I have tested.

Suunto is pushing a new real-time training guidance feature which suggests workouts based off your fitness and training level. Alongside this, there is a suggested 7-day training plan which updates over time; to see whether this is suitable advanced or merely a gimmick, I have tested the watch over a number of weeks collecting a plethora of data and information from the watch to best inform this review.

Unboxing and Set Up

Suunto 3 Fitness

The unboxing process is very simple and clean. You are instantly greeted with the watch with the documents hidden beneath – you even get a Suunto sticker!

Suunto 3 Fitness Suunto 3 Fitness Unboxing

The USB charging cable is very much like any other seen with modern fitness watches. It clips onto the left-hand side via a four-pin connection. Upon connecting the watch to a computer, you are prompted to create an account with MySuunto via this link here. You should next download the Suuntolink app to keep the watch up to date. It should be noted that unlike many other watches which sync via the charging cable, the Suunto 3 Fitness transfers data via the Suunto smartphone app.

Suuntolink Suuntolink

A non-vital step is registering your watch with MySuunto once you have registered and signed in. This is easily done by inputting the serial number of your 3 Fitness, which is on the back of the watch.


Upon registration, you can follow the on-screen instructions to finalise the set-up process by entering your personal details etc, then you are good to go.

Connecting to your Smartphone

Primarily, the Suunto 3 Fitness is used with and alongside the Suunto App. This is where the 3 Fitness syncs to, and, your health data is analysed.

How to connect the Suunto 3 Fitness to the Suunto App:

  1. Press the top-right button to scroll to the Settings. Press the middle-right button to select Settings.
  2. Scroll down to the Connectivity option and select.
  3. Firstly, in the Connectivity page, ensure that Airplane Mode is switched to ‘Off,’ and that Discovery is set to ‘On.’ Next, scroll to ‘Paired Devices,’ which will initially say ‘No Devices.’
  4. Open the Suunto App and log-in using the same details that you registered with Suunto online (or register via the app). In the top-left of the app there is a watch icon; tap this icon to bring up watch pairing.
  5. At this point, the app will recognise your Suunto 3 Fitness and you will be prompted to enter a ‘Passkey’ via the app to pair the watch.
  6. Enter the ‘Passkey,’ and you should hopefully be shown a connected screen on the app to confirm the process.

Suunto 3 Fitness Suunto 3 Fitness

Having problems connecting your Suunto 3 to the Suunto App? Don’t worry, you are not alone, I too had a few initial problems!

Connecting to the right app is important as this step caused me a few problems. Before realising that the Suunto 3 Fitness does not sync with Suunto’s primary Movescount service, I initially synced with the Movescount App instead of the Suunto App which led to the watch not syncing with the Suunto App until the Movescount App was fully disconnected and deleted. I found the Suunto connectivity troubleshooting page very useful, and if you continue to have troubles then follow the steps found here.

Once the boring part of registration and set-up is complete, you can finally get a real look at the watch itself!


Suunto 3 Fitness

I think for those who have experienced Suunto watches before, the look and feel of the Suunto 3 Fitness will be a completely new experience. Suunto have introduced a clean, chamfered bezel around the watch which has five buttons in total: two on the left and three on the right. Fitness watch enthusiasts may note that this design is somewhat similar to a number of other watches on the market, namely the Garmin Forerunner 645 and the Withings Steel HR.

Suunto 3 Fitness Buttons

For a fitness watch and given the capabilities of the 3 Fitness, the form factor is surprisingly small and slim. There is a slight protrusion on the back of the watch for the optical heart rate sensor but this is unnoticeable when wearing the watch.

Suunto 3 Fitness
A small, extruding bump for the optical heart-rate monitor is unnoticeable.

In a form factor comparison to other leading fitness watches, the Suunto 3 Fitness more than holds its own. The sleek design stands out but remains understated as a fitness watch allowing it to be worn on a variety of occasions without being out of place. In respects to one leading competitor – the Withings Steel HR – the Suunto 3 Fitness is slightly larger but includes a full colour screen, with addition GPS connectivity features.

Suunto 3 Fitness

The Suunto 3 Fitness comes in three different colours, each looking to give a trendy look to the watch, allowing it to be worn out as well as for exercising, meaning it never has to leave your wrist. The colours available are: ‘All Black,’ ‘Black,’ (the colour that I have been testing for this review) and ‘Gold.’

Activity Tracking

Nowadays, activity tracking is a guarantee on all smart watches. With no surprise, Suunto has implemented this right into the heart of the 3 Fitness. As many fitness watch/ activity tracker users will be used to, the main activity tracking data points collected are:

  • Steps
  • Calories
  • Sleep
  • Stress Recovery
  • Heart Rate – (See heart rate accuracy section)
  • Fitness Level

An interesting and different feature added to this list is stress recovery and is something that I will look a bit more at down below.

One feature missing, however, is a prompt tp get up and move due to inactivity. I have found this is a great way to keep reminded to get up and walk around every hour or so.

The only issue that I have found with much of this activity tracking data is that a lot of it remains unsaved and unrecorded onto digital platforms outside of the watch. Albeit steps etc can be viewed on the Suunto app, but this is limited to the app whilst resting heart rate and stress recovery data is merely shown in real-time on the watch and no where else. This is a shame I think as Suunto could make good use of this data for long term training analysis and I hope that this is something that they implement further down the line, especially with heart rate and stress recovery data.


The Suunto 3 Fitness automatically acts as a pedometer and counts the number of steps that you take each day via an internal accelerometer. Whilst testing the watch over a number of weeks – and comparing it to other activity trackers – I found that on the whole the 3 Fitness is a strong and accurate activity tracker and pedometer.

I found that on average the Suunto 3 Fitness tended to count a greater number of steps than the Garmin Forerunner 235 and an iPhone 7 whilst tracking simultaneously. This isn’t a problem as activity trackers are far from perfect and there is always going to be an inevitable +/- error of around 10%.

To view your current steps for the day, scroll down three pages from the watch’s home screen where you can view an overview of the week along with your average weekly steps by pressing the centre button.

Your daily movements and activities are all tracked continuously throughout the day and are then available to see in the Suunto app. Here, Suunto accumulates all the stored data on the watch, presenting a bar graph of your step counts for each day along with a rolling average.

Suunto steps


The estimation of burnt calories is a strange one. This is an interesting indicator as to how active you have been throughout the day and many use this alongside calorie intake values when training.

The Suunto 3 Fitness estimates the number of calories you have burnt throughout the day, as well as estimating the calories burnt during a workout.

To calculate the number of calories burnt, the watch uses a variety of data inputs that include your: age, weight, height and heart rate. This gives an overall estimation which is displayed on the watch alongside the number of steps, three pages down from the watch face, as well as in the same way on the Suunto app.

Suunto calories
Active calories combined with daily calories burnt.


suunto 3 fitness

A feature also contained in most activity trackers now is sleep tracking and Suunto have implemented this in the same way that many others have done.

Sleep tracking is not automatically turned on. Scroll down to the sleep tracking page and hold down the centre button to access shortcuts; from here you can turn on sleep tracking.

You will be prompted to input your usual sleep pattern; the time that you tend to go to sleep and wake up. The watch will do the rest. It will automatically try to detect once you are sleeping and when you wake up (usually done through resting heart rate and internal accelerometer movements).

suunto 3 fitness
Setting your sleep preferences

Each morning, the watch will give a brief summary of your nights sleep along with the length of time that you slept for. The 3 Fitness also syncs sleep data with the Suunto app but unfortunately there is no in-depth sleep tracking data to analyse the type of sleep, be it light or heavy etc., as is seen on more advanced trackers.

Stress Recovery

This is a new and different feature which is rarely seen upon other watches. What it essentially does is detect what state your body is in by tapping into 24×7 heart rate data. The watch will initially display what state your body is in and how long it has been in that state. The different states are: inactive, active, stressed and recovery.

By pressing the centre button it will take you to a page showing your ‘resources’ from the last 24 hours. By resources, Suunto means your body’s energy, so if you are moving, you will be using resources. These are shown by grey bars, whereas when you are recovering, these periods will be highlighted in green.

Personally, I quite like this feature as it gives you an instant insight into how your body is reacting to exercise. The downside, however, is the fact that this data is not stored and uploaded to the Suunto app or Sports Tracker; thus, you are unable to analyse how long it takes you to recover, nor look into how your fitness level (by diving into the recovery time) changes over time.

Fitness Level

suunto 3 fitness
VO2 Max Level on the Suunto 3 Fitness

Suunto have retained a feature on the 3 Fitness which tends to be reserved for higher level watches. This feature which Suunto brand as ‘Fitness Level’ is an estimation of your VO2 Max level which is an overall indication of fitness level.

What is VO2 Max?

“VO2 max is the maximum rate of oxygen consumption measured during exercise of increasing intensity – Wikipedia”

This level tends to rise over time as you becoming fitter but plateaus when you reach a higher fitness level. The 3 Fitness does a number of internal calculations from the data it collects about your body and fitness level. Taking in the heart rate data from your recorded exercises, it is able to predict your fitness level.

It is important to remember that this is sole an estimate and not a certain value which can only be attained from an official test measuring your oxygen consumption during exercise. Nevertheless, it is a cool value to have access to to give an idea of how fit you are.

Sport Modes

Suunto 3 fitness exercise

Whilst the Suunto 3 Fitness is a more accessible, cheaper and less advanced watch as previous Suunto products, Suunto have included a whole host of exercise features.

The 3 Fitness is similar in many ways to other Suunto watches such as the Spartan series but lacks the built-in GPS. Here, the 3 Fitness has a range of sports to choose, with those which require GPS having the ability to connect via the smartphone app.

From table tennis to Football, from indoor training to indoor swimming. The Suunto 3 will almost certainly have a designated sport mode for you. So, let’s get started!

To start exercising with the Suunto 3 Fitness, press the upper-right button once to scroll to the Exercise page. From here, you are initally met by one of the smart training sessions suggested by the ‘Adaptive Training Guidance,’ an innovative feature added here by Suunto and something I will look more at below.

Aside from the Adaptive Training Guidance, scroll down through the variety of sport modes available, selecting your chosen sport. From here, each of these sport modes has individual settings that are just customisable in the options page. For those which track your movement, e.g. pace, distance etc., you will have the option of connecting to the Suunto app for connected GPS via your smartphone, or use the internal accelerometer.

For this review, I am going to take a closer look at the most commonly used sport modes: swimming, cycling and running.


The Suunto 3 Fitness is water resistant up to 30m. This means that you can be more than confident submerging the watch for showering and swimming, both in pools and open water.

The 3 Fitness has two different swimming modes. The most commonly used mode will be ‘Pool Swimming’ mode, but Suunto have covered all bases here and offer an ‘Open water Swimming’ mode.

For pool swimming, the watch should firstly be set up with the correct pool length. Initially, the watch is set to 25m, but this is customisable for any length pool at 1m intervals which is a nice feature to encompass all pools.

An interesting thing to note at this point is the fact that Suunto have kept optical heart rate tracking for swimming which is known to lack accuracy due to water interference. Unfortunately I haven’t had the opportunity to compare the accuracy to a more reliable swim-based heart rate monitor such as the Garmin HRM-Swim. It is also not possible to connect the Suunto 3 Fitness to alternative sensors as it lacks ANT+ connectivity features which is a shame.

Once you have started the watch in the pool, the Suunto 3 Fitness will record your swim pace (min/100m) and distance swam.

For open water swimming, there is a interesting option. Suunto allow you to pair the watch with a phone to track the swimming via connected GPS. This is a strange option given most people are unlikely to want to swim with their phone, even if it is water resistant. Despite this strange option, you are still able to swim without connected GPS, using the internal accelerometer, however I suspect the level of accuracy here is going to be suspect. I haven’t been able to test the watch in open water yet, but if I do get the opportunity I will update the post.


Cycling with the Suunto 3 Fitness

Cycling with the Suunto 3 Fitness is very easy and accurate but lacks higher-end capabilities. As with running, you can track your cycling either by the internal accelerometer or by connected GPS with your phone. I have tested out the cycling features of the 3 Fitness with connected GPS and found no issues at all.

Cycling data as displayed on the Suunto app

The watch displays your speed in along with heart rate, time and distance. So, despite this being of a fairly basic functionality level, it nevertheless does the job. You cannot link the watch to fancy power meters or other sensors, but for any beginner it is good enough.


suunto 3 fitness
Running on the 3 Fitness

Running will undoubtedly be one of the most commonly recorded activities on the Suunto 3 Fitness. Because I predominantly focus upon running here on Run Reporter, I have decided to do a specific, more in-depth review of running with the 3 Fitness, you can read this post here.

Running on the 3 Fitness can be recorded in a number of ways. There is a general ‘Running’ sport mode, a ‘Track and field’ mode and a ‘Treadmill’ mode for running indoors. There is no discernible difference between the ‘Running’ and ‘Track and field’ modes other than the name, they both record your activity in the same way.

Before getting started with running, there are a few settings which may be of use to customise. Firstly, there are targets. In the targets sections, you can add an intensity target based off heart rate zone, or a general duration/ distance target.

stunt 3 fitness

There are also specific intervals which can be set up on the watch. These intervals can be set for a specific duration/ distance as can the recovery, you then just have to choose the number of repetitions. Albeit slightly simple without the ability of sending specific training sessions to the watch, the Suunto 3 Fitness does offer a sound interval option which can be well-utilised by those on set training plans.

stunt 3 fitness

suunto 3 fitness
Intervals on the 3 Fitness

Once all configured, you press the centre button to start. The watch has four different data screens. Heart rate, distance, pace, heart rate graph. With each page, the cumulative time appears at the bottom of the screen.

I think having the heart rate graph data screen is great idea. Given the high-level heart rate sensor, it is quick to react to changes in heart rate which are then displayed not he graph for the last few minutes or so. This gives a good impression as to how hard you are working and how quickly you are recovering, especially on interval sessions.

Unfortunately, there is no customisation possible here, you are stuck with the data displayed. For example, it would be nice to view current lap time to help with interval training. On the note of lapping, to create a lap, press the bottom-right button. The watch also automatically laps either every mile or kilometre, depending on whether you have set the watch up in imperial or metric mode. This is also something which cannot seemed to be turned off on the watch or neither changed from imperial to metric, or vice versa.

To finish a run, you press the upper-right button. This allows you to then rate the run and view the stats.

Suunto 3 fitess
Post run stats
suunto 3 fitness heart rate
Heart rate zone page

The last thing that I am going to look at on the running side is the connected GPS accuracy. With connected GPS, there are a number of factors which determine the accuracy. The in-built GPS on your smartphone is one factor, but it is also the way in which the app utilises the phone’s GPS which results in higher accuracy levels. This means that you could record a run on multiple different apps on the same phone but get different results.

With the connected GPS, the accuracy on the whole was never quite perfect. It almost always tended to overestimate the distance run and therefore the pace too was faster than it should have been. When comparing the GPS results after the run, it is easy to see why this is.

The GPS track from the Suunto app is noticeably jagged. Instead of a smooth track, the GPS tracked route jumps around from each data point to the next meaning overestimates the distance, by adding more than it should. In comparison to this, on the Forerunner 235 for example – which uses GPS+GLONASS technology at 1 second intervals – the tracking is smooth and reliable as seen below.

Smooth tracking on the Garmin Forerunner 235
Jagged GPS track on the Suunto 3 Fitness using connected GPS

This is also evident on another run between the two watches when looking at the pace analysis. On the Suunto watch, pace seems to be very inconsistent, with multiple ‘drop outs’ in the data. This is compared to a much more consistent pace seen on a watch with in-built GPS.

Garmin Forerunner 235 pace analysis
Suunto 3 Fitness pace analysis

Despite these inaccuracies, the data only tended to be skewed by about 2-3%. This sounds small but across, say an 8 mile run, this gives an additional 240m which is quite a large difference in running terms. It may not be wholly accurate, but given built-in GPS isn’t available then it is as good as one could hope for and nevertheless does the job for someone new to the sport.

The lack of in-built GPS which comes as a strange omission on a £150+ smartwatch but is what had to give to create such a sleek entry-level smartwatch. It appeals to beginners, not the high-end athlete.

Adaptive Training Guidance

suunto 3 fitness

The Adaptive Training Guidance is a new and great feature added to the Suunto 3 Fitness. As I have already discussed, the 3 Fitness is aimed at new, beginner athletes, and the Adaptive Training Guidance is perfect for this type of athlete. The idea of the guidance is to create a training plan based off current fitness level and activity level.

The Suunto 3 Fitness has a  specific ‘Training’ page that you can scroll down to from the home screen. Here, you are met with your cumulative training time for he week so far compared to your weekly training goal that you can set via the Suunto app. By pressing the centre-right button, you are taken to your weekly training programme where you can view the individual training sessions.

As the name suggests, this training plan is not fixed and is adaptive to your weekly routine. If you do additional exercise or miss a day, the guidance adjusts and updates the training plan.

One of the nice things about this training plan is that it is not specific to any sport. Each session has two aspects to it: the length of time and the intensity at which the session should be performed at. The intensity levels is in accordance to the heart rate zones that you should be working in, ranging from easy to very hard. As the sessions are designed to raise your heart rate, you can adapt the training yourself to be in the pool, running, walking or what ever sport you want.

suunto 3 fitness
Intensity level description of an Adaptive Training Guidance session

Heart Rate Sensor

suunto 3 fitness
Suunto 3 Fitness Heart Rate Monitor

The quality of optical heart rate sensors over the last few years has been increasing manifold. One of the biggest difficulties faced by optical heart rate manufacturers has been the rate at which the heart rate sensors can pick up and measure quick changes in heart rate as often seen in interval training. This is something which I believe Suunto have done a great job on with their heart rate sensor.

The optical heart rate sensor in the 3 Fitness is provided by Valencell, a known industry expert who provides sensors for multiple other companies. Suunto have managed to implement this alongside their software to great effect.

suunto 3 fitness

Over my time testing the optical heart rate sensor on a variety of occasions, I have bene very impressed, especially on short, hard intervals. Unfortunately, as I previously talked about, Suunto have not made this data easily accessible. You cannot export it properly to be analysed and the presentation of the data on the Suunto app or Sports Tracker is very limited. Despite this, it is still possible to get an idea for the responsiveness and accuracy of the heart rate data.

suunto 3 fitness

Firstly, looking at the heart rate data on a simple 4 mile run. The heart rate steadily increases over time, remaining at a steady rate without any drop outs or anomalies throughout. During the run, there were one or two instances where I had to stop and cross the road. This is indicated on the top line where the speed drops off. What is encouraging to note is the instant drop-off in heart rate at the same instance, picking up the change in work rate before steadily increasing again.

Pace analysis for 4x800m session, last 200m faster
Heart rate data for 4x800m session

This heart rate data from a hard interval session is most encouraging, more so than a continuous steady run. We can see here how the heart rate data quickly increases and decreases at start and end of each rep, steadily increasing throughout the rep, peaking towards the end as the pace is pushed.

To compare the accuracy and data, I compared it to the Garmin Forerunner 235 which has an older and less reliable/ accurate sensor. Here, I saw much better data being collected on the Suunto 3 Fitness.

Pace vs heart rate as recorded on the Forerunner 235

As you can see, the Forerunner really struggled on the first few reps to read the correct HR level during the rep which was around 180+ BPM. The peak recorded on the final rep once it had fixed onto the reading was 184 BPM.

Suunto 3 Fitness HR data

Comparing the previous Garmin data with that of the Suunto watch, we can see the 3 Fitness much more accurately tracks the heart rate from the beginning to the end of the 1km rep, reacting much quicker than that of the Garmin. What is also interesting to see on the three sprints done at the end of the session is that the Suunto picked up a much higher HR reading (170) than the Garmin (140).

Overall, I am very pleased with what Suunto have done with the optical heart rate monitor, matching and surpassing that of the TomTom Spark 3 that I tested last year. It is very quick to react to changes in heart rate level and maintains steady and accurate tracking as good as anything else I have tested.

Suunto App and Sports Tracker

suunto sports tracker
Sports Tracker

Throughout this review, I have often referred to the Suunto app and Sports Tracker. These are the only two ways that you are able to view your data collected on the Suunto 3 Fitness. Traditionally, Suunto’s watches connected to their Movescount platform, however this is not the case with the 3 Fitness for unbeknown reasons; it seems as though Suunto is making a concerted effort towards a comprehensive mobile platform along with one centralised platform.

It is also not possible to pair the Suunto 3 Fitness with other third-party platforms such as Strava. Now this is really is a strange one for me as it limits the level at which you are able to track and view your data – but that may just be of greater interest to keener people like myself rather than the general user!

Suunto bought the Sports Tracker platform a few years ago and have built their new app around this existing platform, making the two very interchangable. Although there is a Sports Tracker app, it is best to use the Suunto app alongside the Sports Tracker online platform which provides a little more flexibility when it comes to view the data such as with better graphs etc.

The main sections of both the app and Sports Tracker are:

  • Feed/ Dashboard
  • Diary
  • Leaderboard/ People
  • Map/ Routes

The feed and diary are very self explanatory and provide a view of all pasta workouts in a chronological order.

When you go into an activity on the app, you are met with a whole host of information, ranging from a map, to the heart rate graphs to the splits.

Suunto app layout

All of the same data which is available on the app is also available on Sports Tracker, but Sports Tracker tends to be the better option for analysis the graphs as they are displayed much larger and are interactive.

One of my favourite features of the app and Sports Tracker is the ability to create routes right on the app. Very much like how MapMyRun works, there is an interactive map which has auto-follow routes that allow you to map out a route which tells you the distance. You are then able to save the route. Sadly there is no ability to send the route to the watch to then be followed, but I am sure this is something which may be possible further down the line.

Creating a route on Suunto

Suunto 3 Fitness Conclusion

suunto 3 fitness

The Suunto 3 Fitness is an all-round fitness smartwatch. It takes the appearance of a sleek, everyday watch whilst packing in a tonne of features from advanced activity tracking to a range of sport modes to appeal to anyone. On top of all of this, Suunto have implemented in one of the most accurate and impressive heart rate monitors. This heart rate monitor has allowed Suunto to create Adaptive Training Guidance with specific heart rate sessions that wouldn’t have been possible otherwise.

Now this is not going to be the watch for everyone. Although there are a lot of features, they are all at a baseline level. The watch lacks the high-end features seen on other fitness watches but that is understandable as Suunto have targeted the wider market with a fashionable activity tracker with decent sport tracking capabilities despite the lack of built-in GPS.

So if you’re a high-level athlete then this won’t be the watch for you. But if you are keen on your fitness and want a solid activity tracker with an amazing heart rate sensor and stylish design, then the Suunto 3 Fitness is for you.

Thanks for reading!

To help support this blog and to help me continue providing in-depth reviews, use the links below.


  1. Thanks very much to you share the Suunto 3 Fitness. Can you please say me if i can import GPX files to Suunto 3 fitness and if it works well for trail? Thanks again.

Leave a Reply

Your email address will not be published.