Garmin Forerunner 235 Running Watch Review
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The Garmin Forerunner 235 is a very smart watch which can calculate your VO2 Max from its wrist-based heart rate monitor and can predict race times based on your training progress.
Sleep Tracking with the Garmin Forerunner 235
Historically, fitness trackers have some trouble telling when you're actually asleep. Naturally, there is a period of time between arming your watch and actually falling asleep, and for some, this may be quite a long time. However, the Garmin Forerunner 235 is smart enough to know when you fall asleep so you don't need to tell it! In the software when syncing the app with your watch, you will let it know your standard sleep and wake times. For most of us we have some sort of routine. But that is it. From here, we let the device take control.
Heart Rate Monitor Without Chest Strap
Having a wrist-based heart rate monitor on your watch is a fantastic feature. It's true that wearing a chest strap is more accurate, however, it can be uncomfortable to wear and can be annoying to pair it sometimes. Having the technology there on your wrist to track your heart rate all day long is great. Unfortunately, this does have an impact on the watch's battery life. But if you are sitting and there is less change in your heart rate data, it will start to take a reading less frequently. You can look at your screen and get a snapshot of the last 4 hours of data.
Why do we want heart rate monitoring?
Training with heart rate data has so many benefits. There are many benefits ranging from how hard you are training through to your rest and recovery. Many purists do not want or see a need to know this info, but if you are looking to take your training to the next level, it can give you some important data.
Heart Rate Data Accuracy
My first run for comparing the heart rate accuracy data was a 6.5k run. I compared the heart rate data from the Forerunner 235 with my trusted Fenix 3. The Fenix reported an average heart rate of 170 bpm while the Forerunner 235 reported 169 bpm.
The chart below shows the data as a graph with the Fenix in green and the Forerunner in red. As you can see, the data does not totally align.

Overall, however, the data matches pretty closely apart from a few places where something obviously goes wrong.

Garmin Connect Via the App
With Garmin products, you can only have one device set-up as an activity tracker, so I created a new account on an old phone. No problems with this process but when I wanted to log in to Garmin's website online to view the data you can only log in with email. No idea what I used here. I only have my connect name. Quick(ish) call to Garmin and they could help me out here. I thought I would share this in case someone else is stupid enough to do the same!
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Conclusion
As a watch that does everything, this really is an excellent device. Activity tracking, heart rate, and running all to the highest of quality. If you are after a fitness tracker read up on the other wearables we have reviewed. Or you may already be sold on the Garmin Forerunner 235.
