The Garmin Forerunner 235 is far from specifically designed for swimming, it is essentially a GPS running watch for outdoor use. However, a common new feature of most GPS watches these days is their waterproofing, in this case up to 50m. This means that it is perfectly protected to be used when swimming, or any other water based activity, meaning I gave it a try. I have also previously tried out the Garmin Vivosmart when swimming, but the results here were much more successful.
There is no specific swimming activity section like those seen in the triathlon watches and swim watches such as the Garmin Swim This meant that there would be no recording of specific ‘swim metrics’ data such as stroke rate and efficiency. Therefore, when using the 235 for swimming the best option would be the ‘other’ activity section. This can be used for any type of activity which is other than running and cycling – these are already pre programmed into the watch.
When swimming in open water, the watch can use the GPS capabilities and track your movement and distance. However, most likely, you will be swimming indoors in a lapped pool, therefore the GPS function will not work. As a result of this, the best option is to edit the data screens in the ‘Activity settings’ of the watch to display the number of laps (lengths) completed, alongside lap/ length time. This means that by knowing the length of the pool, the total elapsed distance would be easily calculated by also knowing the number of lengths you had done.
Each time a length is completed – in my case, 50m – the time for that length can be recorded by pressing the lap button. This is not the easiest manoeuvre as you have to break your stroke pattern to reach to your opposite wrist, however it doesn’t cause too many problems.
Open Water Swimming
Since initially writing this post, there has been a lot of good response on the open water swimming side. Since then, I have had some time to do some swims of my own where I have too been getting weird results regarding the distance tracking.
Garmin have a range of triathlon watches which are designed to be used in the sea of open lakes for outdoor swimming. The latest of these is the Forerunner 735XT which uses the internal accelerometer alongside the GPS to track stroke type in the specific Open Water Swim mode on the watch. This is different from the Forerunner 235 which has no Swim option, due to popular demand in the comments here is some extra information about the capabilities of the Forerunner 235 in open water.
When using the Forerunner 235 for open water swimming – or any other waterproofed GPS enabled watch for that matter – the main issue seen is inaccurate distances recorded whilst the route taken is often zig-zagging in nature and not in the straight path which the watch would always track on land.
This difference in GPS data when swimming is not due to the type of GPS hardware system (this is the same in all running and triathlon watches), but it is in fact a software based issue.
Garmin encode special algorithms for their triathlon watches for open water swimming where there are constant changes in GPS signal strength whilst the wrist is underwater. Therefore, these algorithms are capable of analysing and correcting for this when open water swimming.
This however is not written into the running specific (Forerunner 235) watches as they are not designed to be swam with. This is a shame as it makes the 235 not the best watch for swimming; yet it is understandable from Garmin’s standpoint as it separates their running and triathlon lines with these different capabilities.
One last quick tip to possibly try out when open water swimming would be to use a swim cap. The Forerunner 235 can be placed inside at the back of the cap (near the top of your neck) so that it is continuously near the surface whilst swimming. This will help avoid the losses in signal when the wrist is underwater.
This comes with some problems such as not being able to see any activity data in real time, however from personal use, this isn’t too key whilst swimming and also isn’t the easiest to view in mirkier water. Another consideration may also be the Forerunner falling out the back of the cap so make sure it is tightly fitted!
Another solution would be to swim in open water with a swim buoy which you can easily attach the watch to and would likely give much better results that when worn on the wrist.
Since writing this post, I have been contacted by some developers of apps which allow the Garmin Forerunner 235 to be used as a swim watch. One app in particular I have seen to be quite popular is called ‘Pool Swim’ and can be downloaded via ConnectIQ here:
The ‘Pool Swim’ App is available to download to your device here.
Unfortunately I have yet had the opportunity to try out this app on my Forerunner 235, but will be doing so soon and updating this post to share the results.
Analysing Swim Data
When swimming indoors however, the watch won’t record or display your path which is a potential downside, yet again this isn’t a functionality which the watch is designed for. I found that the best thing to do (as previously said) is use the number of lengths and the pool length to calculate the distance covered and manually input this into Garmin Connect afterwards. There is an easy edit tool on the individual workout page where you can edit the time and distance covered.
Another thing to note, is that you can edit the activity type on Garmin Connect for that workout. When you download it, it will come up as an ‘Other’ activity, here you can change it to swimming and subsequently view all metrics in terms of pool length and pace (min/ 100m) which is useful.
For swimming in open water where the distance tracked is mostly inaccurate but not always too far adrift; you have the edit option for this too. Just click on edit activity when in Garmin Connect and the distance can be correctly altered to the known distance.
Knowing the correct distance swam is not always easy as veering off course whilst swimming is an often result. However, if competing in a triathlon (Olympic swim distance is 1500m) you would know your distance exactly. Another option would be to track the route you roughly swam via MapMyRun.com and then add this distance in manually afterwards.
Heart Rate Data
Lastly, the FR235 introduced a wrist based heart rate monitor meaning the need to wear a chest strap is no longer a necessity for heart rate data. Therefore, this would imply that heart rate data from swimming could also be recorded. However, the accuracy of this is to be questioned and I have no current means of testing the accuracy. For me, I found that the heart rate which was recorded was slightly higher than resting level with no major rise or fall seen.
It is also worth noting here that Garmin have newly introduced a sspecific swimming heart rate strap which can be worn in triathlons and paired with the triathlon watches. This would be a much more accurate means of recording heart rate than from the watch and would be interesting to compare the two results.
Overall, the Forerunner 235 has shown that despite not being designed for swimming, it is perfectly capable of meeting many of the needs which most amateur and recreational swimmers may want. Swimming in open water would give the best results, but if you want something which is waterproof and capable of giving you your length times, then the 235 is more than a good enough option. This also means that for the average person who goes to the gym, runs, cycles and occasionally swims, the Forerunner 235 is the perfect all round GPS watch.
Feel free to ask any questions – thanks for reading!