Garmin 910xtPosted on 3.27.12
In my last few ocean swims, I’ve been playing around with my new toy, a Garmin 910xt. It’s Garmin’s lastest GPS, said to be more geared towards open water swimmers, aka triathletes, as the product is still extremely useful for cycling and running. While still not the perfect swimmer’s watch, this one does have a few perks my last contraption did not. For starters, this watch is entirely waterproof, so you are encouraged to wear it on your wrist while swimming (my old watch was in a waterproof bag stuffed under my cap). This has the benefit of allowing the swimmer to view their current time, distance, and pace while they are in the water. The drawback is the size of the watch, which is pretty hefty, to the point where I notice it while swimming and on land, my wrist is immobilized.
The 910xt does offer one new feature that could be extremely useful: cadence, or stroke rate in swimmer speak. Of course, this is halved because the watch is only on one wrist, so my average of 38rpm is really 76 strokes per minute. This sounds fairly accurate for me, although upon further review it seems to only bounce between 30 and 45 (or 60 and 90), as shown in pink below.
This leads me to believe this is not a super accurate reporter of stroke rate, because I’m fairly consistent and never at either of those two extremes, except maybe 90 in a sprint. In the Garmin program to view metrics, there is no way to look at stroke rate v. pace, which is what I would find most interesting if there were more accurate values for stroke rate. However, in the program I prefer to view stats in, Ascent, you can create average lines through the data (these are bolded below). I did this for both stroke rate (pink) and pace (green). As you can see, they do follow each other to some extent, reinforcing what is commonly known, that higher speeds are associated with higher stroke rates (up to a certain point, of course, and only as long as you are pulling at least some water).
Overall, I’m pleased with the Garmin 910xt but there are some definite needs for improvement (ex: accuracy of pace, stroke rate, improvement of user interface, waterproof heart rate monitor). In using it in the pool (it tracks laps, pace, and stroke, albeit not highly accurately), I have also been satisfied, yet not impressed. I believe it can be an excellent tool for those training for triathlon, who need basic swimming metrics but tend to focus more on the bike and run. However, for those looking for an ideal training companion specifically for open water swimming at a high level, this is not it.