I’m training for the Copenhagen Marathon in May of this year (2015), and have been using Strava and a new Fitbit Surge device to track my runs. Unfortunately the two systems are not compatible (yet), and I can’t use the heart-rate readings from the Fitbit Surge as health data inside the surge app. I just completed a 15m training run and I thought I would post the side by side data that the two apps gathered in hopes this might be of use to other runners considering using either of these two systems.
- The GPS tracking of the Strava, which is running on my iPhone 6, is much more accurate than the location readings on the Fitbit Surge. The Strava/iPhone readings are really precise and show small variations in my 4 laps around the lake. The Fitbit Surge GPS is almost comically “loose”, suggesting a meandering variation on each lap, sometimes straying into the lake itself or across non-existent streets.
- The splits/pace information is pretty consistent. I tried to start both devices tracking at the same time, but the differences in the splits and the total distance and time of the run may be as a result of slight differences in start time, and, when I paused for a 40 second water break mid-way i manually paused the fitbit clock, but the Strava was on auto-pause and may have taken a different sense of that timeframe. That would account for the 2:05:08 (fitbit) v 2:05:34 (strava).
- No idea how to rationalize the 15.01m Fitbit distance vrs. the 15.3m for Strava, which results in the pace discrepancy: Ftibit says i had a 8:20 overall pace, Strava 8:13 pace.
My sincere desire is that Strava and Fitbit will get their systems connected, not sure who has the burden to do what work, but certainly can’t be very far from core to their missions to support as many devices/APIs as possible in this connected health tracking wearable category? Strava is focussed on community, Fitbit on devices–let’s go guys!
Later update (March 10 2015): I’ve continued to run 4-5 times per week using both Fitbit Surge and Strava and can add some new data:
- The Fitbit Surge is VERY inaccurate in terms of distance travelled on a run, whether that be a 3 mile or a 21 mile course, on road/path or on a treadmill. I’ve seen a consistent 15-20% under-report of distance run in both free-run (GPS tracking on) mode and “treadmill” run mode. In Treadmill mode the distance travelled is under-reported almost comically–the device is just pretty much worthless in accuracy on a treadmill. I would think that the device’s software could compare my GPS enabled and not-enabled runs and correct itself to a better estimate of my gait/pace based on the other data its sensors are gathering. Alas, the software is clearly NOT doing that kind of comparison of the data and optimization to individual user performance.
- The Fitbit Surge is VERY inaccurate in terms of geo-location in GPS mode, and as a result, the pace readings during a run are absurd as well. While running at a 8:15 minutes per mile pace the surge will report anything in a range of 7:45 to 9:30–ostensibly because it has no idea where i am physically on a map. The readings that come back from my runs are hilarious–showing me running through buildings, into lakes, etc.–yes, it is approximately correct, but nowhere near accurate enough to track distance and therefore useless for pace and overall splits.
- While i have no second heart rate monitor tool to compare the readings to, i’m also confident that the hear rate readings are wildly inaccurate, as during a long run where i’m in a steady state zone of pace/energy/effort, the heart rate readings will ramp up and down by 10% range which is attributable to inaccuracy of the device’s readings, not variations in my heart rate load.
Here is a recent run that Strava reported as 21.1 miles, side by side with Fitbit. Notice the accuracy of tracking on Fitbit Surge leaves much to be desired–which makes the device pretty useless as a serious fitness device:
Give my first 2 months of experience with the Fitbit Surge, i would not recommend as a health tracker–way too inaccurate. I’m actually now very curious about the Apple Watch which is shipping soon, given that it will rely on the phone for measurements which i’ve found to be much more accurate (via Strava).
I’ll add to this post if I learn more.