This weekend, I ran a 20-mile marathon coaching race sporting 4 health watches — the Garmin Fenix 8, COROS PACE Professional, Apple Watch Extremely 2, and Google Pixel Watch 3. I felt like a weirdo, but it surely was really a extremely helpful alternative to test which metrics are most constant throughout manufacturers — and that are almost definitely to be unsuitable or random.
I normally put on two smartwatches at any given time throughout runs, and I as soon as wore six watches for a step-counting take a look at. Often, I am on quiet trails the place my absurd tech habits do not entice a lot consideration, however I knew that would not apply in the course of the Run the Parkway race, which had almost 1,000 runners.
Fortunately, the mid-40ºF climate let me put on lengthy sleeves, hiding my foolish look at first. But it surely began warming up, and my sleeves began activating some watches’ touchscreens and messing issues up. So I rolled them again and noticed spectators and runners alike glancing confusedly at my wrist-laden arms.
No matter they considered my weird look, I bought some nice information out of the 20-mile race, summarized within the desk under!
| Class | Apple Watch Extremely 2 | COROS PACE Professional | Garmin Fenix 8 | Google Pixel Watch 3 |
|---|---|---|---|---|
| Distance | 19.92 miles | 20.11 miles | 20.08 miles | 20.19 miles |
| Tempo | 9:38/mile | 9:33/mile | 9:34/mile | 9:31/mile |
| Ascent | 675 toes | 709 toes | 676 toes | 680 toes |
| Avg. / max coronary heart price | 168 bpm / 179 bpm | 168 bpm / 182 bpm | 168 bpm / 182 bpm | 167 bpm / 181 bpm |
| Operating energy | 250 W | 264 W | 351 W | Unknown |
| Energy | 3,016 kcal | 3,332 kcal | 2,773 kcal | 3,190 kcal |
| Coaching load | Unknown | 781 | 362 | 565 |
| Steps | 31,958 | 32,247 | 32,196 | 32,192 |
| Cadence | 162 spm | 163 spm | 162 spm | 162 spm |
| Stride size | 1.02m | 1.03m | 1.03m | 1.03m |
| Vertical oscillation | 9cm | Unknown | 8.6cm | 7.7cm |
I completed the primary 13.1 miles at a strong 1:55:31, or 8:49 tempo, however my muscle soreness made me walk-jog the final 5 miles within the 11/12-minute vary, skewing my working type stats. However I am nonetheless usually pleased with the outcomes as I return to marathon form for 2025!
Notice: My Apple Watch Extremely 2 randomly stopped my exercise by itself as a result of random touchscreen inputs from my sleeve. I fortunately seen it rapidly and began a brand new exercise, however had so as to add up and common information from 4.5-mile and 15.4-mile actions, and the ultimate distance most likely would have been above 20 miles if not for this snafu.
Constant information throughout manufacturers
That Apple exercise glitch apart, all 4 watches have been fairly shut in complete distance and tempo and have been principally in lockstep in areas like common coronary heart price, steps, cadence, and stride size.
Regardless of their totally different HR algorithms, accelerometer tech, and positions on my arms, they almost matched when calculating how far and infrequently I stepped — and the way arduous I used to be pushing myself — throughout three hours. That is spectacular!
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When it comes to distance, I instantly seen that the GPS-only Pixel Watch 3 buzzed my wrist that I might completed my first mile nicely earlier than the others, then fell right into a constant sample of marking every completed mile about 0.1 miles earlier than every mile marker. Regardless of the dearth of sign blockage on my route, a GPS-only watch is barely satisfactory at one of the best of instances in comparison with the dual-band outcomes of my different three watches.
I already wrote concerning the COROS PACE Professional’s GPS accuracy in comparison with the Fenix 8, and that held true right here: Just like the Pixel Watch 3, it marked me ending my first mile earlier than the Fenix 8, however then it held the identical place for each subsequent mile, beeping about 10 working strides earlier than the Fenix 8 all the way in which to the end.
For elevation information, Apple, Garmin, and Fitbit have been all inside 5 toes of each other, whereas COROS barely overestimated my effort. The PACE 3 did higher in my previous elevation accuracy take a look at, so I am curious if the PACE Professional altimeter wants some tinkering. In any other case, I’ve discovered virtually any watch with an altimeter provides fairly constant ascent information.
As for HR accuracy, I paired my COROS HR armband to the Tempo Professional for a baseline in opposition to the opposite three watches, and the outcomes have been predictable: the Fenix 8 is wonderful for optical HR accuracy, whereas the Pixel Watch 3 is regular however tends to fall just a little brief for anaerobic coronary heart charges. The Apple Watch Extremely 2 additionally appeared to do nicely on common however fell a couple of beats wanting my max HR.
The place health watch information diverges
Contemplating how constant the outcomes have been in some areas, it is a bit shocking how totally different the 4 watches’ outcomes have been in different areas:
Operating energy: A few of the finest health watches calculate the vitality put into your run primarily based on components like velocity, cadence, stride size, and vertical oscillation so you may decide your stride’s effectivity and your total effort. You’d suppose my working energy information would have been nearer throughout manufacturers. As an alternative, Garmin put my effort about 100W increased than the opposite two that tracked that information.
I do know quite a lot of runners and specialists put inventory in utilizing working energy as a substitute of tempo to find out how nicely or quick they’re working, particularly on hilly or windy programs. However I’ve seen this variation in working energy throughout manufacturers earlier than, and if they can not agree on my wattage for a flat and non-windy course, it makes me leery of utilizing this metric as my benchmark whereas working. It is one thing I need to attempt to take a look at extra sooner or later.
Coaching load: TL is extra of a proprietary information level, even when all of them use some type of the coaching impulse (TRIMP) technique. So, I am not stunned that manufacturers differ in how they calculate it. But it surely’s nonetheless fascinating to see COROS give me greater than double the coaching load Garmin does with near-identical stats, with Fitbit’s Cardio Load falling squarely within the center. (Apple’s TL is all about charts relative to previous weeks and does not put a quantity on exercises.)
For what it is value, I’ve seen previously that Garmin generally is a bit conservative with its coaching load estimates (particularly for lengthy hikes) and is not excellent at splitting low/excessive cardio and anaerobic masses for one exercise. In the meantime, COROS provides out TL like sweet on Halloween, overestimating my effort. On this case, I believe Fitbit’s TL would possibly win the Goldilocks “excellent” award right here.
Energy: That is one other health metric I have been side-eyeing for a while. After any exercise the place I put on two watches from totally different manufacturers, the ultimate burned-calorie rely is totally different, regardless of how comparable the mileage and HR totals are.
This 20-miler solely made the variations even starker, with a 500kcal hole between COROS and Garmin. However you will nonetheless discover a distinction for shorter runs or walks, whichever health watch you purchase. And anybody making an attempt to drop some pounds or choose their caloric want for the day will make very totally different life selections primarily based on this information.
I might love to determine which model is most correct for caloric burn. However in contrast to after I’m testing GPS routes in opposition to satellite tv for pc maps or coronary heart price in opposition to arm or chest straps, I do not know of any manner a layman can take a look at the outcomes outdoors of a lab.
Discovering a working watch you may belief is necessary
This expertise taught me two issues. One, do not inform your boss, “Hey, I am working a race this weekend; is there something I ought to take a look at?” It will solely result in embarrassment and spending hours the day earlier than charging all of your watches. Two, working watches are getting higher and extra dependable for uncooked information than ever, matching one another throughout manufacturers in ways in which rely.
Garmin remains to be my most popular working model as a result of I have been utilizing its coaching load, recommended exercises, and restoration information for years, and quite a lot of runners belief its accuracy. However checks like this make it plain that different manufacturers might be trusted too, at the very least on the {hardware} facet. And even when watches just like the Apple Watch Extremely 2 and Pixel Watch 3 are extra for “informal” athletes by way of software program, they’re getting higher and higher yearly.
