This weekend, I ran a 20-mile marathon coaching race carrying 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 probably to be improper 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 test. Often, I am on quiet trails the place my absurd tech habits do not appeal to a lot consideration, however I knew that would not apply throughout 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. Nevertheless it 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 received some nice knowledge 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 fee | 168 bpm / 179 bpm | 168 bpm / 182 bpm | 168 bpm / 182 bpm | 167 bpm / 181 bpm |
| Working 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 stable 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 operating type stats. However I am nonetheless typically proud of the outcomes as I return to marathon form for 2025!
Be aware: My Apple Watch Ultra 2 randomly stopped my exercise by itself as a consequence 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 knowledge from 4.5-mile and 15.4-mile actions, and the ultimate distance in all probability would have been above 20 miles if not for this snafu.
Constant knowledge 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 fee, steps, cadence, and stride size.
Regardless of their completely different HR algorithms, accelerometer tech, and positions on my arms, they almost matched when calculating how far and infrequently I stepped — and the way exhausting I used to be pushing myself — throughout three hours. That is spectacular!
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By way of distance, I instantly seen that the GPS-only Pixel Watch 3 buzzed my wrist that I might completed my first mile properly 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 shortage of sign blockage on my route, a GPS-only watch is just ample 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 Pro’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 operating strides earlier than the Fenix 8 all the best way to the end.
For elevation knowledge, 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 past elevation accuracy test, so I am curious if the PACE Professional altimeter wants some tinkering. In any other case, I’ve discovered nearly any watch with an altimeter offers fairly constant ascent knowledge.
As for HR accuracy, I paired my COROS HR armband to the Tempo Professional for a baseline towards the opposite three watches, and the outcomes have been predictable: the Fenix 8 is glorious for optical HR accuracy, whereas the Pixel Watch 3 is regular however tends to fall slightly brief for anaerobic coronary heart charges. The Apple Watch Extremely 2 additionally appeared to do properly on common however fell a number of beats wanting my max HR.
The place health watch knowledge diverges
Contemplating how constant the outcomes have been in some areas, it’s kind of shocking how completely different the 4 watches’ outcomes have been in different areas:
Working energy: Among the best fitness watches calculate the vitality put into your run based mostly on components like pace, cadence, stride size, and vertical oscillation so you possibly can decide your stride’s effectivity and your total effort. You’d assume my operating energy knowledge would have been nearer throughout manufacturers. As an alternative, Garmin put my effort about 100W increased than the opposite two that tracked that knowledge.
I do know quite a lot of runners and specialists put inventory in using running power instead of pace to find out how properly or quick they’re operating, particularly on hilly or windy programs. However I’ve seen this variation in operating energy throughout manufacturers earlier than, and if they cannot agree on my wattage for a flat and non-windy course, it makes me leery of utilizing this metric as my benchmark whereas operating. It is one thing I wish to attempt to take a look at extra sooner or later.
Coaching load: TL is extra of a proprietary knowledge level, even when all of them use some type of the training impulse (TRIMP) method. So, I am not shocked that manufacturers differ in how they calculate it. Nevertheless it’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 would not put a quantity on exercises.)
For what it is price, I’ve seen up to now that Garmin is usually a bit conservative with its coaching load estimates (particularly for lengthy hikes) and isn’t very good at splitting low/high aerobic and anaerobic loads for one exercise. In the meantime, COROS offers 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 completely different manufacturers, the ultimate burned-calorie depend is completely different, irrespective 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 may nonetheless discover a distinction for shorter runs or walks, whichever health watch you purchase. And anybody attempting to drop some weight or decide their caloric want for the day will make very completely different life selections based mostly on this knowledge.
I might love to determine which model is most correct for caloric burn. However not like after I’m testing GPS routes towards satellite tv for pc maps or coronary heart fee towards 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 operating watch you possibly can belief is essential
This expertise taught me two issues. One, do not inform your boss, “Hey, I am operating 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, running watches are getting higher and extra dependable for uncooked knowledge than ever, matching one another throughout manufacturers in ways in which depend.
Garmin remains to be my most popular operating model as a result of I have been utilizing its coaching load, urged exercises, and restoration knowledge for years, and quite a lot of runners belief its accuracy. However exams like this make it plain that different manufacturers might be trusted too, at the 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.