Polar LOOP Review – It’s NOT A Whoop Competitor

Polar LOOP is marketed as a Whoop competitor, but it isn’t. At least not yet.

There are some specific issues that I’ll talk you through and get straight to the point in these key areas:

1. The app
2. The band format – aesthetics and wearability
3. Reliability of the band and its data.

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Polar LOOP – The positives

Polar LOOP has two key positives. First, unlike Whoop, it’s relatively inexpensive and has no subscription. It’s free to use for life after you’ve bought it. Second, it slips very sweetly into the Polar ecosystem—great for existing Polar owners.

Those two positives indicate precisely who Polar LOOP is best suited for

1. Existing Polar Owner – Sometimes you don’t want to wear the watch – when asleep, for example. Polar LOOP fills in the gaps and analyses sleep
2. On a budget – You can’t justify the cost of Whoop, but you want a 24×7 activity and sports tracker

Other arguments around supporting an EU company would be essential for a minority but peripheral for most.

Polar LOOP – The Negatives

I’m slightly disappointed for those hoping for a more direct competitor to Whoop. Perhaps you should hold fire on hitting the button on the Whoop subscription to see what comes out.

Negative 1: The Polar LOOP Band and the overall form factor

The product’s format is nice enough, and it’s well-made. However, there are three design drawbacks.

LOOP needs an arm sleeve option. I’ve worn mine on the biceps with other sleeves and bands, which boosts wearability and accuracy. But Polar needs to do that with the shipped product; failing that, there needs to be an accessory.

Then there is the lifestyle aspect of the product. Whoop sells spare bands and apparel that its pod can be slipped into, which was developed as the company expanded. We can’t expect Polar to sell branded apparel from day one, but we could expect them to ship a product with a band that’s more easily swapped several times a day. I can change a Whoop band in 10 seconds; changing the Polar LOOP band takes 30-60 seconds. This might seem trivial, but the current design adds the faff factor if you want to swap a sweat-drenched one for one you used in your lunch break for another to wear at work in the afternoon.

Negative 2: The Polar FLOW App

The Polar FLOW app is nowhere near as capable as the Whoop app. This is a big hurdle to overcome, as the app is key to the experience for this type of display-free product. To counter that, Polar does have the core knowledge, experience, and science behind the scenes, but it’s not manifested in the app in the comprehensive way it is with Whoop.

The Polar Flow smartphone app is very much a reporting and charting tool. Whoop is significantly more advanced, adding extra layers of insight and knowledge with its Coach and well-designed dashboard.

Polar realises this and has shared conceptual plans for a reimagined Polar FLOW next year. But that’s not now.

As things stand today, several forum reports of pairing and syncing issues are spoiling some people’s experience after launch. Using iOS has been broadly OK for me outside of those specific issues.

Even though the app will soon change, I’ve included a few screenshots to give those of you thinking of getting one an idea of what to expect now. For example, Polar FLOW gives you a doughnut view of the day with tappable highlights, covering a workout, your maximum HR, your HRrest, and your HR when asleep.

The clear and concise workout view shows workout highlights and heart rate zone details; it presents good glanceable information.

 

Turning to the sleep data, Polar captures all the key sleep metrics. However, its data presentations were novel when launched, but now look dated and overwhelming for the casual Loop owner just coming for a recap.

Polar LOOP Accuracy

Several third-party reports from early LOOP adopters mention incorrect calories, steps, and workouts with wrong start and finish points. I’ll leave those by mentioning them and go straight to my accuracy tests and results.

As an overview of the accuracy piece, I’ll say two things. Firstly, it’s more accurate when worn on the biceps (not a big surprise there), but oddly, it’s less accurate than its OH1/Verity Sense predecessor, which I have used for years as a reference-grade device for optical HR.

That said, the overall level of accuracy on the biceps feels sufficiently accurate for the job when taken in the round, at least in my tests. Let’s go through some of the details.

Test Methodology

I overlay heart rate tracks from multiple recording devices in each test. I’ve tested across various sports, including a triathlon race, a hyrox simulation, a gym workout, yoga, running, and cycling. One note I will make is that all these tests are made by recording to a workout initiated by the FLOW app, then the phone left behind, from what Polar says, below, this should mean that my data is post-processed by the app with corrections applied by Polar.

When recording training directly with Polar Loop, the device applies a correction algorithm to heart rate data every 90 seconds, ensuring the highest possible accuracy. [Source: Polar]

All the tests are proper workouts that form part of my regular training, not just me making random shopping trips or work and back.

The results clearly show obvious errors visually, and I’ve annotated the charts to highlight the more interesting areas.

Polar Loop Accuracy Test results for Running

This was a relatively steady hour-long run, during which I bumped into an old friend halfway around for a chat. Polar LOOP performed perfectly here and aligned with Apple Watch Ultra 3 and the reference HRM 600. In the second half of the run, you can see that the Garmin Elevate 5 OHR sensor struggled to respond to restarting the workout.

Polar LOOP  easily gets a 9/10 here.

 

Polar Loop Accuracy Test results in the Gym

I brought Amazfit Helio into the mix for a gym session where I mainly focused on upper body work, which will most likely negatively impact arm-worn sensors like LOOP. Polar LOOP struggled a little bit here at times, and I’ve highlighted those on the chart – you can see that it didn’t always register increased efforts, and, as a result, the overall workout average was 104.50bpm, which was 1 or 2 beats lower than all the other devices on test. You can see that Amaxfit Helio over-reports to the reference device by 1bpm, and Whoop is spot on with the HRM 600.

These differences from the reference track by all the devices have no significance. Even if they did, measuring HR during weights is pointless unless you have a method to determine the muscular strain (Whoop does, Helio doesn’t).

Polar LOOP  gets a 7/10 here.

 

Polar Loop Accuracy Test results in Hyrox

I’ve recently gotten into the habit of doing two Hyrox simulations in the gym each month. These intersperse running with 8 specific activities. The activities stress the full body, but with special weight on the quads, and the carrying, pulling and throwing workouts involve significant wrist and arm movements. The test results very oddly show the reference device to likely be wrong – I can’t explain that one, and they also showed Watch Ultra 3 with an HR dropout period. Putting those two devices aside, Whoop, Polar LOOP and Amazfit Helio report virtually identical results. This is surprisingly good and probably a 10/10 for Polar LOOP!

Polar Loop Accuracy Test results in Open water Swim (Wetsuit)

LOOP performs surprisingly poorly during an open water swim while wearing a wetsuit. Although not as bad as the Apple Watch Ultra 2, which experienced numerous dropouts, LOOP significantly underreported at the start of the workout and slightly underreported the reference device for the remainder. Garmin and Whoop were similar; both got a good start on the reference device but fell behind it like LOOP as the workout progressed. Interestingly, the Garmin and Polar recorded a similar average of 10 beats below the reference device, a significant amount.

Oh dear, Polar scores 5/10 here.

 

 

Polar Loop Accuracy Test results for Yoga

I’m reasonably OK at yoga, and oddly enough, my heart rate usually goes higher than when doing weights. The yoga movements are extreme and will affect blood flow, but they don’t strain the arm muscles in quite the same way as weights.

Over an hour, I compared the warm-up, cool-down, and intense middle period, and Polar LOOP only had a small number of sections where it slightly under-reported against the Apple Watch Ultra 3, Garmin HRM 600 and Whoop. The underreporting was in the 70-100bpm range, where any discrepancy will make zero difference to a traditional ATL/CTL/TRIMP score.

Polar gets another 9/10 on the accuracy scores.

 

Polar Loop Accuracy Test results for Triathlon

In a non-wetsuit triathlon race, I wore a tightly fitting tri-suit in cool weather. I forgot to set the HRM600 recording by itself, so I only have its data that showed on a bike computer. Whoop was not great this time; despite being in roughly the right range, it either over- or under-reported the reference device. Perhaps the tri-suit was pulling on the arm sleeve it covered? The LOOP was worn with an old Coros band I wore around the biceps, and it recorded a good track.. Garmin was OK until it got to the run where it inexplicably significantly overreported and was plain wrong.

Good performance from Polar LOOP, 8/10.

Polar Loop Accuracy Test results for Outdoor running

The following chart shows the results from a 90-minute trail and road run. It was a steady-state effort, but included some hard uphill sprints off-road. The Apple Watch again experienced some dropouts, and there was near-perfect agreement among the other devices and with the reference track.

Great job from Polar here, scoring 9.5/10

 

Note: Test used software version number: 3.0.31.this was the launch version, superseded on 29 September.

Whoop Competition – the state of play

If you are looking for a direct Whoop competitor, there isn’t one. Several companies are clearly heading towards adapting their ecosystem to take Whoop head-on; it’s just a case of who gets there first and when.

Garmin – Garmin’s Index Sleep Monitor was a missed opportunity to develop a strong 24/7 product based on its excellent Elevate 5 sensor package. You can wear Garmin’s band all day if you want, but the experience is tailored towards sleep – hence its name. Its recent Health Status and Lifestyle Logging features will likely be steps towards a more cohesive Whoop competitor, perhaps as soon as next Spring.

Amazfit Helio is probably the most competitive and cheapest Whoop competitor. It seems to be a one-trick pony precisely aimed at undercutting the price of Whoop and copying the easier features. It hasn’t yet reached the polish and depth of the Whoop app’s features, but it’s well on its way.

There are many other heart rate bands, but few, if any, have a long enough battery life or the app to compete as Whoop does as a sports and health lifestyle coach.

Wrap Up – Polar Loop Review

Polar LOOP is an excellent add-on for existing Polar watch customers. It’s a decent sleep and activity tracker—or at least it will be once Polar pushes out a few firmware tweaks—nothing too major.

As a Lifestyle competitor to Whoop, I’m unconvinced about the strap mechanisms and lack of a biceps sleeve. But Polar has probably done enough on the physical design for a credible 24/7 offering. What I’ve seen of the next-gen app and its screen mockups is good, but you won’t buy Polar LOOP based on promises, and neither will I recommend it.

Core HR accuracy levels on the biceps are very good but not excellent. I’m surprised Polar has not refined its algorithms for widespread use over the last year or so with the sensor package on the B2B version of LOOP.

Over the next 6 or so months, Polar will struggle to match the customer perception of Amazfit Helio – a better-looking app and cheaper product. Amazfit has the potential to be nimble and add and refine features to stay ahead. But Amazfit historically seems to lose interest in software improvements, so don’t hold your breath. Garmin appears to present a credible Whoop competitor. No doubt they will eventually produce something plausible, but like its predecessors, I suspect whatever comes will be a great piece of hardware, but software well below the high bar set by Whoop.

In summary, buy Polar LOOP to complement your Polar Watch. Wait for the app update if that doesn’t describe you. If you want to take a punt now, it’s OK; Polar is in this for the long term.

No one is threatening Whoop’s dominance, just yet.

Check Polar LOOP pricing at the authorised retailers linked here: