Polar Loop vs Amazfit Helio Strap: Two Whoop alternatives compared

Polar jumped into the subscription-free band space in September with the Loop, while Zepp Health had already put out its Helio Strap back in June. Both take the same stripped-back approach, skipping a screen and going all-in on recovery and simple tracking. On the surface they look a lot alike, but once you start using them the differences quickly show. And so do the weak spots.

Both products are positioned as direct alternatives to Whoop. That is a deliberate play, since Whoop has owned this niche of screenless, always-on recovery bands for years with little competition. The market matters because it caters to users who want deeper insight into training load and recovery without the constant noise of notifications or smartwatch distractions.

Neither is quite there, yet. But if Polar or Zepp Health can refine their platforms enough, they could offer a one-off purchase route to Whoop-like insights, which is something many users have been waiting for.

You can check out the Amazfit Helio on the Zepp Health website or Amazon. Polar Loop is available on the company’s website.

Design and hardware

Starting off with design, and on the outside both devices are simple rectangles with no buttons and no screens. Polar’s Loop weighs in at 29 grams, built from stainless steel and polymers, while Zepp Health’s Helio Strap is lighter at 20 grams and comes with a robust nylon strap and velcro buckle. Neither feels particularly flashy, but both are comfortable for 24/7 wear and can be shifted to the upper arm if you want more accurate heart rate readings. Not too much to write about here.

As far as battery life, that’s solid in both cases. You get around eight days for the Loop and ten days for the Helio Strap. Helio does have the larger cell inside, rated at 232 mAh compared to Polar’s 170 mAh.

Water protection is another split, with Polar promising 30 meters and Amazfit going a bit higher with a 5 ATM rating. For most people, either will suffice on this count.

Health and fitness tracking

This is where Polar and Amazfit take different approaches.

Polar’s Loop leans heavily into its existing Flow ecosystem. You get continuous heart rate, HRV and ANS data, along with recovery tools such as Nightly Recharge, SleepWise and Sleep Plus Stages. For training, there is Training Load Pro, fitness testing and energy expenditure tracking.

But unlike with the Amazfit, you don’t get blood oxygen and skin temperature. Technically, the Polar Loop has a skin temperature sensor built in, but you won’t see any of that data in the Flow app. The feature is marked as “Skin Temp Gen 1” and set up for developer access only through the Polar SDK. That means the hardware is there, but for regular users it’s hidden away and not part of the day-to-day tracking experience.

The other weakness with Polar Loop is workout detection. Automatic recognition is unreliable, which means you often need to log sessions manually or start them from the app. Still, the cardio load and recovery tools remain more advanced than what the Amazfit currently provides.

Essential reading: Top fitness trackers and health gadgets

Amazfit’s Helio Strap goes broader. It tracks heart rate, variability, sleep stages, naps, stress, skin temperature, blood oxygen respiration rate and even sleep apnea estimation. On top of that it has PAI, Exertion and BioCharge, which is similar in concept to Garmin’s Body Battery. Training Status and Training Load are included, but the emphasis feels more on daily wellness than structured training. The Zepp Health app was revamped recently, with sections designed to look more like Whoop, but the insights remain shallower than Polar’s Flow platform.

Worth noting is that the Polar Loop and Amazfit Helio Strap don’t have built-in GPS. But fire up a run or ride through the app, and you’ll find distance, pace and route info via your phone’s GPS signal for an activity. If you just head out wearing the band without opening the app, you won’t get any location data.

Another practical detail worth noting is that the Helio Strap can broadcast heart rate to another device, such as a watch or bike computer, while Polar’s Loop cannot. That gives the Amazfit a useful edge if you want your data on more than one platform. On the flip side, Polar’s optical sensors still tend to be more accurate for workouts.

Final thoughts

So is either of these a true Whoop competitor? Not yet.

While the hardware is good, the biggest gap for both devices is still software. Whoop has polished its app to a high standard, creating a stickiness that neither Polar nor Zepp Health have matched yet. Polar’s Flow app is reliable but dated, though the company has promised a major refresh is coming. If delivered well, that could make Loop a much stronger competitor. No set timeline for that, though. Zepp Health already did its refresh, but while the Zepp Health app looks the part, its coaching and correlation features don’t go as deep.

What works in their favour is cost. Polar Loop retails at $199 while Amazfit Helio Strap comes in at $99. Both are one-off purchases with no subscription fees. That is half the cost of Whoop in its first year alone. You do give up some of the polish and feedback depth, but you also avoid ongoing charges.

At this stage, Polar Loop feels more appealing for serious training and recovery use, especially if you are willing to wait for the app update. It has deeper insights into cardio load and readiness, even if workout detection can be frustrating. Amazfit Helio Strap wins on value and daily lifestyle tracking. It is lighter, cheaper and more versatile in how you wear it, but its software leans towards general lifestyle and wellness.

Neither is a complete Whoop replacement yet. But both show that alternatives exist, and with continued software updates they may grow into genuine rivals. For now, the choice is between Polar’s deeper training focus and Zepp Health’s lighter, more affordable daily strap.

Polar Loop – buy if:

• You want deeper recovery tools like Nightly Recharge, SleepWise, HRV and ANS tracking.
• You’re already in the Polar ecosystem and use Polar Flow.
• Accurate optical heart rate tracking matters more than extra lifestyle metrics.
• You don’t mind the lack of a screen or workout auto-detection quirks.

Amazfit Helio Strap – buy if:

• You prefer a lighter, cheaper device with strong battery life.
• You want broader wellness tracking, including blood oxygen and skin temperature.
• You like BioCharge and Exertion metrics for daily energy awareness.
• You prefer longer battery life, up to 10 days on a charge

You can check out the Amazfit Helio on the Zepp Health website or Amazon. Polar Loop is available on the company’s website.

Polar Loop vs Amazfit Helio Strap: Tech specs comparison

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