Amazfit Helio Strap Review: Whoop Alternative?

TL;DR

The Amazfit Helio Strap delivered highly accurate heart rate tracking during indoor cycling and outdoor running, especially when worn on the biceps. Wrist performance was also strong, but the biceps placement produced correlations as high as 1.00 against a Polar H10 chest strap. Its subscription-free model is appealing, although the app and data interpretation still need improvement.

Transcript

This Whoop alternative, the Amazefitit Helio Strap, is doing surprisingly well in my testing. When I originally received it, I was very skeptical if this device that doesn't require a subscription could do possibly as well or even better than the Whoop Strap. However, in some ways, it's outperforming the Whoop Strap, but in other ways, it's not qui... Read More

Key Insights

• The Amazfit Helio Strap can track exercise heart rate with nearly perfect agreement against a Polar H10 chest strap. Its strongest results occurred during indoor cycling and outdoor running, where most recorded points stayed on or very close to the reference line.
• Biceps placement is more accurate than wrist placement in the reviewer’s testing. The biceps unit reached rounded correlations of 1.00 during both indoor cycling and outdoor running, while the wrist unit produced correlations of 0.99 and 0.98, respectively.
• The biceps may provide a better optical measurement location because it has a fleshier, less bony surface than the wrist. The reviewer suggests this physical difference may make heart rate fluctuations easier for the Helio Strap to detect accurately.
• Wrist performance is still highly accurate for common endurance exercises. During spinning and running sessions, the wrist-worn Helio Strap generally followed the Polar H10 reference closely, with only minor deviations during sudden drops, high heart rates, or initial calibration.
• Sudden heart rate changes remain a difficult test for the Helio Strap. During extreme intervals, the device occasionally failed to capture an abrupt drop fully, although these errors were limited and did not substantially undermine its otherwise strong overall agreement.
• The Helio Strap ranks among the best devices previously tested by the reviewer for indoor cycling. Its results were close to those of the Amazfit Bip 6, several Huawei devices, the Pixel Watch 3, and some Apple Watches.
• The Helio Strap does not require a subscription, making it a potential alternative to the Whoop Strap. However, accurate measurements alone are not sufficient, because the collected data must also be presented in a form that users can interpret and apply.
• The accompanying app is a weaker part of the current experience according to the reviewer. Although the hardware produced excellent heart rate measurements, the presentation and interpretation of its data still need improvement before the overall system can compete fully with Whoop.

Questions & Answers

Q: How accurate is the Amazfit Helio Strap for heart rate tracking?

The Amazfit Helio Strap was highly accurate during the exercises shown. Against a Polar H10 chest strap, the wrist unit reached correlations of 0.99 for indoor cycling and 0.98 for outdoor running. The biceps unit reached rounded correlations of 1.00 for both activities, with most measurements lying on or very close to the reference line.

Q: Is the Amazfit Helio Strap more accurate on the wrist or biceps?

The biceps position was more accurate in the reviewer’s tests, although wrist performance was already strong. During indoor cycling, correlation improved from 0.99 on the wrist to 1.00 on the biceps. During outdoor running, it improved from 0.98 to 1.00. The biceps unit also avoided some calibration and lower-range deviations seen at the wrist.

Q: Why does biceps placement improve Helio Strap accuracy?

The reviewer suggests that the biceps is easier for optical heart rate measurement because it provides a fleshier and less bony surface. The wrist contains more bone, which may make pulse-related fluctuations harder to detect. This explanation is consistent with the observed results, where the biceps unit produced closer agreement with the Polar H10 reference.

Q: How well does the Amazfit Helio Strap track indoor cycling?

Indoor cycling was one of the Helio Strap’s strongest activities. The wrist unit achieved a correlation of 0.99 against the Polar H10, while the biceps unit reached a rounded 1.00. Both followed interval spinning sessions closely, although they occasionally missed part of a sudden heart rate drop or showed small deviations near peak heart rates.

Q: How well does the Amazfit Helio Strap track outdoor running?

Outdoor running accuracy was excellent in the sessions presented. The wrist-worn unit achieved a correlation of 0.98 and generally followed the reference closely, with brief errors during initial calibration and at lower heart rates. The biceps unit reached 1.00 and showed nearly perfect agreement, apart from isolated differences of roughly 3 or 4 BPM.

Q: Does the Amazfit Helio Strap struggle with interval workouts?

The Helio Strap generally handled interval workouts well, but abrupt changes could expose small weaknesses. During extreme tests involving sudden heart rate drops, it sometimes failed to follow the reference all the way back toward resting heart rate. These misses were limited, and the device otherwise tracked interval cycling and running curves with nearly perfect agreement.

Q: Does the Amazfit Helio Strap require a subscription?

The Helio Strap is presented as a subscription-free alternative to the Whoop Strap. That removes one potential ongoing requirement, while the tested hardware still produced highly competitive heart rate measurements. However, the reviewer emphasizes that useful fitness tracking also depends on understandable data, and the Helio app’s interpretation and presentation still need improvement.

Q: Should I wait for the official Amazfit biceps band?

Waiting for the official biceps band may be worthwhile if maximum heart rate accuracy is the priority. The reviewer used a sleeve originally designed for the Whoop Strap 4.0 because no official Amazfit biceps band was available. Even with the current firmware and unofficial sleeve, biceps placement outperformed wrist placement in the presented cycling and running tests.

Summary & Key Takeaways

• The Amazfit Helio Strap was tested for several weeks in wrist and biceps positions, with heart rate measurements compared against a Polar H10 chest strap. The reviewer focused primarily on exercise heart rate and sleep-stage tracking, while also examining whether the accompanying app makes the collected health data understandable and useful.

• During indoor cycling, both placements produced nearly perfect agreement with the reference chest strap. The wrist unit reached a correlation of 0.99, while the biceps unit reached a rounded correlation of 1.00. Sudden heart rate drops occasionally caused small errors, but overall performance ranked among the strongest devices previously tested.

• Outdoor running results reinforced the advantage of biceps placement. The wrist unit achieved a correlation of 0.98 and showed brief calibration and low-range deviations, while the biceps unit reached 1.00 with only minor errors. The device appears to be a strong subscription-free alternative, although its app still requires refinement for interpretation.