TLDR;
This video provides a scientific and systematic review of the Amazfit Helio Strap, a Whoop alternative, by comparing its performance in heart rate and sleep stage tracking against industry standards. The reviewer tests the device worn on both the biceps and wrist during various activities, evaluating its accuracy and usability. The video concludes with a discussion on the subjective app experience and recommendations based on different user needs, highlighting the strengths and weaknesses of the Amazfit Helio Strap compared to competitors like Whoop, Apple Watch, and Garmin.
- The Amazfit Helio Strap performs exceptionally well in heart rate tracking, especially when worn on the biceps, rivaling top-tier devices like Apple Watch and Pixel Watch.
- Sleep stage tracking is a weak point, with accuracy lagging behind competitors like Eight Sleep Pod, Apple Watch, and Whoop.
- The app experience is decent but not as refined as Whoop, though the absence of a subscription fee makes the Amazfit Helio Strap an attractive option for budget-conscious users.
Introduction [0:00]
The Amazfit Helio Strap is presented as a Whoop alternative that doesn't require a subscription. The reviewer, Rob, a data scientist, expresses initial skepticism but notes that the device has surprisingly performed well in some tests. The video aims to scientifically test the device's measurements when worn on the biceps and wrist, comparing it to competitors and evaluating its app for data interpretability.
Heart Rate Tracking: Cycling Indoors [3:07]
The Amazfit Helio Strap's heart rate tracking performance during indoor cycling is examined, comparing the device worn on the wrist against a Polar H10 ECG chest strap (reference device). The data reveals a strong correlation (0.99) between the Helio Strap on the wrist and the chest strap, indicating high accuracy. When worn on the biceps, the correlation improves to 1.00, suggesting even better accuracy due to the less bony surface. Individual cycling sessions confirm the device's ability to closely match the reference device, with only minor deviations during rapid heart rate changes.
Heart Rate Tracking: Running Outside [8:32]
The assessment shifts to running outdoors, where the Amazfit Helio Strap on the wrist shows a good correlation of 0.98 with the reference device. The bicep placement achieves a perfect correlation of 1.00, highlighting a significant advantage over wrist placement. Individual running sessions reveal that the bicep-worn device calibrates faster and maintains accuracy throughout interval runs, reinforcing the potential benefit of waiting for Amazfit's official bicep band.
Heart Rate Tracking: Cycling Outside [13:08]
During outdoor cycling, the performance of the Amazfit Helio Strap on the wrist decreases slightly, with a correlation of 0.9. The bicep-worn device maintains a high correlation of 0.99, demonstrating its superiority in this activity. Individual bike rides show that the wrist-worn device occasionally loses heart rate or detects too low a heart rate, while the bicep-worn device provides almost perfect agreement with the reference.
Heart Rate Tracking: Weightlifting [16:37]
Weightlifting proves to be the most challenging activity for heart rate tracking. The Amazfit Helio Strap on the wrist shows a lower correlation of 0.89, with frequent underestimations of heart rate during sets. The bicep-worn device performs significantly better, with a correlation of 0.98, although it still occasionally misses peaks in heart rate. Despite some missed peaks, the bicep-worn device is deemed good enough for tracking heart rate during weightlifting.
Sleep Stage Tracking [19:59]
The video evaluates the sleep stage tracking capabilities of the Amazfit Helio Strap by comparing its data to the Zmax EEG device, a dedicated sleep stage tracker. The results indicate that the Amazfit Helio Strap's sleep stage tracking is not very accurate. Deep sleep agreement is around 50%, light sleep agreement is decent at 75%, and REM sleep agreement is poor at 36%. The device often confuses deep sleep with light sleep and struggles to accurately identify REM sleep.
Subjective Experience and App [28:56]
The reviewer discusses the subjective experience of using the Amazfit Helio Strap, noting that the app seems to emulate the Whoop Strap app. While the app provides an overview of metrics like resting heart rate, heart rate variability, and sleep duration, the reviewer finds the Whoop Strap app slightly better for its feel and data overview. The reviewer appreciates Whoop's health span metrics and gamified experience but acknowledges that Amazfit offers better heart rate tracking and lacks a subscription fee.