Amazfit Cheetah 2 Pro Scientific Review
In a Nutshell
The Amazfit Cheetah 2 Pro delivers excellent GPS tracking with a 90/100 score and reliable heart rate monitoring during indoor cycling (0.98 correlation), weightlifting (0.95), and running, though outdoor cycling shows only acceptable performance (0.84 correlation). Sleep stage tracking scores 65/100 with typical accuracy (74% deep sleep, 60-61% light/REM), placing it in the second-to-third tier of current devices. The watch's strongest value proposition is its GPS performance combined with mapping features at $450, making it a strong alternative to much more expensive Garmin devices for runners and trail runners who pair it with an external heart rate chest strap.
These notes were generated by AI and may contain inaccuracies.
With a launch price of $450, the Amazfit Cheetah 2 Pro isn't the cheapest device from the brand but offers features typically found at higher price points from other manufacturers. The mapping functionalities match what would cost several hundred dollars more on Garmin devices. The review focuses on data analysis of the Cheetah 2 Pro as a running watch, comparing it to established brands like Garmin. GPS tracking performance was particularly impressive during testing.
The reviewer is Rob, a post-doctoral scientist specializing in biological data analysis. Testing methodology involves comparing device readings against reference standards: ECG chest straps for heart rate, Zmax EEG headband for sleep stages, and consistent route cycling/running for GPS accuracy assessment.
Indoor cycling (spinning) showed excellent performance with a correlation of 0.98 against ECG reference measurements. Points clustered closely around the ideal blue line, indicating reliable heart rate tracking. This represents the easiest exercise type for optical heart rate sensors.
Individual session analysis revealed minor issues in the first interval where the device detected slightly low heart rates, but subsequent sessions showed near-perfect agreement. The device occasionally struggled during the first interval but performed close to perfectly in the second and third sessions.
Among devices tested from 2025 onwards, the Cheetah 2 Pro's 0.98 correlation places it in the good performance category but not among absolute top performers. The device shares the same sensor as other Amazfit models including the T-Rex Pro, Active 3 Premium, and Active Max, resulting in similar performance characteristics.
Top-performing devices for heart rate tracking include Apple Watches (any model), Pixel Watches, and Huawei Watch Fit 5 Pro. The Amazfit Helio Strap worn on the biceps shows superior performance compared to wrist-worn devices, likely due to better positioning for reliable readings.
Running tests produced mixed results across two sessions. One run showed significant issues with a correlation of only 0.74, where the device detected excessively high heart rates, possibly mistaking cadence frequency for heart rate. The second run demonstrated near-perfect agreement with the ECG reference.
Due to injury limiting testing frequency, additional runs couldn't be conducted to determine if the poor performance was anomalous. Comparison with other Amazfit devices using the same sensor (T-Rex 3 Pro, T-Rex Ultra 2, Balance 2, Active Max, Active 3 Premium) suggests the outlier result might be a fluke, as these devices performed significantly better.
Outdoor cycling presented more challenges due to increased wrist movement and tension. The correlation of 0.84 indicates acceptable but not excellent performance. Individual session analysis showed varied results: some rides were nearly perfect while others missed heart rate peaks or showed more deviation.
Performance falls within the typical range for Amazfit devices with the same sensor (0.7-0.9 correlation range). The Helio Strap worn on the biceps again demonstrated superior performance for this exercise type.
Weightlifting sessions showed strong performance with a 0.95 correlation. Most exercise peaks were at least partially detected, which exceeds many competing devices. The device performed particularly well during high heart rate ranges when executing exercise sets.
In performance comparisons, the Cheetah 2 Pro ranks among top Amazfit devices for weightlifting, positioned close to the Helio Strap and Active 3 Premium, with the Balance 2 showing similar performance.
Using a new scoring system, the Cheetah 2 Pro received 85/100 points for heart rate tracking during cardio exercises (averaging indoor cycling, outdoor cycling, and running correlations). This places it in the "okay heart rate tracking" category.
Performance assessment: definitely good enough for indoor cycling, expected to be good enough for running pending confirmation of the anomalous result, and okay for outdoor biking where most issues appeared.
The Cheetah 2 Pro features Amazfit's newly updated sleep stage tracking algorithm. Testing compares against the Zmax EEG headband, which measures brain waves and serves as a silver standard for sleep research rather than the absolute gold standard.
Sleep detection showed 7 hours and 11 minutes total sleep time. Analysis focuses on sleep stage accuracy rather than awake time detection, as the Zmax identifies many brief arousals that don't represent actual wakefulness.
Deep sleep agreement reached 74% accuracy, considered good but not exceptional for current device capabilities. Light sleep showed 61% agreement and REM sleep showed 60% agreement. These figures represent typical performance levels rather than standout results.
Performance comparison places the Cheetah 2 Pro in the second to third tier of devices. It performs similarly to the Active 3 Premium (which shares the updated algorithm) and shows improvement over older Amazfit devices, particularly in REM sleep tracking.
Current top-performing sleep tracking brands include Google (Pixel watches), Fitbit devices, Apple Watches, Oura Ring, Whoop Strap, and Eight Sleep Pod. Galaxy Watches represent the second tier, with Amazfit devices performing slightly better than Garmin and Polar devices but not matching Galaxy Watch capabilities.
The new algorithm shows clear improvement over previous Amazfit versions, especially for REM sleep detection. However, significant room for improvement remains to reach top-tier performance levels.
The Cheetah 2 Pro received a sleep stage tracking score of 65 based on average sensitivity across sleep stages. This falls into the "okay sleep stage tracking" category - not good or great, but substantially improved compared to most devices from one to two years ago.
GPS accuracy testing involves cycling and running identical routes multiple times, with overlapping signals indicating good performance. Signal acquisition speed and consistency between repeated traversals of the same route determine overall GPS quality assessment.
Signal acquisition occurred almost instantly at both testing locations. Six cycling signals overlapped almost perfectly, with minimal deviation even in challenging areas. Roundabout navigation showed consistent tracking, and performance remained solid near radio towers where many devices typically struggle.
Additional testing with four commutes to work confirmed good consistency with only minor deviations. Corner navigation and signal maintenance throughout routes demonstrated reliable performance.
Running tests around a circular route with a large wall on one side (creating signal interference) showed good signal convergence. Minor deviation occurred near the wall's end where most devices struggle, but overall performance remained solid.
A second running test produced nearly identical results with very close signal grouping, particularly on the left side of the route with no wall interference.
GPS performance represents a major strength of the Cheetah 2 Pro, especially when paired with external chest strap heart rate monitoring. This combination provides excellent heart rate accuracy plus reliable GPS tracking and mapping capabilities at a significantly lower price point than equivalent Garmin devices.
GPS tracking receives a score of 90, placing it in the category of great. This testing is limited to personal experience but provides valuable data points for evaluation.
GPS tracking stands as the standout feature with a score of 90, falling into the great category. Heart rate tracking achieves a score of 85, classified as okay. Sleep tracking receives a score of 65, also rated as okay.
The heart rate tracking score may have been impacted by a potential fluke run that decreased the overall rating. If this proves to be an anomaly, heart rate tracking could potentially move up to the great category. However, some struggles were observed during outdoor cycling activities.
External Heart Rate Recommendations
For the most accurate heart rate tracking, connecting an external chest strap is recommended. Alternatively, combining the device with the Amaze Helio strap worn on the biceps provides another option.
For individuals who engage in frequent running and trail running activities, the device is recommended specifically due to its GPS tracking performance.
The approach focuses on presenting the data directly, allowing viewers to determine whether the performance meets their personal requirements. Cross-referencing with other reviewers is also advised.
For those considering the Amaze Vegeta 2 Pro, the Whoop Strap is recommended as the favorite overall sports and health tracker, the Aura Ring as the favorite sleep tracker, and the Eight Sleep Pod as the favorite sleep improvement device. Affiliate links are available for obtaining the best possible discounts.
Using general Amazon affiliate links supports the channel without additional cost to the purchaser, regardless of purchase type including everyday items.
Viewers interested in the Amaze Fit Cheetah 2 Pro may also find value in content covering the Amaze Fit Helio Strap, a cost-effective non-screen wearable that performs well for heart rate tracking, and the ACLE pod.
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