Garmin Cirqa Heart Rate Accuracy: Strong for Runs, Weak for Weights
The screenless tracker excels in steady-state cardio but struggles with strength training due to hardware limitations.
The Garmin Cirqa's reliance on its internal optical sensor is a critical point of failure or success for users, as the device cannot be paired with external heart rate monitors. Recent testing by Tom's Guide reveals that while the tracker is highly accurate for running, it falters during strength training.
In a series of tests conducted by journalist Nick from Tom's Guide, the Cirqa was pitted against a Garmin HRM 600 chest strap. The results showed the device performed exceptionally well during easy runs and remained impressive during interval training. However, the tracker showed mixed results and lower accuracy during strength workouts, where the optical sensor struggled to keep pace with the chest strap's precision. Nick noted that during a run, the Cirqa matched the chest strap "beat-for-beat," passing the test with "flying colors."
The Hardware Trade-off
The performance gap is partly explained by the hardware inside the device. The Garmin Cirqa utilizes the Elevate Gen 4 heart rate sensor rather than the more advanced Gen 5 found in newer Garmin wearables. According to Garmin, the Gen 5 sensor was simply too large to fit within the Cirqa's compact, screen-free chassis. This design choice forces the device to rely on older optical technology to derive its health metrics, including sleep tracking and training readiness.
Why Sensor Accuracy Matters
For most Garmin users, a dip in wrist-based accuracy is solved by pairing a chest strap or arm band to the watch. The Cirqa, however, lacks this capability, meaning users are entirely dependent on the onboard optical sensor for all high-intensity training data. While the Gen 4 sensor is reliable for steady-state cardio, the lack of external pairing makes the device less effective for athletes who prioritize strength training or high-variability workouts.
What to Watch
As Garmin continues to iterate on its screenless health trackers to compete with the likes of Whoop and Fitbit Air, the integration of newer sensor generations will be the primary benchmark for success. For now, the Cirqa remains a strong tool for runners and general wellness tracking, but those requiring medical-grade precision during weightlifting may find the Gen 4 hardware limiting. The inability to offload data processing to a chest strap means the device's utility is capped by the physical constraints of its wrist-based sensor.