A Quantified Scientist test found Garmin’s screenless CIRQA tracked running heart rate at 0.98 correlation on the biceps versus 0.89 on the wrist, with the gap widening during high-intensity intervals.
Placement drove results across workouts: indoor cycling reached 1.0 on the biceps and 0.99 on the wrist, while strength training improved to 0.91 from 0.73 when moved off the wrist.
Sleep tracking was more mixed, with biceps placement lifting deep-sleep agreement to 91% from 81% and REM to 58% from 45%, but still trailing Fitbit and Whoop in REM accuracy.
Nighttime HRV and heart-rate monitoring remained consistently strong on both placements, reinforcing CIRQA’s appeal for recovery-focused users despite its bulkier design and occasional missed auto-detection on the biceps.
The review suggests CIRQA is strongest for athletes who prioritize exercise precision and recovery data, though roughly $60 official biceps bands and weaker sleep-stage performance could limit broader appeal.