To characterize Cardio Age derived from wearable devices and its association with independent lifestyle factors.
Approach:
Study Design: Retrospective observational cohort study of 442 Ultrahuman Ring users over 12 months.
Data Analysis: Used Spearman rank correlations, extreme-group comparisons, and longitudinal trajectories.
Key Findings:
Mean Cardio Age gap was -1.84 ± 2.97 years; 82.6% of participants had younger estimated cardiovascular ages.
Significant associations with independent lifestyle metrics: sleep efficiency (r = -0.194, p < 0.001), REM sleep (r = -0.203, p < 0.001), sleep duration (r = -0.200, p < 0.001), and daily steps (r = -0.145, p = 0.003).
Underweight participants had a mean CA gap of -3.73 years compared to -0.52 for obese participants.
Users with the youngest cardiovascular ages had longer sleep duration and higher sleep efficiency.
Interpretation:
Cardio Age reflects physiological and behavioral variations beyond algorithmic inputs, indicating its potential as a continuous cardiovascular fitness indicator.
Limitations:
Study is observational and may not establish causation.
Potential algorithmic circularity due to Cardio Age being derived from VO2 max.
Conclusion:
Cardio Age may serve as a practical tool for monitoring cardiovascular fitness, capturing real physiological changes over time.
