A method for assessing cardiac wellness in a human utilizes high definition EKG signals to detect, analyze and compare waveform feature signatures at rest and during recovery from exertion. The parameters measured and displayed include beat-to-beat heart rate, heart rate variance and rate of recovery, which are indicators of the underlying physiological state. Combining these capabilities in a wearable device enables direct feedback to the user regarding overall fitness and physiologic response to therapeutic or behavioral interventions.