Abstract: A method for determining the hydration status of a person prompts the person to breathe while in a first postural position during which the method measures a first heart rate variability (HRV) value. The person is prompted to change to a second postural position, and the method measures a second HRV value. A difference between the first HRV value and the second HRV value is a daily score. The daily score is subtracted from a baseline to obtain a hydration score. In certain embodiments, the person is requested to respond to a plurality of subjective questions. The method processes the subjective responses and the daily score to determine whether the person is adequately hydrated. In certain embodiments of the method, the person is requested to identify the color of the person's urine. The identified color is processed with the daily score and the subjective responses to determine hydration.

Abstract: A method for determining the hydration status of a person prompts the person to breathe while in a first postural position during which the method measures a first heart rate variability (HRV) value. The person is prompted to change to a second postural position, and the method measures a second HRV value. A difference between the first HRV value and the second HRV value is a daily score. The daily score is subtracted from a baseline to obtain a hydration score. In certain embodiments, the person is requested to respond to a plurality of subjective questions. The method processes the subjective responses and the daily score to determine whether the person is adequately hydrated. In certain embodiments of the method, the person is requested to identify the color of the person's urine. The identified color is processed with the daily score and the subjective responses to determine hydration.