Continuous Hand-to-Foot and Segmental Bioimpedance Spectroscopy Measurements within a Period of Five Days

Abstract

The possibility of monitoring the body hydration during the day on elderly people has been proposed by several authors. The aim of this investigation was to examine the variation of the measured body fluids during the day and during five days with hand-to-foot (HF) and knee-to-knee (KK) BIS measurements. Measurements on seven elderly and four young test subjects during the day show a repetitive pat-tern from day to day (circadian rhythm), indicating a possible influence due to changes of body position and amount of movement. The measured change in body fluids during a day is higher than the measured change in weight and than the necessary loss to define a mild dehydration. Age seems to have less influence than movement in the amplitude of oscillation observed during five days.