Relationship of the Natural Body Damping and Body Frequency to the Ballistocardiogram

Abstract
By means of a direct body ballistocardiograph the relationship of body frequency and damping to the ballistocardiogram in normal subjects was investigated. The influence of age and body measurements were studied and the findings subjected to statistical analysis. The degree of body damping was related to age but not to anthropometric measurements. Overweight and underweight influenced body frequency but not body damping. Respiratory changes had no influence on either body frequency or damping. It was suggested that to record a true ballistocardiogram of the cardiovascular forces more consideration must be given to body damping.