Aging in vertical body sway

Abstract

Standing position is basic for human. We studied body vertical sway with aging. METHOD: Subjects were 1784 healthy volunteers, aged from 3 to 94 years (yrs). Sum of the 3 signals from the gravicorders (G5500, ANIMA Corp. Japan) were analyzed for 1 min with eyes open (EO) and feet closed (FC), for 1 min with eyes closed (EC) and FC, for 1 min with EO and feet open (FO), for 1 min with EC and FO. The signals were sampled at 20 Hz and analyzed with the fast Fourier transform. RESULTS: With FC, the oscillation with EO was more stable than that with EC for all age groups. The oscillation around 7 Hz increased with the age with FC. The oscillation around 3 Hz was noted for the age group between 3 and 10 yrs, with EC and FC. With FO, the oscillation around 3 Hz was noted for the age group between 3 and 10 yrs, with EC and FO was remarkable, the oscillation between with EO and EC showed almost the same spectra for another groups. DISCUSSION: The length and areas of the trajectories were, reportedly, minimum around 40 yrs for the horizontal oscillation (Imaoka etal, Equilibrium Res Suppl 12, 1997). The vertical oscillation around 7 Hz with EC and FC for over 60 yrs was speculated to be aging. The vertical oscillation around 3 Hz with EC and FO below 10 yrs was speculated to be immature control for posture. [Jpn J Physiol 54 Suppl:S227 (2004)]