Motion analysis measurements of body movements during standing: association with age and sex.

The purpose of this study was to evaluate the association between balancing movements and age and sex in standing on two legs with the eyes open and closed using the motion analysis system. The collected data may help in developing balance evaluation and training in rehabilitation. The study sample consisted of 100 healthy, randomly selected people from the City of Oulu (men and women aged 31 to 80 years). The participants were divided into 10 groups by age decade and sex. The body movements in standing on two legs with the eyes open and closed were measured with the Mac Reflex motion analysis system (Qualisys AB, Partille, Sweden) and calculated as maximal anterior-posterior and total movements. The associations between movement values and age and sex were analysed. During standing on two legs with the eyes open, there was a statistically significant difference in the maximal anterior-posterior head movement between the age groups (P < 0.05) but the results did not show any other statistically significant differences between the balancing movements of the separate body parts of the groups or between the balance measurement values of men and women in standing on two legs with the eyes open and closed. In standing on two legs with the eyes closed all the measured body parts moved more than in standing with the eyes open (P < 0.001). It was concluded that healthy men and women seem to control their steady standing position with quite similar ranges of body adjustment. Standing balance control should also possibly be evaluated and trained in more difficult circumstances, because some changes do not necessarily appear in easier balance tasks or performance.