EFFECT OF AGE AND TRAINING SCHEDULES ON BALANCE IMPROVEMENT EXERCISESUSING VISUAL BIOFEEDBACK

There has been a growing popularity and success rate of balance rehabi litation programs, and this success is paralleled by the growth of tec hnology, making available instruments that provide objective, quantita tive, and immediate results. The Balance Master(TM) is such a commerci ally available instrument, consisting of a dual-force platform connect ed to a microcomputer that provides visual feedback of the centre of g ravity (COG) in relation to the theoretical limits of stability. Spont aneous body sway can be measured in a static central position, or in p eripheral positions around the limits of stability (peripheral sway ar ea). The trajectory between targets can also be analyzed in terms of t ime (transition time) and accuracy (path error) of transition, which g ives a quantitative measure of dynamic movement of the COG. This study examined the practice effect that occurs while using this instrument over repeated sessions for two schedules of training (daily and weekly ) and over two age groups (20-35 years, and 60-75 years). Each group c ompleted a series of postural exercises, with an assessment of static and dynamic postural variables before and after training, and at appro ximately 3 and 6 weeks posttraining. Spontaneous body sway was measure d with eyes open, eyes closed, and with visual feedback of the COG. No significant changes were observed in these variables as measured over the four standard assessment occasions. Peripheral sway area and path error decreased significantly for both the daily and weekly training groups from pre- to post-training, and these skills were retained over both retention tests, whereas the tendency toward decreasing transiti on time was not significant. There were no significant differences bet ween the daily and the weekly training groups. For the elderly group, transition time was the variable with the largest improvement, while p ath error and peripheral sway area exhibited no significant change. Th ese results identify task-specific training effects with repeated prac tice for a normal population. Also, variables introduced by the Balanc e Master system are novel, and these results help to determine which o f these measures change with practice. This varies with age. These ide ntified differences may be relevant to the tendency of older healthy p eople to fall.