ABSTRACT
BACKGROUND: balance control is a major problem for older individuals with poor vision. There are limitations, however, for visually impaired elderly persons wishing to participate in exercise programmes. The benefits of Tai Chi for balance control, muscle strength and preventing falls have been demonstrated with sighted elderly subjects. This study was designed to extend those findings to elderly persons with visual impairment. OBJECTIVE: to investigate the effects of Tai Chi on the balance control of elderly persons with visual impairment. DESIGN: randomised clinical trial. SETTING: residential care homes. SUBJECTS: forty visually impaired persons aged 70 or over. METHODS: the participants were randomly divided into Tai Chi and control groups and assessed pre- and post-intervention using three tests: (i) passive knee joint repositioning to test knee proprioception; (ii) concentric isokinetic strength of the knee extensors and flexors and (iii) a sensory organisation test to quantify an individual's ability to maintain balance in a variety of complex sensory conditions. RESULTS: after intervention, the Tai Chi participants showed significant improvements in knee proprioception and in their visual and vestibular ratios compared with the control group. CONCLUSION: practicing Tai Chi can improve the balance control of visually impaired elderly persons.
Subject(s)
Postural Balance , Tai Ji , Vision Disorders/therapy , Vision, Ocular , Aged , Aged, 80 and over , Chi-Square Distribution , Female , Homes for the Aged , Hong Kong , Humans , Knee Joint/physiopathology , Male , Multivariate Analysis , Muscle Strength , Proprioception , Recovery of Function , Single-Blind Method , Time Factors , Treatment Outcome , Vestibule, Labyrinth/physiopathology , Vision Disorders/physiopathologyABSTRACT
Good balance, an important ability in controlling body movement, declines with age. Also, balance appears to decrease when visual input is restricted, while this has been poorly investigated among visually impaired very old adults. The objective of this study is thus to explore whether the balance control of the very old differs with varying degrees of visual impairment. This cross-sectional study was conducted in community centers and residential care homes. Thirty-three visually impaired (17 = low vision; 16 = blind) and 15 sighted elderly aged ≥ 70 years participated in the study. All participants were assessed: (1) concentric isokinetic strength of the knee extensors and flexors; (2) a sensory organization test to measure their ability to use somatosensory, visual, and vestibular information to control standing balance; (3) a perturbed double-leg stance test to assess the ability of the automatic motor system to quickly recover following an unexpected external disturbance; (4) the five times sit-to-stand test. Compared with low-vision subjects, the sighted elderly achieved higher peak torque-to-body weight ratios in concentric knee extension. The sighted elderly showed less body sway than the low vision and blind subjects in sensory conditions where they benefited from visual inputs to help them maintain standing balance. The sighted and low-vision subjects achieved smaller average body sway angles during forward and backward platform translations compared to the blind subjects. Low vision and blindness decrease balance control in elderly.