Abstract
Background: Balance deterioration in older adults limits their activities of daily living, community participation, and is a significant risk factor for falls. One contributory element to this functional decline is impairment of anticipatory postural adjustments (APAs).
Objectives: To evaluate the role and feasibility of a novel training program in improving APAs for balance control of older adults.
Method: Six older adults (73.3±5.0 years) were randomly assigned into the Experimental (EG) and Control groups (CG). The EG participated in four weeks of APA-focused training involving catching a medicine ball while standing. All subjects were exposed to predictable external and self-initiated perturbations before and after training. EMG activity of eight trunk and leg muscles was recorded bilaterally and muscle onsets were analyzed during the anticipatory phase of postural control. Clinical tests of balance (Timed-Up and Go, Single limb stance, and Activities-specific Balance Confidence scale) were implemented.
Results: Early onsets of APA activity prior to the external perturbations were seen in the EG following training. Moreover, early APA activity was observed in the EG prior to bilateral arm flexion, a task that was not a part of training, indicating a transfer of the learning effect of training. The improvement of APAs in the EG also resulted in improved performance on clinical outcome measures. There were no improvements seen in the CG for both the APA activity and the clinical balance tests.
Conclusion: The study outcome suggests that a four-week APA-based training program is feasible and could be effective in improving postural control, functional balance, mobility, and quality of life in older adults.
Keywords: Balance control, anticipatory postural adjustments, older adults, training, ball catching, rehabilitation.