A Comparison of the Gait Harmonic Ratio between Faller and Non-faller Iranian Older Adults, under Single-task and Dual-task Conditions

Performing a secondary task while maintaining postural control can aggravate balance impairments among older individuals. The present study aimed to compare the gait harmonic ratio between faller and non-faller community-dwelling older adults. In this cross-sectional study, 20 faller older adults (13 females and 7 males) and 20 non-faller older adults (12 females and 8 males) were recruited from the members of a retirement center. Before the trial, a medical code of ethics was granted and the written consent forms were signed by all participants. The variable, the gait harmonic ratio in medial-lateral, vertical, and anterior-posterior directions under single-task and dual-task conditions, was measured using an accelerometer. Under the single-task condition, there was no statistically significant difference between the faller and non-faller groups in any direction of gait harmonic ratio. Under the dual-task condition, the faller group revealed significantly lower harmonic ratios in medial-lateral (p < /em>=0.010) and vertical (p < /em>=0.032) directions compared to the non-faller group. However, no statistically significant difference was reported between the two groups for the anterior-posterior direction in dual-task walking. The findings of the present study indicated that the medial-lateral and vertical gait harmonic ratios can considerably be affected under dual-task conditions in faller older individuals.