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Abstract
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OBJECTIVES
To investigate the effects of square turning (ST) and semicircular turning (SCT) on gait velocity and center of mass (COM) acceleration while ambulating in elderly women with good binocular visual acuity (GBVA) and poor binocular visual acuity (PBVA). We also compared balance recovery after turning within visual acuity groups.
Methods
The present study enrolled 22 community-living elderly Korean women. The BVA of 11 participants were less than or equal to 0.4 logarithm of the minimum angle of resolution (logMAR), and the others were better than or equal to 0.3 logMAR. Participants walked at a self-selected speed along a marked path that included two types of turns (consist of three segment: straight, turning, return straight) while fitted with an accelerometer over the L3 spinal process. Gait velocity and COM acceleration were measured using a tri-axial accelerometer. Balance recovery after turning was indexed by comparison of the gait velocity and normalized COM acceleration of the straight and return-straight stages of sharp (ST) and less-sharp (SCT) turns.
Results
The velocity was significantly faster and normalized medial-lateral (ML) COM acceleration was lower during the three segments of the ST and SCT courses in the GBVA group compared with that of PBVA group. In addition, the velocity in both groups during turning segment significantly decreased and velocity of GBVA group was significantly recovered after turning only SCT course whereas velocity of PBVA was not recovered on both courses. Normalized anterior-posterior (AP) COM in GBVA group significantly decreased during turning and return straight segment compare to straight segment on ST course. PBVA group showed different AP COM between straight and return straight segments on ST course. Normalized (ML) COM acceleration of the both groups during turning and return straight segment on SC course was significantly decreased compare to straight segment.
Conclusions
We found that visual acuity affected gait velocity and balance in older adults. Those with PBVA exhibited more cautious walking strategies, including slower gait velocity and fluctuated ML COM motion, to overcome the difficulty posed by turning while walking. Those with GBVA recovered balance more quickly after less sharp turns. Changing direction while walking is one of the biggest challenges for elderly, even those with good visual acuity and especially, older adults with PBVA require balance and gait training using a variety of turns to prevent falls.
Language: en |