Effect of visual acuity in older females on energy expenditure during obstacle navigation

Objectives: To investigate the effects of good and poor visual acuities in older females on energy expenditure during obstacle navigation under different three conditions. Methods: Nineteen older females living in the community were enrolled in the present study. Ten participants had a binocular visual acuity worse than or equal to 0.4 (logarithm of the minimum angle of resolution (logMAR) (poor binocular visual acuity [PBVA]) and the other nine had a binocular visual acuity better than or equal to 0.3 logMAR (good binocular visual acuity [GBVA]). An accelerometer was attached over the L3 spinous process and each participant walked at a self-determined speed, under three different conditions (bare foot, wearing socks, and navigating obstacle while wearing socks) on a GAITRite (R) mat. Differences in gait velocity and energy expenditure were analyzed using the independent t-test for comparisons between groups. The gait velocity and energy expenditure of the GBVA and PBVA groups, derived under the three test conditions, were analyzed via one-way repeatedmeasures analysis of variance. Results: The gait velocity of the GBVA group was significantly faster than that of the PBVA group under the bare foot, wearing socks, and navigating obstacles while wearing socks. Whereas the energy expenditure of the GBVA group was significantly less than that of the PBVA group under the bare foot, wearing socks, and navigating obstacles while wearing socks. In addition, the gait velocity and energy expenditure of the groups differed significantly among the three experimental conditions. Conclusions: The present study suggests that visual acuity in the older female influences both gait velocity and energy expenditure during obstacle gait. In addition, elderly subjects with PBVA exhibited inefficient walking patterns compared with those with GBVA, remarkably when foot sensory input was distorted and obstacles were present. (C) 2016 Elsevier Masson SAS and European Union Geriatric Medicine Society. All rights reserved.