Effects of low light on the stability of the head and pelvis of the healthy elderly

[Purpose] The purpose of this study was to evaluate the changes in body stability of the elderly while walking on even surface ground under low light. [Subjects] Ten young males and ten elderly males participated in this experiment. [Methods] Each subject walked along a 7 m walkway five times at their preferred walking speed under normal (>300 lux, NORM) and low light conditions (<5 lux, LOW). To compare the changes in body stability, the root mean square of acceleration (RMSacc) at the head and pelvis was used. [Results] The results show that the body stability of young adults showed a similar RMSacc in all directions at the head and pelvis between the normal and low light walking conditions. In contrast, the RMSacc in all directions at the head and pelvis during low light walking by elderly adults was significantly greater than that of normal light walking. [Conclusion] It was confirmed that, despite walking on even ground, low light condition affects the body stability of the elderly. To clearly evaluate the effect of low light with aging on gait pattern, further study will be necessary to perform additional experiments under various environmental conditions to investigate walking speed, multi-tasking, stairs, and uneven walkway performance.