Tai Chi Improve Postural Control Among Older Adults During Stair Descenting With Low-lighting Condition

Ran Chen1, Li Li2(FACSM), Qipeng Song11Shandong Sport University, Jinan, China2Georgia Southern University, Statesboro, GA, USA, [email protected]. PURPOSE: Older adults are prone to stair descent falls without adequate lighting. Tai Chi, as a traditional Chinese conditioning exercise, has been proven to improve postural control by altering body condition, gait, and proprioception. This study investigated whether Tai Chi exercise could improve postural control during stair descent under low-lighting conditions. METHODS: A total of 30 older females practicing Tai Chi (TC) and brisk walking (BW) were included and assigned to TC (n = 15; age: 66.3 ± 2.5 years; height: 162.8 ± 2.7 cm; body mass: 62.3 ± 8.4 kg; and TC experience: 8.4 ± 2.8 years) and BW (n = 15; age: 68.6 ± 4.2 years; height: 161.4 ± 3.8 cm; body mass: 62.1 ± 9.7 kg; and BW experience: 6.8 ± 3.6 years) groups. Each participant was asked to complete one testing session per day for a total of three testing sessions. In each session, the participants were asked to descend the staircase step under low-lighting condition (3Lx). The order of illumination was randomized by a Latin Square method. The illumination system was mounted on the ceiling and was composed of 48 LEDs with separate switches. During each session, they were then asked to walk for 400 m at a self-selected speed as a level walking test before the stair descent test. During the stair descent test, the participant was asked to perform five successful stair descent trials. The participants had 1 minute to rest after each trial. An eight-camera motion capture system recorded their motions at 100 Hz. Their trunk inclination angle, COM sway in the mediolateral (ML) direction, and foot clearance were calculated. Independent t-tests were used to detect group differences. RESULTS: Under low-lighting, TC group had a lower trunk inclination angle (TC = 10.2 ± 3.0°, BW = 11.1 ± 3.6°, p = 0.042), smaller COMML sway (TC = 22.1 ± 8.9 mm, BW = 32.3 ± 10.7 mm, p = 0.015), and a higher foot clearance (TC = 125.9 ± 41.1 mm, BW = 100.9 ± 36.7 mm, p = 0.035) than the BW group. CONCLUSION: TC participants have better postural control under low-lighting condition than those who practiced BW.