To compare gait parameters during single-task and dual-task walking in older adults, and to examine differences in dual-task costs between individuals with high versus low balance abilities under different task conditions.

From November to December 2024, community-dwelling older adults were recruited through Hebei Province's national physical fitness monitoring network across multiple communities in Shijiazhuang and Xiong'an New Area. An inertial sensor-based gait analysis system was used to collect spatiotemporal gait parameters during three conditions: single-task walking, motor dual-task walking (simultaneous carrying task), and cognitive dual-task walking (serial subtraction task). Participants were stratified into high-balance and low-balance groups based on median eyes-closed single-leg stance duration (cut-off: 18.40 seconds). Dual-task costs (DTC) were calculated and compared between groups.

The study included 133 eligible participants[30 male, 103 female; mean age (66.95±4.75) years]. The low-balance group 66 participants, and the high-balance group 67 participants. Compared to single-task walking, motor dual-task conditions significantly increased stride time and double support phase duration (all P < 0.05), while decreasing stride length, gait velocity, and cadence (all P < 0.05). Cognitive dual-task conditions prolonged all temporal parameters (stride time, single/double support, swing time; all P < 0.05) and reduced spatial parameters (stride length, velocity, cadence; all P < 0.05). Under the dual-task intervention condition, compared to the low-balance group, the high-balance group exhibited an increase in single support time cost (0.35% vs. -1.51%, P=0.019) and swing time cost (0.33% vs. -1.20%, P=0.044), along with a reduction in stride frequency cost (-0.85% vs. 0.14%, P=0.042).

While dual-task conditions generally impair gait parameters in older adults, individuals with higher balance abilities maintain more stable gait patterns during motor dual-tasks, demonstrating greater resilience to interference. These findings highlight the importance of balance capacity in preserving functional mobility during daily multitasking activities.