Differences In Lower Extremity Muscle Activation Are Characteristic Between Curves And Straight Paths In Older Adults

PURPOSE: In daily life, walking in a curved path is more likely to cause a fall than walking in a straight path. Although there has been extensive research on the gait of older adults while walking, there is limited reporting on the characteristics of lower limb muscle activation. This study aims to analyze the differences in lower limb muscle activation characteristics in healthy older adults while walking in curved and straight paths. METHODS: 12 healthy older adults (aged 68 ± 2 years) were recruited from the community. Participants were required to walk in a straight line or a figure-of-8 pathway randomly. Each gait cycle was divided into four phases: the first double support, right single support, the second double support, and the left single support stages. In the figure-of-8 walking, the integrated electromyography (EMG) mean values of the rectus femoris, biceps femoris, gastrocnemius, and tibialis anterior muscles on bilateral lower limbs were analyzed when walking to the right. The paired sample t-test was used to examine the differences in the parameters, with p < 0.05 considered statistically significant. RESULTS: Compared to straight walking, when the older adults continuously turned to the right, during the first double support phase, the values of the tibialis anterior, right biceps femoris, and left biceps femoris were greater (p < 0.02); during the right single support phase, the value of the right biceps femoris was greater (p = 0.011); during the second double support phase, the values of the right tibialis anterior, right biceps femoris, left gastrocnemius, and left tibialis anterior were greater (p < 0.04); during the left single support phase, the value of the left tibialis anterior was smaller (p = 0.02). CONCLUSIONS: Compared with walking in a straight line, except during the left single support phase, older adults exhibit motion-related activation characteristics in the supporting leg muscles when continuously turning to the right. During the left single support phase, apart from the left tibialis anterior, there is little difference in muscle activation between continuously turning and straight walking. National Natural Science Foundation of China (12102235)