Influence of increased forward trunk tilt angle on stride length shortening during gait in older adults: Secondary analysis

Gait in older adults frequently entails augmented forward trunk tilt (FTT) and diminished hip extension, resulting in diminished stride length. However, the relationship between these factors remains unclear. The objective of this study was to verify the hypothesis that an augmented FTT angle impedes hip extension angles during gait, consequently diminishing stride length and walking speed. A secondary analysis was conducted using data from previous studies. The Microsoft Kinect V2 sensor was utilized to track the coordinates of the lower extremities and trunk during gait. Spatiotemporal variables, including walking speed and stride length, were calculated alongside peak FTT and hip extension angles. The optimal model, as indicated by the highest values for goodness-of-fit indices (goodness-of-fit index = 0.98, adjusted goodness-of-fit index = 0.91, comparative fit index = 0.98, root mean square error of approximation = 0.11), demonstrated that an augmented peak FTT angle results in a diminished peak hip extension angle during gait, consequently leading to a reduction in stride length and walking speed. In older adults, reduced walking speed is associated with shorter stride length, primarily due to decreased hip extension angle. The increased peak FTT angle contributes to this reduction in hip extension. To prevent decreases in walking speed, it is recommended that older adults engage in exercises that focus on trunk stabilization and hip extension.