Walking more slowly than with normal velocity: The influence on trunk and pelvis kinematics in young and older healthy persons.

BACKGROUND: Few studies have addressed trunk and pelvis movements during gait, although they play an important role in gait control. The aim of this study was to compare trunk and pelvis kinematics between slower walking (1, 2, 3, 4kmph) and normal walking (5kmph), and between healthy adults who were young (n=15, 20-30years) and older (n=17, 50-60years).

METHODS: After 4min of treadmill walking, the 3-dimensional trunk and pelvis kinematics was measured (Polhemus Liberty™, 250Hz). A repeated measures ANOVA with simple contrasts was used to look for differences between the velocity conditions of walking and independent t-testing for comparison between the age groups (significance level: 5%, SPSS20).

FINDINGS: Walking more slowly than with normal velocity induces (1) a decrease in vertical center of mass of the trunk displacement, trunk lateral flexion and axial rotation and pelvis lateral and antero-posterior tilting, and (2) an increase in lateral and antero-posterior center of mass of the trunk displacement. Compared to young persons, older persons show: (1) larger pelvis axial rotations and trunk lateral and antero-posterior movements, and (2) smaller pelvis lateral tilting and trunk vertical movements and rotations.

INTERPRETATION: The literature reports that patients often walk slowly and that older persons show different gait patterns compared to young persons. This study shows that there are changes in trunk and pelvis kinematics (1) when walking more slowly than with normal velocity and (2) in older persons compared to young persons. These data could be taken into account in gait rehabilitation.