Major Characteristics Of Gait Pattern In Elderly Adults Based On Kinematics Analysis

Gait is the pattern of movement of the lower limbs during walking.Kinematics,the recording and description of motion during locomotion,is the key area of gait analysis.With the rapid development of micro electro mechanical system,the portable and wearable inertial moment unit(IMU)sensor,which combines 3 dimensional acceleration,3 dimensional gyroscope data,has been used for motion capture and gait analysis.The advantages of these IMU sensors are free of environmental limitation and low cost compared to the infra-red motion capture system.IMU sensors were used in the present study to analyse the major kinematics characteristics of the gait pattern during different walking speeds in elderly participants.It is important for the elderly people to maintain good walking ability for their daily activities.Kinematics analysis in health older adults would facilitate objective and accurate evaluation of gait and help designing appropriate walking programs for elderly people.We invited 35(18 female: 64±3 age,159.7±5.2cm height,60.4±5.6kg weight;17 male: 66±2 age,172.0±4.9cm height,76.3±12.4kg weight)retired staff from Dalian University of Technology to participate our study.The selected walking speeds are closely related to their daily life.Slow speed represents the comfortable speed,the medium speed refers to the safe speed to cross the traffic lights,and the fast speed is related to the brisk walking speed.The participants walked 6 minutes at the 3 target speed on a treadmill.The 5 IMU sensors were attached to the back,the centre of gravity,thigh,calf,and foot.The O2,CO2,and heart rate(HR)data were also collected during the walking tests by using MetaLyzer 3B pulmonary functional analyser.The Delsys EMMA software and quaternion algorithm were used to analyse the joint angles,such as hip internal/external rotation,hip adduction/abduction,hip flexion/extension,knee flexion/extension,ankle internal/external rotation,ankle flexion/extension,and foot adduction/abduction.The step cadence and stride length were also calculated by finding the peaks of each gait cycle.The energy expenditure(EE)and MET were calculated based on classical methods.The general linear model was conducted to compare the effects of walking speed and gender on the range of motions(ROM)of these 7 joint angles,step cadence,stride length,EE,MET,and HR.The results show that the hip adduction/abduction ROM is increased significantly with increased walking speed,and differ significantly between female and male participants.The ROM of Hip rotation and knee flexion/extension were significantly higher in female participants than in male participants during walking.On the other hand,the stride length of male participants is significantly longer than female participants,whereas the cadence of male participants is significantly lower than female participants.This suggests that the female participants tend to use higher cadence to keep up when the required speed is high,however,the male participants would use longer stride length for fast walking speed.The EE,MET and HR increases with increased walking speed.Male participants consume more energy than female participants,this might due to male participants have more muscle mass.The HR is significantly higher in female participants than in male participants.Except the ROM of hip adduction/abduction,we found no significant differences in ROM for the lower limb joint angles between walking speed,which indicate that the brisk walking is a safe way of exercise.For the perspective of EE and MET,the EE and MET of brisk walking is in the zone recommended by the American College of Sports Medicine,which suggest that brisk walking is an effective exercise as well.