IMU 4 accelerometer 4 accelerometers 4 accelerometry 4 cerebral palsy 4 clinical 4 gait 4 gait analysis 4 gait rehabilitation inertial measurement unit 4 inertial measurement units 4 kinematics 4 locomotion 4 machine learning 4 motion capture 4 neurological disorders 4 older adults 4 physical activity 4 rehabilitation 4 stride length 4 stroke 4 validity 4 walking 4 wearable sensor 4 wearable sensors 4 3-axis force sensor 3 ANOVA analysis 3 Achilles tendon 3 ActiGraph 3 Alzheimer's disease 3