Stability during Stairmill Ascent with Upward and Downward Applied Forces on the Pelvis
Journal
IEEE Transactions on Neural Systems and Rehabilitation Engineering
Journal Volume
29
Pages
1504-1512
Date Issued
2021
Author(s)
Chang B.-C.; Agrawal S.K.
DOI
ITNSB
Abstract
This study investigates how external vertical forces on the pelvis change the stability of stairmill climbing and other gait parameters such as kinematics and muscle activity. We use a Tethered Pelvic Assist Device (TPAD) to apply forces on the pelvis during continuous ascent on a stairmill. Ten young healthy subjects participated in three one-minute stair ascent with no force, a 10% body weight (BW) downward force, and a 10% BW upward force applied on the pelvis. The stability is determined by evaluating the base of support (BoS) and margin of stability (MoS). Kinematics and muscle activities were used to characterize the biomechanical changes. The results show that the upward forces applied on the pelvis decreased the (i) MoS by 1.84cm in the lateral direction, 2.07cm in the anterior direction, (ii) double stance phase by 1.85%, and (iii) the knee flexion by 5°. Furthermore, the peak activation levels of the muscles rectus femoris (RF), vastus lateralis (VL), and left gastrocnemius decreased. In contrast, the downward forces applied on the pelvis increased (i) the MOS by 1.5cm in the anterior direction and (ii) mean activation levels of RF and VL muscles. This study provides insights into the effects of applied vertical forces on the pelvis during stair ascent. These findings contribute to the understanding of the gait parameter changes and their relation with stability. Results could be used as a basis for designing training protocols to improve balance during stair ascent. © 2001-2011 IEEE.
Subjects
Chemical activation; Kinematics; Muscle; Physiological models; Stairs; Activation level; Applied forces; Base of supports; Biomechanical changes; Gait parameters; Healthy subjects; Lateral directions; Muscle activities; Stability; adult; article; body weight; clinical article; controlled study; female; foot; gait; gastrocnemius muscle; human; human experiment; kinematics; knee function; male; muscle function; pelvis; rectus femoris muscle; stair climbing; standing; vastus lateralis muscle; biomechanics; gait; knee; pelvis; skeletal muscle; walking; Biomechanical Phenomena; Gait; Humans; Knee Joint; Muscle, Skeletal; Pelvis; Walking
Publisher
Institute of Electrical and Electronics Engineers Inc.
Type
journal article