title: Effect of active arm swing to local dynamic stability during walking.
abstract: Arm swing is an essential component in regulating dynamic stability of the whole body during walking, while the contribution of active arm swing to local dynamic stability of different motion segments remains unclear. This study investigated the effects of arm swing under natural arm swing condition and active arm swing condition on local dynamic stability and gait variability of the trunk segments (C7 and T10 joint) and lower extremity joints (hip, knee and ankle joint). The local divergence exponents (λs) and mean standard deviation over strides (MeanSD) of 24 young healthy adults were calculated while they were walking on treadmill with two arm swing conditions at their preferred walking speed (PWS). We found that in medial-lateral direction, both λs and MeanSD values of the trunk segments (C7 and T10 joint) in active arm swing condition were significantly lower than those in natural arm swing condition (p<0.05), while no significant difference of λs or MeanSD in lower extremity joints (hip, knee and ankle joint) was found between two arm swing conditions (p>0.05, respectively). In anterior-posterior and vertical direction, neither λs nor MeanSD values of all body segments showed significant difference between two arm swing conditions (p>0.05, respectively). These findings indicate that active arm swing may help to improve the local dynamic stability of the trunk segments in medial-lateral direction.
authors.affiliation: School of Biomedical Engineering, Shanghai Jiaotong University, Shanghai, China; Engineering Research Center of Digital Medicine and Clinical Translation, Ministry of Education of P.R. China, Shanghai, China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Wu
authors.affiliation: Technology R & D Team, Toronto Rehabilitation Institute, University Health Network, Toronto, Canada.
authors.forename: Yue
authors.initials: Y
authors.lastname: Li
authors.affiliation: School of Health Sciences, University of Salford, Manchester, United Kingdom.
authors.forename: An-Min
authors.initials: AM
authors.lastname: Liu
authors.affiliation: Engineering Research Center of Digital Medicine and Clinical Translation, Ministry of Education of P.R. China, Shanghai, China; Department of Orthopedic Surgery & Shanghai Key Laboratory of Orthopaedic Implant, Shanghai Ninth People's Hospital of Shanghai Jiaotong University School of Medicine, Shanghai, China.
authors.forename: Fei
authors.initials: F
authors.lastname: Xiao
authors.affiliation: Engineering Research Center of Digital Medicine and Clinical Translation, Ministry of Education of P.R. China, Shanghai, China; Department of Orthopedic Surgery & Shanghai Key Laboratory of Orthopaedic Implant, Shanghai Ninth People's Hospital of Shanghai Jiaotong University School of Medicine, Shanghai, China.
authors.forename: Yin-Zhi
authors.initials: YZ
authors.lastname: Wang
authors.affiliation: School of Biomedical Engineering, Shanghai Jiaotong University, Shanghai, China; Engineering Research Center of Digital Medicine and Clinical Translation, Ministry of Education of P.R. China, Shanghai, China.
authors.forename: Fei
authors.initials: F
authors.lastname: Hu
authors.affiliation: School of Biomedical Engineering, Shanghai Jiaotong University, Shanghai, China; Engineering Research Center of Digital Medicine and Clinical Translation, Ministry of Education of P.R. China, Shanghai, China.
authors.forename: Jin-Ling
authors.initials: JL
authors.lastname: Chen
authors.affiliation: School of Biomedical Engineering, Shanghai Jiaotong University, Shanghai, China; Engineering Research Center of Digital Medicine and Clinical Translation, Ministry of Education of P.R. China, Shanghai, China; Department of Orthopedic Surgery & Shanghai Key Laboratory of Orthopaedic Implant, Shanghai Ninth People's Hospital of Shanghai Jiaotong University School of Medicine, Shanghai, China.
authors.forename: Ke-Rong
authors.initials: KR
authors.lastname: Dai
authors.affiliation: School of Biomedical Engineering, Shanghai Jiaotong University, Shanghai, China; Engineering Research Center of Digital Medicine and Clinical Translation, Ministry of Education of P.R. China, Shanghai, China; Department of Orthopedic Surgery & Shanghai Key Laboratory of Orthopaedic Implant, Shanghai Ninth People's Hospital of Shanghai Jiaotong University School of Medicine, Shanghai, China. Electronic address: dongyungu@sjtu.edu.cn.
authors.forename: Dong-Yun
authors.initials: DY
authors.lastname: Gu
mesh_terms: D000328:Adult; D000843:Ankle Joint / Q000502:physiology; D001132:Arm / Q000502:physiology*; D005080:Exercise Test; D005260:Female; D005684:Gait / Q000502:physiology; D006801:Humans; D007719:Knee Joint / Q000502:physiology; D008297:Male; D009043:Motor Activity / Q000502:physiology*; D004856:Postural Balance / Q000502:physiology*; D016138:Walking / Q000502:physiology*; D055815:Young Adult
keywords: Arm swing; Gait; Local divergence exponent; Local dynamic stability