Artificial Life and Robotics

, Volume 20, Issue 1, pp 42–48 | Cite as

Simple tai chi exercise for improving elderly postural stability via complexity index analysis

  • Cheng-Wei Huang
  • Wei-Hsin Chen
  • Heng-Hui Chu
  • Bernard C. Jiang
  • Maysam Abbod
  • Jiann-Shing ShiehEmail author
Original Article


The main purpose of this study is to investigate twice a day simple 9-step tai chi effects of the center of pressure (COP) and physiological signals of elderly people. Data are collected from the COP signals, electromyography (EMG), and pulse oximetry for 1 min for the period of 12 weeks. The COP signals are analyzed using multivariate empirical mode decomposition and multivariate multiscale entropy to work out and compare the complexity index (CI). Subjects in this experiment are over 65 years old who are divided into 11 men and 7 women; the average age is 74 ± 8.18 years. In conclusion, it is found that tai chi exercise can improve human body balance by just walking some simple steps in our experiment. However, we cannot find any effect or improvement in the pulse oximetry and EMG signals analysis.


Center of pressure (COP) Electromyography (EMG) Multivariate empirical mode decomposition (MEMD) Multivariate multiscale entropy (MMSE) Complexity index (CI) Six-minute walk test Time-up-and-go Tai chi 



This research is supported by Ministry of Science and Technology in Taiwan through Grant number of NSC102-2221-E-155-028-MY3. This research is also supported by the Center for Dynamical Biomarkers and Translational Medicine, National Central University, Taiwan which is sponsored by Ministry of Science and Technology (NSC102-2911-I-008-001).


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Copyright information

© ISAROB 2014

Authors and Affiliations

  • Cheng-Wei Huang
    • 1
  • Wei-Hsin Chen
    • 2
  • Heng-Hui Chu
    • 1
  • Bernard C. Jiang
    • 3
  • Maysam Abbod
    • 4
  • Jiann-Shing Shieh
    • 1
    • 5
    • 6
    Email author
  1. 1.Department of Mechanical EngineeringYuan Ze UniversityChung-LiTaiwan
  2. 2.Department of Industrial Engineering and ManagementYuan Ze UniversityChung-LiTaiwan
  3. 3.Department of Industrial ManagementNational Taiwan University of Science and TechnologyTaipeiTaiwan
  4. 4.School of Engineering and DesignBrunel UniversityLondonUK
  5. 5.Innovation Center for Big Data and Digital ConvergenceYuan Ze UniversityChung-LiTaiwan
  6. 6.Center for Dynamical Biomarkers and Translational MedicineNational Central UniversityChung-LiTaiwan

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