Author: Hao Yu1, JiangNa Wang1, Min Mao2, QiPeng Song1, Cui Zhang3, Daniel T P Fong4, Wei Sun1
Affiliation: <sup>1</sup> College of Sports and Health, Shandong Sport University, Jinan, China.
<sup>2</sup> School of Nursing and Rehabilitation Shandong University, Jinan, China.
<sup>3</sup> Lab of Biomechanics, Shandong Institute of Sport Science, Jinan, China.
<sup>4</sup> National Centre for Sport and Exercise Medicine, School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, UK.
Conference/Journal: Res Sports Med
Date published: 2021 Dec 26
Other:
Special Notes: doi: 10.1080/15438627.2021.2020788. , Word Count: 207
This study aimed to investigate the co-contraction and pre-activation of agonistic and antagonistic muscles in experienced Tai Chi (TC) practitioners during normal walking (NW) and brush-knee twist-step (BKTS). The electromyographic activities of rectus femoris, biceps femoris, and tibialis anterior and lateral gastrocnemius muscles were collected during BKTS and NW in 28 TC practitioners. The pre-activation of knee and ankle joints before initial landing of left foot, and the co-contraction of knee and ankle joint in double-stance phase I (DSI), single-stance phase (SS), double-stance phase II (DSII), and swing phase (SW) were calculated during BKTS and NW. Ankle co-contraction significantly increased during DSI and SS in BKTS movements than compared with that in NW. For DSI and SW, SS and DSII, and DSII and SW, a significant difference was found in BKTS. The pre-activation of knee joint significantly decreased in BKTS and NW. This study indicated greater ankle joint muscle co-contraction in DSI and SS of stance phase and lower knee joint muscle co-contraction and pre-activation than in NW in BKTS movement. In addition, greater ankle joint muscle co-contraction was observed in the DSI, SS, and DSII of stance phase than those of swing phase in BKTS movement.
Keywords: Tai Chi; brush-knee twist-step; co-contraction; normal walking; pre-activation.
PMID: 34957881 DOI: 10.1080/15438627.2021.2020788