Evidence map›Paper›PMID 42180827›Full record

ArticleFrontiers in physiology2026

Biomechanical effects of squatting movements in Tai Chi on the knee joint.

Haibin Liu, Wenxiao He, Guang Yang, Suheng Li, Liqing Liu, Fan Gao, Shudong Yan, Ziyang Wang, Fengjie Ran

Abstract read
In one paragraph

Article in Frontiers in physiology, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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0citing papers in PubMed
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1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

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3 · Its place in the literature

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4 · The record

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PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

9 authors.

Haibin LiuDalian Third People's Hospital Affiliated to Dalian University of Technology, Dalian, Liao Ning, China.
Wenxiao HeDalian Third People's Hospital Affiliated to Dalian University of Technology, Dalian, Liao Ning, China.
Guang YangDalian Third People's Hospital Affiliated to Dalian University of Technology, Dalian, Liao Ning, China.
Suheng LiSchool of Sports and Health Sciences, Dalian University of Technology, Dalian, Liao Ning, China.
Liqing LiuSchool of Sports and Health Sciences, Dalian University of Technology, Dalian, Liao Ning, China.
Fan GaoDepartment of Kinesiology and Health Promotion, University of Kentucky, Lexington, KY, United States.
Shudong YanSchool of Sports and Health Sciences, Dalian University of Technology, Dalian, Liao Ning, China.
Ziyang WangSchool of Sports and Health Sciences, Dalian University of Technology, Dalian, Liao Ning, China.
Fengjie RanDalian Third People's Hospital Affiliated to Dalian University of Technology, Dalian, Liao Ning, China.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

Background: Squatting is essential for daily activities but may risk knee injury due to excessive loads. Tai Chi squatting (TCS), characterized by slow, controlled movements, is hypothesized to reduce joint load compared to standard squatting (SS), though biomechanical comparisons remain scarce. This study aimed to biomechanically compare TCS and SS, with a focus on knee joint kinematics, kinetics, muscle activation, and internal stress distribution. Methods: Twelve experienced Tai Chi practitioners (6 males, 6 females) participated in this study. Participants performed TCS and SS in a controlled laboratory setting. Three-dimensional kinematics were captured with a VICON system, ground reaction forces were measured using AMTI force platforms, and muscle activation was recorded via surface electromyography (sEMG) using the Noraxon Ultium EMG system. The data were processed with an OpenSim musculoskeletal model, and finite element analysis was conducted using Ansys SpaceClaim and Ansys Workbench to evaluate internal knee joint stress distributions. Results: (1) Kinematics and Kinetics: Compared with SS, TCS produced a markedly smoother knee flexion-extension angle time profile (p < 0.001). TCS elicited significantly greater peak knee extension moments compared with SS (p < 0.001), particularly in male participants, and was associated with significantly elevated activation of the biceps femoris and sartorius, reflecting a shift toward posterior chain co-activation, resulting in a more balanced quadriceps-to-hamstring co-activation pattern. This tendency was particularly pronounced in female participants (p < 0.05). (2) Finite Element Stress Analysis: While the absolute difference in peak Von Mises stress on the femoral cartilage between SS and TCS was modest, TCS produced a qualitatively more homogeneous stress distribution across the articular surface, with the focal high-stress concentration pattern observed under SS notably attenuated. This improvement in load distribution morphology may carry greater functional relevance for long-term cartilage health than peak stress magnitude alone. Conclusion: TCS promotes more balanced muscle co-activation and a more homogeneous intra-articular stress distribution compared with SS, potentially reducing the risk of localized cartilage fatigue, particularly in female practitioners. These findings support the integration of TCS into rehabilitation and conditioning programs.

Indexed as

finite element analysisknee joint biomechanicssex differencessquatTai Chi

Identifiers

PMID42180827
PMCPMC13194051

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LicenceCC BY
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Registered trials

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.