Evidence map›Paper›PMID 42012517›Full record

ArticleEuropean journal of applied physiology2026

Gearing in the human medial gastrocnemius: effects of contraction conditions, tissue stiffness, and echo intensity.

Hiroko Yoshida, Masahide Yagi, Zimin Wang, Kohei Hirozawa, Hiroshige Tateuchi, Noriaki Ichihashi

Abstract read
PubMed Publisher
In one paragraph

Article in European journal of applied 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.

0numbers the graph read from it
0cells of the map it votes in
0citing papers in PubMed
–field-weighted citation impact
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

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

0 citing papers in PubMed.

No citing paper in PubMed yet.

4 · The record

Corrections and comments

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

6 authors.

Hiroko YoshidaHuman Health Sciences, Graduate School of Medicine, Kyoto University, 53 Kawahara- cho, Shogoin, Sakyo-ku, Kyoto, 606-8507, Japan.
Masahide YagiFaculty of Rehabilitation, Kansai Medical University, 18-89 Uyama Higashimachi, Hirakata, 573-1136, Osaka, Japan. yagi.masahide.5s@kyoto-u.ac.jp.ORCID http://orcid.org/0000-0002-1825-3570
Zimin WangHuman Health Sciences, Graduate School of Medicine, Kyoto University, 53 Kawahara- cho, Shogoin, Sakyo-ku, Kyoto, 606-8507, Japan.
Kohei HirozawaHuman Health Sciences, Graduate School of Medicine, Kyoto University, 53 Kawahara- cho, Shogoin, Sakyo-ku, Kyoto, 606-8507, Japan.
Hiroshige TateuchiHuman Health Sciences, Graduate School of Medicine, Kyoto University, 53 Kawahara- cho, Shogoin, Sakyo-ku, Kyoto, 606-8507, Japan.
Noriaki IchihashiHuman Health Sciences, Graduate School of Medicine, Kyoto University, 53 Kawahara- cho, Shogoin, Sakyo-ku, Kyoto, 606-8507, Japan.

Funding

Japan Society for the Promotion of Science 23K16572The Strategic Project for Proofreading and Submission Support of International Academic Papers" of Kansai Medical University The Strategic Project for Proofreading and Submission Support of International Academic Papers" of Kansai Medical University
6 · The paper itself

Abstract

purposeIn isolated animal muscles, contraction intensity and tissue stiffness have been shown to be related to gearing. However, these relationships remain poorly understood in humans. This study aimed to clarify how contraction intensity and velocity impact gearing and their relationship with tissue properties in humans.

methodsFifty-two healthy young adults participated in this study. We measured the shear elastic modulus of the medial gastrocnemius muscle, its aponeurosis, and the Achilles tendon, as well as muscle echo intensity. The shear elastic modulus of the aponeurosis was used for analysis as the ratio of transverse to longitudinal directions. Belly segment gear was quantified using ultrasound images of the medial gastrocnemius during isokinetic and isometric plantarflexion.

resultsDuring isometric contraction, belly segment gear under 60% MVC (1.054 ± 0.029) was significantly greater than that under 20% MVC (1.029 ± 0.044). In contrast, during isokinetic contraction, no significant difference between belly segment gear under 100°/s (1.053 ± 0.024) and that under 20°/s (1.056 ± 0.021) was observed. During lower-intensity, higher-velocity isokinetic contractions, greater belly segment gear was associated with a higher transverse to longitudinal stiffness ratio of the superficial aponeurosis (β = 0.274, p = 0.038), lower tendon stiffness (β=-0.312, p = 0.021), and lower echo intensity (β=-0.308, p = 0.021). Furthermore, mediation analysis revealed that the effect of aponeurosis stiffness on torque through belly segment gear was significant (indirect effect = 4.35; 95% confidence interval, 0.11-10.09).

conclusionBelly segment gear was associated with contraction intensity and connective tissue properties.

Indexed as

Isometric ContractionMuscle ContractionMuscle, SkeletalAchilles TendonAdultAponeurosisElastic ModulusFemaleHumansMaleUltrasonographyYoung AdultAponeurosisFascicle behaviorMuscle architecturePennation angleShear elastic modulus

Identifiers

What OpenQuestion holds

Textmetadata
Read underepoch 390

Registered trials

None linked

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.