Evidence map›Paper›PMID 41889795›Full record

ArticleFrontiers in physiology2026

Exploring performance-related inter-limb asymmetry thresholds in speed skating: a CART analysis approach.

Zhiyong Jin, Yufeng Wang, Chunyuan Yang, Yuzi Diao, Li Yan

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Article in Frontiers in physiology, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 1 paper.

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1citing papers in PubMed
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1 citing paper in PubMed.

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5 · Who and what money

Authors and funding

5 authors.

Zhiyong JinHarbin Sport University, Harbin, China.
Yufeng WangHarbin Sport University, Harbin, China.
Chunyuan YangHarbin Sport University, Harbin, China.
Yuzi DiaoHarbin Sport University, Harbin, China.
Li YanHarbin Sport University, Harbin, China.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

Long-term specialized training can lead to increased inter-limb asymmetry in speed skaters. While excessive inter-limb asymmetry may impair athletic performance, its impact on different skating phases and the corresponding thresholds remain unclear. The objective of this study was to investigate the relationship between lower limb strength asymmetry and split skating times, and to identify corresponding asymmetry thresholds using a data-driven Classification and Regression Tree (CART) analysis. Thirty-nine adolescent male speed skaters (age: 16.85 ± 0.81 years, height: 177.45 ± 4.26 cm, body mass: 66.03 ± 5.60 kg) underwent inter-limb asymmetry assessments based on single-leg vertical drop jump (SVDJ) and single-leg lateral squat jump (SLSJ) tasks. Skating performance was evaluated via a 500 m time trial, where split times for the start (20 m), straight (100 m), and curve phases (110-200 m), as well as the total time were recorded. Results showed that SVDJ jump height asymmetry explained 19.70% of the variance in 20 m start time (F(1, 37) = 9.07, p = 0.005). Moreover, in conjunction with SLSJ performance asymmetry, it explained 20.95%-24.65% of the variance in 100 m straight time (Best λ = 0.04, root mean squared error (RMSE) = 0.27) and 500 m total time (Best λ = 0.12, RMSE = 1.07). The CART analysis identified asymmetry in SVDJ jump height and SLSJ take-off velocity as the optimal variables (defined by the lowest RMSE) for distinguishing skating performance, with thresholds of 12.07% (RMSE = 0.15) and 10.26% (RMSE = 0.49), respectively. Independent samples t-tests revealed significant differences in split skating time between the high- and low-asymmetry groups defined by these thresholds (p < 0.01, Hedges' g = 1.10-1.44). Exceeding asymmetry thresholds for SVDJ jump height and SLSJ take-off velocity may negatively affect start, straight and 500 m total skating times in adolescent male speed skaters. This inter-limb asymmetry threshold classification method may serve as a reference for performance evaluation in other sports.

Indexed as

drop jumplimb dominanceregression treespeed skatersquat jump

Identifiers

PMID41889795
PMCPMC13013065

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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.