Evidence map›Paper›PMID 42157231›Full record

ArticleBMC sports science, medicine & rehabilitation2026

Load-velocity relationship during chain-based variable resistance in the smith machine back squat.

Zhuorong Huang, Jie Li, Zhaoqian Li, Xing Zhang, Ruizhi Liu, Zongwei Chen, Xiuli Zhang, Amador García-Ramos

Abstract read
In one paragraph

Article in BMC sports science, medicine & rehabilitation, 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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1 · What the graph read from it

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3 · Its place in the literature

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4 · The record

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5 · Who and what money

Authors and funding

8 authors.

Zhuorong HuangSchool of Physical Education and Sports Science, South China Normal University, Guangzhou, China.
Jie LiSchool of Sports Training, Tianjin University of Sport, Tianjin, China.
Zhaoqian LiSchool of Physical Education, Shandong University, Jinan, China.
Xing ZhangDepartment of Physical Education and Sport, Faculty of Sport Sciences, University of Granada, Granada, Spain.
Ruizhi LiuSchool of Physical Education and Sports Science, South China Normal University, Guangzhou, China. scnuray@126.com.
Zongwei ChenSchool of Physical Education and Sports Science, South China Normal University, Guangzhou, China. zongwei@correo.ugr.es.
Xiuli ZhangSchool of Physical Education and Sports Science, South China Normal University, Guangzhou, China. hzhzhz411@126.com.
Amador García-RamosDepartment of Physical Education and Sport, Faculty of Sport Sciences, University of Granada, Granada, Spain.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

backgroundVelocity-based training (VBT) is well established for prescribing and monitoring intensity in traditional constant resistance training; however, its applicability to chain-based variable resistance training has not been examined. This study examined how different magnitudes of chain-based variable resistance influence commonly used VBT-derived metrics.

methodsThirty-four resistance-trained men (age: 20.50 ± 2.00 years, constant-load one-repetition maximum [1RM]: 1.85 ± 0.22 × body mass) performed Smith machine back squats under three loading configurations (0%, 20%, and 60% of the total external load supported by chains). Across six sessions (two per configuration), participants' mean concentric velocity (MV) was assessed at 45%, 60%, 75%, and 90% of their constant-load 1RM. In three additional sessions (one per configuration), a subset of 21 men (age: 20.29 ± 1.76 years, constant-load 1RM: 1.91 ± 0.19 × body mass) performed four sets to failure at 70% of constant-load 1RM.

resultsThe individual load-MV relationships were highly linear across the three configurations (R

conclusionsAllocating a greater proportion of the load to chains enhances movement velocity at heavy loads and consequently increases the predicted 1RM during the Smith machine back squat. The preserved linearity of the load-MV relationship supports the use of VBT for prescribing and monitoring intensity under variable resistance training; however, the %1RM-MV relationship is configuration-specific and therefore requires tailored calibration according to the proportion of chain load used. Given the growing popularity of combining variable resistance with VBT, the importance of this study lies in providing the first empirical framework for prescribing and monitoring chain-based training intensity using individual %1RM-MV relationships.

Indexed as

KinematicMonitoringTraining intensityVelocity-based training

Identifiers

PMID42157231
PMCPMC13359936

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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.