Work

Correlation of absolute and relative limb differences in Y-balance test and asymmetry indices of CMJ, SJ and IMTP

Year: 2025

Type: article

Abstract: Determine the relationship between Y-Balance Test (YBT) and force platform-based assessments, including squat jump (SJ), countermovement jump (CMJ), and isometric mid-thigh pull (IMTP), to evaluate lower limb stability and asymmetry. Sixty-one recruited active professional firefighters were assessed for YBT absolute limb differences (anterior, posteromedial, and posterolateral directions) using the YBT classic formula or a force platform built-in formula, and for asymmetry indices of CMJ, SJ and IMTP derived from the force platform. The absolute limb differences in YBT anterior (YBT-A) showed a moderate correlation (r > 0.4) with asymmetry indices of SJ concentric peak force (SJ-CPF), IMTP peak force component (IMTP-PFC), and IMTP peak force (IMTP-PF). Subsequently, limb relative differences for YBT-A were calculated using the built-in formula of the force platform, which also showed a moderate correlation (r > 0.4) with asymmetry indices of SJ-CPF, IMTP-PFC, and IMTP-PF. However, when considering either absolute or relative differences, YBT posteromedial asymmetry (YBT-PMA) or YBT posterolateral asymmetry (YBT-PLA) showed weak or negative correlations with asymmetry indices derived from the force platform. This study demonstrated that YBT anterior asymmetry (YBT-AA) calculated by using either the YBT classic formula or the built-in formula of the force platform, showed a moderate correlation with asymmetry indices derived from the force platform. This study provides clinicians and researchers with different test methods for assessing lower limb stability. • There is a certain correlation between YBT absolute/relative limb differences and asymmetry indices of SJ, CMJ, IMTP. • Moderate correlation (r > 0.4) between YBT anterior and SJ-CPF,IMTP-PF support different asymmetry evaluation. • YBT anterior consistently is applied in practice by whether classic YBT formula or force platform formula. • YBT may be a potential alternative method to force platform, and expand more formulas for lower limb asymmetry assessment.

Source: Musculoskeletal Science and Practice

DOI: 10.1016/j.msksp.2025.103320

Authors: Longji Li, Tianfei Fan, Kaifang Liao, Lifeng Zhang

Institutions: Chengdu Sport University, Sichuan University, West China Hospital of Sichuan University

Language: English

Topic: Occupational Health and Performance

Subfield: Occupational Therapy

Field: Health Professions

Domain: Health Sciences

SDG: Good health and well-being

Open Access status: hybrid

Estimated APC paid: $3,500