Development and Validation of The Iliopsoas Endurance Test: A Reliable Tool for Clinical and Functional Assessment

Year 2026, Volume: 10 Issue: 1, 122 - 129, 31.01.2026

Emre Şenocak , Seda Karaca , Zubeyir Sarı , Aysel Yıldız Özer

https://doi.org/10.30621/jbachs.1659864

Abstract

Development and Validation of The Iliopsoas Endurance Test: A Reliable Tool for Clinical and Functional Assessment

Abstract

Purpose: The iliopsoas muscle complex is vital for lumbar stabilization, posture, and hip flexion, yet its endurance is often overlooked in clinical and research settings. This study aimed to develop and validate the Iliopsoas Endurance Test (IET), a cost-effective and practical method for assessing iliopsoas endurance.
Methods: Healthy participants aged 18–38 years were evaluated. The IET involved performing hip flexion-extension movements within an 80-degree range while supine, and measurements were taken over 60 seconds. Reliability was assessed using intraclass correlation coefficients (ICC) for inter- and intra-rater agreements, while the validity of the IET was determined by its correlation with isokinetic assessments.
Results: The IET demonstrated excellent intra-rater (ICC=0.802) and good inter-rater (ICC=0.701) reliability. Strong correlations were observed between IET repetitions and isokinetic dynamometer measurements for peak torque (r=0.706, p<0.001) and total repetitions (r=0.629, p<0.001). The findings support the IET as a reliable alternative to isokinetic testing, particularly in settings where access to specialized equipment is limited.
Conclusions: The IET is a practical, reliable, and cost-effective tool for assessing iliopsoas endurance, with potential applications in clinical diagnostics, rehabilitation, and performance analysis. Future research should explore its applicability across diverse populations and its role in long-term rehabilitation outcomes.

Keywords

Ilıopsoas , hip flexion , endurance , isokinetic dynamometer

Ethical Statement

This methodological study was approved by the Marmara University Faculty of Medicine Clinical Research Ethics Committee (ID: 09.2022.650).

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