Author Identifier (ORCID)
Paul Comfort: https://orcid.org/0000-0002-1131-8626
Abstract
The purpose of this study was to assess the between-session reliability of peak force and early force-time variables in a unilateral isometric hamstring assessment (isometric long-lever bridge). The sample consisted of 30 collegiate male athletes (age: 19.4±1.3 years; height: 1.79±0.1 m; body mass: 80.4±10.3 kg) with no history of recent hamstring injury (<6 months) who volunteered to participate in the study. All participants performed 3 unilateral maximal voluntary isometric contractions (MVIC) with their heels on force plates and shoulders elevated 15.24 cm, while their hips were secured with a loaded barbell. Data was analyzed to assess the reliability of force values at 50, 100, 150, 200, 250 ms, and peak force (N) across three repeated sessions. Moderate-good relative and absolute reliabilities were observed across all early force-time variables with lower bound ICC values≥0.51 (0.51–0.71) and point estimate CV%≤12.65% (7.63–12.65), with moderate relative (ICC≥0.74; range 0.74–0.92) and absolute (CV%≤6.50%; range 6.48–6.50) reliability for peak force. Trivial to small effect sizes (g≤0.4) were observed between sessions. These findings suggest that the isometric single-leg long-lever bridge (SL-LLB) can be used to reliably monitor peak and rapid force generating capacities to track performance changes over time due to training adaptations as well as acute or chronic fatigue.
Keywords
isometric strength, hamstring assessment, force-time characteristics, reliability analysis, athletic performance, muscle fatigue
Document Type
Journal Article
Date of Publication
5-1-2026
Volume
21
Issue
5 May
Publication Title
PLoS One
Publisher
PLOS
School
School of Medical and Health Sciences
Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 License.
Comments
Sundh, A. E., Ripley, N. J., Lamb, A., Cantwell, C. J., & Comfort, P. (2026). Between-session reliability and sensitivity of force production characteristics across various force-time points during the isometric single-leg long-lever bridge. PLoS One, 21(5), e0350197. https://doi.org/10.1371/journal.pone.0350197