How Many Familiarization Sessions Does the Isometric Squat Test Require for Stable Results

Kite, RJ and Callaway, A. How many familiarization sessions does the isometric squat test require for stable results? J Strength Cond Res 40(1): e104-e107, 2026-Isometric strength testing plays a key role in the assessment of athlete performance, with the isometric squat test (ISQT) providing a safe and efficient method to assess force production capacity. However, the optimal number of familiarization sessions remains limited and inconclusive within the current literature. Therefore, the aim of this study was to explore the quantity of sessions required to familiarize and stabilize performance of the ISQT. Fifteen male subjects of a mixed sporting background volunteered to participate in the study. Each subject underwent 4 days of testing separated by at least 24 hours. Each session consisted of 3 maximal ISQTs. Absolute and relative peak force data were captured using a force platform and a custom isometric rig. To examine the effects of sessions and trials, a generalized linear mixed model with a Gamma distribution and log-link function was applied, modeling subjects as random effects. To further assess the variability in performance, intraclass correlation coefficients (ICC) and coefficient of variation were calculated. The model identified significant effects (p < 0.05) within and between sessions, accompanied by a progressive reduction in variability over time, as indicated by increasing ICC (ICC = 0.905 for sessions 1 to 4; 0.949 for sessions 3 to 4). Overall, these outcomes support a minimum requirement for 3 familiarization sessions, with 3 trials per session, to ensure reliable ISQT performance outcomes. This study contributes to the standardization of isometric strength testing protocols and highlights the importance of adequate familiarization to mitigate within-subject variability.