Purpose: To examine the test re-test reliability of isometric maximal voluntary contractions (MVC) of hip adduction (ADDISO), hip abduction (ABDISO), and multijoint leg extension (SQUATISO) in sub-elite female Australian footballers.
Methods: Data were collected from 24 sub-elite female Australian footballers (age: 22.6±4.5 y; height: 169.4±5.5 cm; body mass: 66.6±8.0 kg; 4.5±4.4 y sport-specific training; 2.5±2.0 y unstructured resistance training) from the same club on two non-consecutive days. Participants performed 3 isometric MVCs of ADDISO, ABDISO and SQUATISO. The SQUATISO was performed at 140° knee flexion with a vertical trunk position and ADDISO and ABDISO measures were performed in a supine position at 60° of knee flexion and 60° hip flexion. Reliability was assessed using paired T-tests and the intraclass correlation coefficient (ICC) with 95% confidence intervals (CI), typical error (TE) and coefficient of variation (CV%) with 95% CI.
Results: SQUATISO peak force (ICC: .95; CV%: 4.1), ABDISO for left, right and sum (ICC: .90 – .92; CV%: 5.0 – 5.7), and ADDISO for left, right and sum (ICC: .86 - .91; CV%: 6.2 – 6.9) were deemed acceptably reliable based on predetermined criteria (ICC ≥ .8 and CV% ≤ 10).
Conclusion: SQUATISO, ABDISO and ADDISO tests demonstrated acceptable reliability for the assessment of peak force in sub-elite female Australian footballers, suggesting these assessments are suitable for muscle strength testing and monitoring adaptations to training.