Force plate-based isometric assessments are widely used to evaluate force-time characteristics in athletes, offering a safe and reliable measure of maximal force production. The isometric mid-thigh pull is the most established test, demonstrating excellent reliability and associations with key athletic qualities, although its bilateral design may not reflect the unilateral demands of many sports. The recently developed run-specific knee isometric push (RSKIP) provides a unilateral alternative that may better replicate sport-specific actions and support rehabilitation monitoring. However, its measurement reliability remains unknown. Therefore, this study aimed to evaluate the test-retest, intra-rater, and inter-rater reliability of the RSKIP protocol in adolescent athletes.