Effect of 6-week single leg countermovement jump training on force time metrics in elite female youth footballers.

Fahey, Jack T; Comfort, Paul; Jones, Paul; Ripley, Nicholas, J; Ripley, Nicholas J

Abstract

Female football participation has grown exponentially. Unfortunately, females exhibit greater injury risk than male athletes, and experience increased mechanical stress during adolescence. Force plates provide accurate and reliable force-time characteristics enabling profiling of injury risk and benchmarking using a variety of jump and isometric tasks. The purpose of this study was to determine whether test-retest reliability and force-time characteristics of SLCMJ, bilateral countermovement jump (CMJ), countermovement rebound jump (CMJ-R) and isometric mid-thigh pull (IMTP) change with six weeks of SLCMJ training. Twenty-eight elite youth female footballers (13.7 ± 1.1 years, 53.27 ± 8.82 kg, 162.20 ± 5.37 cm) completed six weeks of SLCMJ as part of a routine strength and plyometric training program. SLCMJ training did not influence test-retest reliability and resulted in favourable adaptations indicated through small to large changes in force-time characteristics for SLCMJ. Significant (  < 0.05) yet trivial to small favourable changes were observed for the CMJ and CMJ-R, with small increases observed for IMTP. The results of this study demonstrate that six weeks of SLCMJ training does not influence phase-specific test-rest reliability (i.e. braking and propulsion) and causes weekly fluctuations in force-time characteristics leading to improvements in SLCMJ, CMJ, CMJ-R and IMTP. Practitioners can use such information to inform training design and monitor athlete performance.

• Journal Article Type: Article
• Acceptance Date: Apr 18, 2025
• Online Publication Date: Apr 18, 2025
• Deposit Date: May 9, 2025
• Publicly Available Date: May 9, 2025
• Journal: Journal of sports sciences
• Print ISSN: 1466-447X
• Publisher: Taylor and Francis
• Peer Reviewed: Peer Reviewed
• DOI: https://doi.org/10.1080/02640414.2025.2489892
• Keywords: girls’ soccer, vertical jump, force plates, Unilateral, adolescent