Effects of a 4-Week Neuromuscular Training Program on Movement Competency During the Back-Squat Assessment in Pre- and Post-Peak Height Velocity Male Athletes

The back-squat assessment (BSA) is a novel movement screen to detect functional deficits; however, its sensitivity to detect meaningful changes in movement competency after exposure to short-term neuromuscular training remains unclear. Twenty-six pre- and 22 post-peak height velocity (PHV) males were divided into experimental (EXP) and control groups (CON) and performed the BSA before and after a twice weekly, 4-week neuromuscular training intervention. Intra-rater reliability was determined by rating both EXP group's baseline BSA on 3 separate sessions. Intraclass correlation coefficient (ICC) revealed very strong agreement for BSA total score in pre-PHV (ICC ≥ 0.81) and post-PHV (ICC ≥ 0.97) groups across all sessions, but systematic bias was evident in the pre-PHV group for sessions 1-2. Analysis of kappa values for BSA individual criteria showed greater variability for pre-PHV (K ≥ 0.31) than post-PHV (K ≥ 0.62) across sessions. At baseline, there were no differences in total score between the EXP and CON cohorts (p > 0.05). There were significant within-group improvements in total score for the EXP pre-PHV (5.0 to 3.0, effect size [ES] = 0.68) and post-PHV (2.0 to 1.0, ES = 0.82) cohorts, with no changes in total score for either CON groups (p > 0.05). Hip position was the criterion with the greatest improvement for both the EXP pre-PHV (12.0 to 7.0) and post-PHV (7.0 to 0.0) groups. The BSA seems to be a reliable screening tool for measuring movement competency in youth male athletes and was sensitive to adaptations in movement competency after neuromuscular training.