What is the influence of biomechanical variables on the Y balance test performance in recreational runners?

Background Asymmetries and poor Y balance test (YBT) performance are associated with an increased risk of injuries in athletes. The aim of this study was to investigate the association between YBT performance with biomechanical variables in runners. Methods The runners underwent the YBT, followed by the assessment of center of pressure, plank position, muscle strength (MS) of hip flexors, extensors, abductors, and external rotators, knee extensors, ankle dorsiflexion range of motion (ROM), Q angle, forefoot alignment, and passive hip internal rotation. Associations between variables were examined using multiple linear regression models with the Bayesian Information Criterion. Results 122 cases were analyzed. The R2 values were 0.38; 0.05; 0.06; and 0.15 for the anterior, posteromedial, posterolateral and composite directions models, respectively. The anterior reach in the YBT was associated with ankle dorsiflexion ROM [Sβ 95%IC: 0.43(0.32–0.55)], passive hip internal rotation [Sβ 95%IC: 0.35 (0.24–0.47)], MS of the hip extensors [Sβ 95%IC: 0.19(0.07–0.31)] and forefoot alignment [Sβ 95%IC: 0.14(-0.25-0.02)]. The posteromedial and posterolateral reach were associated with MS of the hip flexors [Sβ 95%IC: 0.23(0.09–0.37) and 0.24 (0.11–0.38)], respectively. The composite score was associated with MS of the hip flexors [Sβ 95%IC: 0.31(0.18–0.45)], ankle dorsiflexion ROM [Sβ 95%IC: 0.24(0.10–0.37)] and Q angle [Sβ 95%IC: 0.18(0.04–0.31)]. Conclusion YBT performance in different directions demonstrated specific associations with key biomechanical factors.