The Relationship Between Functional Movement, Dynamic Stability, and Athletic Performance Assessments in Baseball and Softball Athletes.

ABSTRACT: Stapleton, DT, Boergers, RJ, Rodriguez, J, Green, G, Johnson, K, Williams, P, Leelum, N, Jackson, L, and Vallorosi, J. The relationship between functional movement, dynamic stability, and athletic performance assessments in baseball and softball athletes. J Strength Cond Res 35(12S): S42-S50, 2021-Despite recent popularity, the relationship between movement quality and measures of athletic performance remains inconclusive. This investigation sought to clarify the relationships between measures of movement quality and measures of athletic performance in baseball and softball athletes. Thirty-eight National Collegiate Athletic Association Division I baseball (n = 23; age 20.00 ± 1.38 years, lower-extremity [LE] limb length 93.91 ± 4.37, upper-extremity [UE] limb length 92.37 ± 4.48) and softball (n = 15; age 19.93 ± 1.28 years, LE limb length 89.43 ± 4.67, UE limb length 84.61 ± 4.39) athletes completed the Functional Movement Screen (FMS) and the Y Balance Test for the lower and upper extremities (YBTLQ and YBTUQ, respectively). Performance assessments were proagility (PA), vertical jump (VJ), and rotational medicine ball throw to the right and left (RMTR and RMTL, respectively). No significant correlations were seen between any of the composite scores of movement quality and athletic performance in baseball athletes; shoulder mobility was weakly correlated with PA (rs = 0.442, p = 0.035). Composite FMS was negatively correlated with RMTR (rs = -0.753) in softball athletes. In addition, in softball athletes, RMTR was negatively correlated with in-line lunge (rs = -0.544, p = 0.04), trunk stability push-up (rs = -0.761, p = 0.002), anterior YBTLQ reach (r = -0.628), and posterolateral YBTLQ reach (r = -0.683); VJ was correlated with posterolateral YBTLQ reach (r = 0.531) and superolateral (SL) YBTUQ reach (r = 0.591), and PA was negatively correlated with posterolateral YBTLQ (r = -0.60) and SL YBTUQ reach (r = -0.557). The differences in correlations of movement quality and athletic performance between baseball and softball athletes suggest movement quality influences performance differently in female athletes and male athletes.