Interlimb asymmetries have been recently investigated in athletic populations. However, the effects of training interventions on interlimb asymmetries have been scarcely examined. Therefore, the aim of this study was to determine the effects of training interventions on changes in interlimb asymmetries from pre- to post-training. Furthermore, to examine the effects of training programs on intervention groups compared with control groups. A database search was completed (MEDLINE, CINAHL, and SPORTDiscus). Eight studies were then included in the meta-analysis. Results showed small reductions in interlimb asymmetries in single-leg broad jump (SLBJ) and change of direction (COD) speed from pre- to post-training interventions, whereas moderate effects were found in single-leg countermovement jump (SLCMJ) and SL lateral jump. When comparing the training interventions with the control groups, results showed small effects in favor of the training groups for reducing interlimb asymmetries in SLBJ and large effects in SLCMJ and COD speed. Thus, training interventions can evoke small to moderate reductions in interlimb asymmetries from pre- to post-training programs. Strength training performed unilaterally or bilaterally may elicit these reductions. Furthermore, training interventions showed larger effects compared with the control groups in reducing interlimb asymmetries. However, further research is needed.

Multidirectional ground reaction forces (GRFs) and jump tests within baseball pitchers provide insight into athletic ability and coordination to produce lower-body force and power. Lower-body power is a biomechanical feature that denotes physiological capacity through dynamic and passive tissue stretch-shortening in transferring energy from the ground through the kinetic chain. Optimized lower-body power may lessen the magnitude of forces on the upper extremity. Insufficient lower-body power may create a greater risk of upper-body injury. Lower-body power and its relationship to ball velocity have been minimally investigated, yet some research points to a correlation between jumping ability and fastball velocity. Because pitching is unilateral, practitioners should consider unilateral jumps to determine the extent of bilateral asymmetry or stride to drive leg differences that can guide training to remediate deficiencies. The purposes of this brief review are to (a) examine factors that influence vertical jump performance among baseball players, (b) examine research on pitching multidirectional GRFs, and (c) examine literature concerning jump performances to baseball pitching performance. Collectively, this review can assist coaches and practitioners in lower-body power testing and training for baseball pitchers.

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The College Strength and Conditioning Coach of the Year Award is given to an outstanding Certified Strength and Conditioning Specialist® (CSCS) to recognize their dedication to improving athletic performance with safe and effective science-based programs.

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The U.S. Department of Health and Human Services (HHS) recently recognized the National Strength and Conditioning Association (NSCA) as one of the first organizations to join the National Youth Sports Strategy (NYSS) Champion℠ program. HHS released the NYSS in September 2019 in response to Presidential Executive Order 13824, which called for a national strategy to increase youth sports participation. The NYSS is the first Federal roadmap with actionable strategies to increase participation in youth sports, increase awareness of the benefits of youth sports participation, monitor and evaluate youth sports participation, and recruit and engage volunteers in youth sports programming.

Colorado Springs, CO - The National Strength and Conditioning Association (NSCA) is honored to announce the celebration of the 25th anniversary of NSCA Japan, the NSCA’s longest tenured affiliate partner.