The impact of whole-body vibration training on adolescent baseball batting performance.

Introduction: Baseball batting is a high-speed, multi-joint coordinated movement that relies on the effective operation of the kinetic chain. Whole-body vibration (WBV) training has been proven to acutely enhance lower-limb muscle strength, but its effects on the batting kinematics of adolescent baseball players remain unclear. This study aimed to investigate the acute effects of WBV training, with and without added load, on the batting kinematics of adolescent baseball players. Methods: Thirty-two national adolescent baseball players were recruited and randomly divided into four groups: a non-vibration group, a whole-body vibration group, a 30% 1RM WBV group, and a 50% 1RM WBV group. All four groups performed the training in a semi-squat calf-raise posture for 60 s. Immediately after the intervention, participants performed maximal-effort swings, which were analyzed using the Kwon3D motion capture system. Results: When comparing the four conditions, both the non-loaded WBV and loaded WBV groups exhibited higher lower-limb and bat head speeds, with overall performance superior to the non-vibration group. The 50% 1RM group showed the highest knee joint angular velocity, while the 30% 1RM group was most prominent in rotation-related indicators for the thigh and pelvis segments. The non-loaded WBV group showed the highest elbow joint angular velocity. At the moment of bat-ball contact (mid-batting instant), the pelvic linear velocity in the WBV and 30% 1RM groups was significantly greater than that in the non-vibration group. Conclusion: All WBV training protocols acutely optimized key segments of the kinetic chain in the batting swing of adolescent baseball players. This offers a time-efficient training strategy and can serve as a practical reference for pre-training or pre-competition preparation.