Exercise Nutrition Research Laboratory, School of Kinesiology, Faculty of Health Sciences, The University of Western Ontario, London, Ontario, Canada.
J Strength Cond Res. 2010 Jul;24(7):1860-5. doi: 10.1519/JSC.0b013e3181ddf6c8.
The purpose of this investigation was to examine if the addition of a light external load would enhance whole-body vibration (WBV)-induced increases in muscle activity during dynamic squatting in 4 leg muscles. Thirteen recreationally active male university students performed a series of dynamic squats (unloaded with no WBV, unloaded with WBV, loaded with no WBV, and loaded with WBV). The load was set to 30% of body mass and WBV included 25-, 35-, and 45-Hz frequencies with 4-mm amplitude. Muscle activity was recorded with surface electromyography (EMG) on the vastus lateralis (VL), biceps femoris (BF), tibialis anterior (TA), and gastrocnemius (GC) and is reported as EMGrms (root mean square) normalized to %maximal voluntary exertion. During unloaded dynamic squats, exposure to WBV (45 Hz) significantly (p < 0.05) increased baseline muscle activity in all muscles, except the TA compared with no WBV. Adding a light external load without WBV increased baseline muscle activity of the squat exercise in all muscles but decreased the TA. This loaded level of muscle activity was further increased with WBV (45 Hz) in all muscles. The WBV-induced increases in muscle activity in the loaded condition (approximately 3.5%) were of a similar magnitude to the WBV-induced increases during the unloaded condition (approximately 2.5%) demonstrating the addition of WBV to unloaded or loaded dynamic squatting results in an increase in muscle activity. These results demonstrate the potential effectiveness of using external loads with exposure to WBV.
本研究旨在探讨在 4 块腿部肌肉进行动力深蹲时，外加轻负荷是否会增强全身振动（WBV）引起的肌肉活动增加。13 名有休闲运动习惯的男性大学生进行了一系列动力深蹲（无负荷、无 WBV 负荷、无 WBV 负荷和 WBV 负荷）。负荷设定为体重的 30%，WBV 包括 25、35 和 45Hz 频率和 4mm 振幅。使用表面肌电图（EMG）在股外侧肌（VL）、股二头肌（BF）、胫骨前肌（TA）和腓肠肌（GC）上记录肌肉活动，并以 EMGrms（均方根）表示，归一化为%最大自主用力。在无负荷动力深蹲时，暴露于 WBV（45Hz）会显著（p<0.05）增加所有肌肉的基线肌肉活动，除了 TA 与无 WBV 相比。在没有 WBV 的情况下，外加轻负荷会增加所有肌肉的深蹲运动基线肌肉活动，但会降低 TA。在所有肌肉中，这种加载水平的肌肉活动在有 WBV（45Hz）的情况下进一步增加。在加载条件下（约 3.5%），WBV 引起的肌肉活动增加与无负荷条件下（约 2.5%）相似，这表明在无负荷或加载动力深蹲时外加 WBV 会导致肌肉活动增加。这些结果表明，在使用外部负荷结合 WBV 暴露时，具有潜在的有效性。
