Wahl Michael J, Behm David G
School of Human Kinetics and Recreation, Memorial University of Newfoundland, St. John's, Newfoundland, Canada.
J Strength Cond Res. 2008 Jul;22(4):1360-70. doi: 10.1519/JSC.0b013e318175ca3c.
The objective of this study was to measure the electromyographic (EMG) activity of the soleus, bicep femoris, rectus femoris, lower abdominal, and lumbosacral erector spinae (LSES) muscles with a variety of (a) instability devices, (b) stable and unstable (Dyna Disc) exercises, and (c) a fatiguing exercise in 16 highly conditioned individuals. The device protocol had participants assume standing and squatting postures while balancing on a variety of unstable platforms (Dyna Disc, BOSU ball, wobble board, and a Swiss ball) and a stable floor. The exercise protocol had subjects performing, static front lunges, static side lunges, 1-leg hip extensions, 1-leg reaches, and calf raises on a floor or an unstable Dyna Disc. For the fatigue experiment, a wall sit position was undertaken under stable and unstable (BOSU ball) conditions. Results for the device experiment demonstrated increased activity for all muscles when standing on a Swiss ball and all muscles other than the rectus femoris when standing on a wobble board. Only lower abdominals and soleus EMG activity increased while squatting on a Swiss ball and wobble board. Devices such as the Dyna Disc and BOSU ball did not exhibit significant differences in muscle activation under any conditions, except the LSES in the standing Dyna Disc conditions. During the exercise protocol, there were no significant changes in muscle activity between stable and unstable (Dyna Disc) conditions. With the fatigue protocol, soleus EMG activity was 51% greater with a stable base. These results indicate that the use of moderately unstable training devices (i.e., Dyna Disc, BOSU ball) did not provide sufficient challenges to the neuromuscular system in highly resistance-trained individuals. Since highly trained individuals may already possess enhanced stability from the use of dynamic free weights, a greater degree of instability may be necessary.
本研究的目的是测量16名训练有素的个体在使用各种（a）不稳定装置、（b）稳定和不稳定（动态圆盘）练习以及（c）疲劳练习时，比目鱼肌、股二头肌、股直肌、下腹部和腰骶竖脊肌（LSES）的肌电图（EMG）活动。装置方案让参与者在各种不稳定平台（动态圆盘、BOSU球、摇摆板和瑞士球）以及稳定地面上保持站立和蹲姿。练习方案让受试者在地面或不稳定的动态圆盘上进行静态前弓步、静态侧弓步、单腿髋伸展、单腿伸展和小腿抬高。对于疲劳实验，在稳定和不稳定（BOSU球）条件下进行靠墙静蹲姿势。装置实验结果表明，站在瑞士球上时所有肌肉的活动增加，站在摇摆板上时除股直肌外所有肌肉的活动增加。只有在下腹部和比目鱼肌在瑞士球和摇摆板上蹲姿时EMG活动增加。动态圆盘和BOSU球等装置在任何条件下肌肉激活均无显著差异，除了在站立动态圆盘条件下的LSES。在练习方案中，稳定和不稳定（动态圆盘）条件下肌肉活动无显著变化。在疲劳方案中，稳定支撑时比目鱼肌EMG活动高出51%。这些结果表明，在训练有素的个体中，使用适度不稳定的训练装置（即动态圆盘、BOSU球）对神经肌肉系统没有提供足够的挑战。由于训练有素的个体可能已经通过使用动态自由重量获得了增强的稳定性，可能需要更大程度的不稳定性。
