Department of Physical Therapy, University of New England, Portland, Maine.
Department of Orthopaedic Surgery, Washington University School of Medicine, St. Louis, Missouri; and.
J Strength Cond Res. 2021 Feb 1;35(Suppl 1):S120-S126. doi: 10.1519/JSC.0000000000002788.
Lawrence, MA, Ostrowski, SJ, Leib, DJ, and Carlson, LA. Effect of unstable loads on stabilizing muscles and bar motion during the bench press. J Strength Cond Res 35(2S): S120-S126, 2021-Unstable loads are anecdotally used to increase muscle stabilizer strength and utilization; however, there is little evidence to support these claims. Twelve male powerlifters (age 28.6 ± 5.2 years, body mass 105.6 ± 14.5 kg, lifting experience 9.8 ± 6.0 years, and bench press 5 repetition maximum [5RM] 133.6 ± 30.9 kg) pressed their 5RM in one stable condition with a standard barbell, and 3 unstable conditions using a flexible barbell with weights suspended from elastic bands. Mean integrated muscle activity for each repetition of the stabilizers and prime movers were measured. A Lyapunov exponent and sample entropy indicated unstable loads were less predictable and more variable in the superior/inferior direction, thus more challenging to control, despite decreased loads. The main finding was increased bicep activity in all unstable conditions (light bands and plates, +57%; mini bands and plates, +67%; and mini bands and kettlebells, +88%). Although less weight was used in the unstable 5RMs, most stabilizer muscle activity was not different between conditions, suggesting that the amount of weight used during unstable load training (up to 32.3% less load) may be limited by the ability of stabilizer muscles to control the load.
劳伦斯，马萨诸塞州，奥斯特罗夫斯基，SJ，利伯，DJ 和卡尔森，LA。不稳定负荷对卧推过程中稳定肌和杠铃运动的影响。J 力量与体能研究 35（增刊 2）：S120-S126，2021 年——不稳定负荷被传闻用于增加肌肉稳定器的力量和利用率；然而，几乎没有证据支持这些说法。12 名男性力量举重运动员（年龄 28.6±5.2 岁，体重 105.6±14.5 公斤，举重经验 9.8±6.0 年，卧推 5 次重复最大重量 [5RM]133.6±30.9 公斤）在一种稳定条件下用标准杠铃进行了 5RM 测试，在 3 种不稳定条件下用带有弹性带悬挂重物的柔性杠铃进行了 5RM 测试。测量了每个稳定器和主驱动肌重复的平均综合肌肉活动。Lyapunov 指数和样本熵表明，尽管负荷减小，但不稳定负荷在上下方向上更不可预测且更具变异性，因此更难控制。主要发现是所有不稳定条件下的二头肌活动增加（轻带和板，+57%；小带和板，+67%；小带和壶铃，+88%）。尽管在不稳定的 5RM 中使用的重量较小，但大多数稳定肌的活动在不同条件之间没有差异，这表明在不稳定负荷训练中使用的重量量（最多减少 32.3%的负荷）可能受到稳定肌控制负荷的能力的限制。
