Biomechanics Laboratory and the John Worley Sports Medicine Research Center, Utah State University, Logan, UT 84322, USA.
Med Sci Sports Exerc. 2011 Oct;43(10):1927-32. doi: 10.1249/MSS.0b013e318219dae7.
The study's purpose was to determine whether trunk muscle activity levels are different during spine stability exercises performed in water compared with on land.
Eleven male participants performed four abdominal trunk exercises on land and in water at the depth of the xiphoid. The exercises were abdominal hollowing, abdominal bracing, and anteroposterior and mediolateral pelvic tilts. During the exercises, surface EMG activity of muscles rectus abdominis (RA), external oblique, lower abdominals, multifidus, and erector spinae (ES) were recorded. EMG data were normalized to a maximal voluntary contraction (MVC), and the subsequent percentage of activity was compared between environments (water and land) with paired t-tests.
Normalized EMG values for muscles RA, external oblique, lower abdominals, multifidus, and ES were significantly greater for all exercises performed on land than in water (P = 0.026-0.001, effect sizes = 0.52-1.61). The only exception was for mediolateral pelvic tilts where muscle ES values were not different between environments (P = 0.098).
When healthy adults perform abdominal hollowing, abdominal bracing, and pelvic tilt exercises in water, most trunk muscles display substantially lower EMG activity when compared with performing the same exercises on land (e.g., abdominal bracing for RA = 20% MVC for land and 10% MVC for water). It is possible that with hydrostatic pressure and buoyancy, trunk muscles play less of a stabilizing role in the aquatic environment, which minimizes their EMG activity levels. Regardless of the mechanism, patients with back pain may find it easier to perform trunk muscle exercises in an aquatic environment first then progress to the land environment because EMG activity may be gradually increased.
本研究旨在确定在水中进行脊柱稳定性练习时，与在陆地上相比，躯干肌肉的活动水平是否存在差异。
11 名男性参与者在胸骨深度处的陆地上和水中进行了四项腹部躯干运动，包括腹部收紧、腹部支撑以及前后和左右骨盆倾斜。在运动过程中，记录了腹直肌（RA）、外斜肌、下腹肌、多裂肌和竖脊肌（ES）的表面肌电图（EMG）活动。将 EMG 数据归一化为最大自主收缩（MVC），并通过配对 t 检验比较环境（水和陆地）之间的活动百分比。
陆地进行所有运动时，RA、外斜肌、下腹肌、多裂肌和 ES 的肌肉 EMG 值归一化均显著大于水（P = 0.026-0.001，效应大小= 0.52-1.61）。唯一的例外是左右骨盆倾斜，其中 ES 肌肉的 EMG 值在两种环境之间没有差异（P = 0.098）。
当健康成年人在水中进行腹部收紧、腹部支撑和骨盆倾斜运动时，与在陆地上进行相同运动相比，大多数躯干肌肉的 EMG 活动明显较低（例如，陆地的 RA 腹部支撑为 20%MVC，而水中为 10%MVC）。可能是由于静水压力和浮力的作用，在水环境中，躯干肌肉在稳定方面的作用较小，从而使它们的 EMG 活动水平降低。无论机制如何，腰痛患者可能会发现，首先在水环境中进行躯干肌肉运动更容易，然后再进展到陆地环境，因为 EMG 活动可能会逐渐增加。
