Petrofsky Jerrold, Prowse Michelle, Bain Melanie, Ebilane Elaine, Suh Hye Jin, Batt Jennifer, Lawson Daryl, Hernandez Viviana, Abdo Armia, Yang Tien-Ning, Mendoza Enrique, Collins Kelly, Laymon Michael
Department of Physical Therapy, Loma Linda University, Loma Linda, CA 92350, USA.
Eur J Appl Physiol. 2008 Jun;103(3):265-73. doi: 10.1007/s00421-008-0700-3. Epub 2008 Feb 23.
Electrical stimulation is commonly used for strengthening muscle but little evidence exists as to the optimal electrode size, waveform, or frequency to apply. Three male and three female subjects (22-40 years old) were examined during electrical stimulation of the quadriceps muscle. Two self adhesive electrode sizes were examined, 2 cm x 2 cm and 2 cm x 4 cm. Electrical stimulation was applied with square and sine waveforms, currents of 5, 10 and 15 mA, and pulse widths of 100-500 micros above the quadriceps muscle. Frequencies of stimulation were 20, 30, and 50 Hz. Current on the skin above the quadriceps muscle was measured with surface electrodes at five positions and at three positions with needle electrodes in the same muscle. Altering pulse width in the range of 100-500 micros, the frequency over a range of 20-50 Hz, or current from 5 to 15 mA had no effect on current dispersion either in the skin or within muscle. In contrast, the distance separating the electrodes caused large changes in current dispersion on the skin or into muscle. The most significant finding in the present investigation was that, while on the surface of the skin current dispersion was not different between sine and square wave stimulation, significantly more current was transferred deep in the muscle with sine versus square wave stimulation. The use of sine wave stimulation with electrode separation distances of less then 15 cm is recommended for electrical stimulation with a sine wave to achieve deep muscle stimulation.
电刺激常用于增强肌肉力量，但关于最佳电极尺寸、波形或应用频率的证据很少。在对三名男性和三名女性受试者（22 - 40岁）的股四头肌进行电刺激时进行了检查。研究了两种自粘电极尺寸，2厘米×2厘米和2厘米×4厘米。在股四头肌上方施加方形和正弦波形的电刺激，电流分别为5、10和15毫安，脉冲宽度为100 - 500微秒。刺激频率为每秒20、30和50次。使用表面电极在五个位置以及在同一肌肉中的三个位置使用针电极测量股四头肌上方皮肤的电流。在100 - 500微秒范围内改变脉冲宽度、在20 - 50赫兹范围内改变频率或在5 - 15毫安范围内改变电流，对皮肤或肌肉内的电流分散均无影响。相比之下，电极之间的距离会导致皮肤或肌肉内电流分散的巨大变化。本研究中最显著的发现是，虽然在皮肤表面正弦波和方波刺激下的电流分散没有差异，但与方波刺激相比，正弦波刺激时更多的电流会深入肌肉。建议在进行正弦波电刺激以实现深层肌肉刺激时，使用电极间距小于15厘米的正弦波刺激。
