USE OF RUSSIAN AND AUSSIE CURRENT IN ISOMETRIC TETANIZATION OF THE QUADRICEPS FEMORIS

ABSTRACT Objectives: To qualitatively and quantitatively analyze the interaction of Russian and Aussie currents in isometric contraction of the quadriceps femoris muscle in the sensory, motor and pain tolerance spectra in healthy young women. Methods: The subjects were studied at a single point in time. A lower limb was selected at random to receive each current, and the electrodes were placed simultaneously on both legs, respecting 10 minutes between individual stimulation. Sensory, motor and pain-tolerance thresholds were assessed in quantitative (current density in mA/cm²) and qualitative (VAS) terms. Results: Subjects were 19 volunteers, aged 22.31 (1.29), with a BMI of 21.79 (1.78). The Aussie current reached the sensory threshold with significantly lower current density when compared with the Russian current for the same threshold. The results were significant in the overall group (treatment) for the two currents studied in terms of current density needed to reach the three thresholds. However, in the blocks (individually), there was significance only for the sensory threshold (p = 0.0126). Analysis of the perception of discomfort, assessed by VAS, was significant at the three time points for both currents, but in the comparison between these there was no significant difference. Conclusion: The Russian and Aussie currents are adequate in terms of the current density required to reach each threshold studied, and present differences between one another during interaction with the biological system, with the Aussie current necessitating less energy. However, in terms of perception of discomfort there are no significant differences between the two currents. Level of evidence III; Therapeutic studies - Investigating the results of treatment.

摘要
研究目的：对健康青年女性股四头肌等长收缩时，俄罗斯电流与澳大利亚电流在感觉、运动及痛觉耐受维度的交互作用进行定性与定量分析。
研究方法：本研究仅在单一时点对受试者开展检测。随机选取一侧下肢施加对应电流，电极同时置于双侧下肢，单次刺激之间需间隔10分钟。分别以定量（电流密度，单位：mA/cm²）与定性（视觉模拟评分法(VAS)）方式，评估感觉阈值、运动阈值及痛觉耐受阈值。
研究结果：本研究共纳入19名志愿者，年龄为22.31±1.29岁，体质量指数(BMI)为21.79±1.78。相较于达到相同阈值的俄罗斯电流，澳大利亚电流达到感觉阈值所需的电流密度显著更低。在整体受试干预组中，两种研究电流达到三类阈值所需的电流密度差异均具有统计学意义。但在亚组单独分析中，仅感觉阈值的差异具有统计学意义（p=0.0126）。通过VAS评估的不适感感知分析显示，两种电流在三个观测时间点的结果均具有统计学意义，但二者间比较无显著差异。
研究结论：俄罗斯电流与澳大利亚电流在达到本研究所涉及的各类阈值所需的电流密度方面均具备可行性，二者与生物系统交互时存在差异，其中澳大利亚电流所需能量更少。但在不适感感知层面，两种电流无显著差异。证据等级为Ⅲ级；治疗性研究——探讨治疗效果。