Zhang J, Clement D, Taunton J
Allan McGavin Sports Medicine Centre, School of Human Kinetics, University of British Columbia, Vancouver, Canada.
Clin J Sport Med. 2000 Jan;10(1):15-21. doi: 10.1097/00042752-200001000-00004.
To assess the hypothesis that Farabloc, a fabric with electromagnetic shielding properties, would attenuate the symptoms, signs, and muscular strength deficit secondary to delayed-onset muscle soreness (DOMS) induced by two exposures to eccentric exercise in humans.
Randomized, single-blind, placebo-controlled, crossover trial with two testing stages of 5 days duration separated by a washout period of more than 8 weeks.
University-based sports medicine center.
Twenty volunteers equally representing untrained male and female subjects.
20 sets of 10 repetitions of single-leg eccentric knee extensions for 37 minutes with the Biodex dynamometer set at 30 degrees per second were performed on the first day of stage one and stage two to induce DOMS in the quadriceps muscle. Double layers of fabric, either Farabloc or placebo, were wrapped around the thigh of each participant during each stage for 5 days.
Perception of muscle pain, as measured by a visual analog scale (VAS), and strength, as measured by knee extensor torque (EST) with the Biodex dynamometer, were evaluated at 0, 24, 48, 72, and 96 hours. Serum inflammatory markers of muscle damage, including malondialdehyde. creatine phosphokinase, myoglobin, leukocytes, and neutrophils, were assayed at 0, 2, 6, 24, and 48 hours.
Repeated-measures analysis of variance was carried out for each of the seven variables to assess differences for fabric, order of treatment, time, and all combinations. Results of VAS and EST and levels of malondialdehyde, creatine phosphokinase, myoglobin, leukocytes, and neutrophils all showed a highly significant effect of Farabloc compared with placebo. This analysis shows that the order of Farabloc or placebo fabric use in stage I and 2 produces different results. This may be caused by a learning effect, but did not alter the overall influence of Farabloc.
The data indicate that double layers of Farabloc fabric wrapped around the thigh reduces pain and strength loss and serum levels of malondialdehyde, creatine phosphokinase, myoglobin, leukocytes, and neutrophils when untrained human subjects are exposed to eccentric exercise to produce DOMS in the quadriceps. Farabloc shields high-frequency electromagnetic fields, although the results do not indicate how these changes are mediated. Further research is needed to determine the mechanism.
评估具有电磁屏蔽特性的织物Farabloc能否减轻人体因两次离心运动诱发延迟性肌肉酸痛（DOMS）继发的症状、体征及肌肉力量 deficit。
随机、单盲、安慰剂对照、交叉试验，有两个为期5天的测试阶段，中间间隔超过8周的洗脱期。
大学体育医学中心。
20名志愿者，男女比例均等，均为未经训练的受试者。
在第一阶段和第二阶段的第一天，使用Biodex测力计以每秒30度的速度进行20组单腿离心膝关节伸展，每组10次，持续37分钟，以诱发股四头肌的DOMS。在每个阶段，为每位参与者的大腿包裹双层织物，为期5天，织物为Farabloc或安慰剂。
在0、24、48、72和96小时时，通过视觉模拟量表（VAS）测量肌肉疼痛感知，并使用Biodex测力计测量膝关节伸展扭矩（EST）以评估力量。在0、2、6、24和48小时时，检测肌肉损伤的血清炎症标志物，包括丙二醛、肌酸磷酸激酶、肌红蛋白、白细胞和中性粒细胞。
对七个变量中的每一个进行重复测量方差分析，以评估织物、治疗顺序、时间以及所有组合之间的差异。与安慰剂相比，VAS、EST以及丙二醛、肌酸磷酸激酶、肌红蛋白、白细胞和中性粒细胞水平的结果均显示Farabloc具有高度显著的效果。该分析表明，第一阶段和第二阶段使用Farabloc或安慰剂织物的顺序会产生不同结果。这可能是由学习效应引起的，但并未改变Farabloc的总体影响。
数据表明，当未经训练的人体受试者进行离心运动以诱发股四头肌的DOMS时，包裹在大腿周围的双层Farabloc织物可减轻疼痛和力量损失，并降低丙二醛、肌酸磷酸激酶、肌红蛋白、白细胞和中性粒细胞的血清水平。Farabloc可屏蔽高频电磁场，尽管结果未表明这些变化是如何介导的。需要进一步研究以确定其机制。
