McCully Kevin K, Moraes Caio, Patel Sahil V, Green Max, Willingham T Bradley
Department of Kinesiology, University of Georgia, Athens, GA 30602, USA.
AU-UGA Medical Partnership, Athens, GA 30606, USA.
J Funct Morphol Kinesiol. 2019 Jan 27;4(1):12. doi: 10.3390/jfmk4010012.
Lower back pain is a common symptom potentially associated with skeletal muscle dysfunction. The purpose of this study was to evaluate endurance in the lower back muscles of healthy participants using accelerometer-based mechanomyography. Methods: Young healthy subjects (N = 7) were tested. Surface electrodes and a tri-axial accelerometer were placed over the erector spinae muscle along the T11-L1 Vertebrae. Stimulation was for 3 min each at 2, 4, and 6 Hz, and changes in acceleration were used to calculate an endurance index (EI). Reproducibility of the endurance index measurements was tested on two separate days. Wrist flexor and vastus lateralis muscles were tested for comparison. Near Infrared Spectroscopy (NIRS) was used to measure muscle oxygen levels (OHb) (N = 5). EI was 70.3 + 13.4, 32.6 + 8.4, and 19.2 + 6.2% for 2, 4, 6 Hz, respectively. The coefficients of variation were 9.8, 13.9, and 20.3% for 2, 4, 6 Hz, respectively. EI values were lower in the erector spinae muscles compared to the arm and the leg ( < 0.05). OHb values were 86.4 + 10.9% at rest and were 77.2 + 15.5, 84.3 + 14.1, and 84.1 + 18.9% for 2, 4, 6 Hz, respectively ( > 0.05, all comparisons). An endurance index can be obtained from the lower back erectors muscles that is reproducible and not influenced by voluntary effort or muscle oxygen levels.
下背部疼痛是一种可能与骨骼肌功能障碍相关的常见症状。本研究的目的是使用基于加速度计的肌动电流图评估健康参与者下背部肌肉的耐力。方法：对年轻健康受试者（N = 7）进行测试。将表面电极和三轴加速度计放置在沿T11 - L1椎骨的竖脊肌上。分别以2、4和6 Hz的频率刺激3分钟，并使用加速度变化来计算耐力指数（EI）。在两个不同的日子测试耐力指数测量的可重复性。测试腕屈肌和股外侧肌以作比较。使用近红外光谱（NIRS）测量肌肉氧含量（OHb）（N = 5）。2、4、6 Hz时的EI分别为70.3 + 13.4、32.6 + 8.4和19.2 + 6.2%。2、4、6 Hz时的变异系数分别为9.8、13.9和20.3%。与手臂和腿部相比，竖脊肌的EI值较低（<0.05）。静息时OHb值为86.4 + 10.9%，2、4、6 Hz时分别为77.2 + 15.5、84.3 + 14.1和84.1 + 18.9%（所有比较均>0.05）。可以从下背部竖脊肌获得一个可重复且不受自主努力或肌肉氧含量影响的耐力指数。
