Colier W N, Meeuwsen I B, Degens H, Oeseburg B
Department of Physiology, Faculty of Medical Sciences, University of Nijmegen, The Netherlands.
Acta Anaesthesiol Scand Suppl. 1995;107:151-5. doi: 10.1111/j.1399-6576.1995.tb04350.x.
The aim of this study was to determine oxygen consumption (VO2) during isometric exercise in human muscles using near infrared spectroscopy (NIRS). The technique was used to study the relationship between VO2 in the soleus muscle and the level of isometric exercise expressed as percentages of the maximum voluntary contraction (MVC). For the study 11 healthy male volunteers were recruited. Reproducibility was studied in 6 subjects. The subjects were seated in a chair with the knee joint at an angle of 90 degrees. The optodes of the NIRS instrument were attached to the lateral aspect of the soleus muscle. A horizontal bar above the knee was connected to a dynamometer. Subjects applied isometric force to the bar by producing a torque at the ankle joint. Firstly the MVC was determined. Secondly the VO2 at rest and at 5 levels of isometric exercise, ranging from 5% to 25% of MVC and increasing by 5% each stage, was measured. In all cases the VO2 at rest or during isometric contraction was determined from the decrease of the oxyhaemoglobin (O2Hb) signal immediately after arterial occlusion of the thigh. Repeated measurements showed no significant difference between trials, indicating that the measurements were reproducible. At rest a VO2 of 6.7 +/- 1.1 microMO2Hb.min-1 (mean +/- S.E.M.) was found, a result comparable with other studies. In all subjects a linear relationship was found between the VO2 and the level of exercise. The average slope of the regression lines of all individuals was 0.85 +/- 0.22 microMO2Hb.min-1.%MVC-1 (mean +/- S.E.M.). Inter-individual variation of the slopes was high and ranged from 0.28 to 2.29 microMO.Hb.min-1.%MVC-1, which can be explained by differences in fat percentage and in the measuring volume of the NIRS instrument. NIRS appeared to be a reproducible and reliable method for the non-invasive measurement of VO2 in human muscles. The method could be used to investigate regional differences as well as changes in time between muscle groups as a function of training.
本研究的目的是使用近红外光谱技术（NIRS）测定人体肌肉等长运动期间的耗氧量（VO2）。该技术用于研究比目鱼肌的VO2与以最大自主收缩（MVC）百分比表示的等长运动水平之间的关系。为进行本研究，招募了11名健康男性志愿者。对6名受试者进行了重复性研究。受试者坐在椅子上，膝关节呈90度角。NIRS仪器的光极附着在比目鱼肌的外侧。膝盖上方的水平杆连接到测力计。受试者通过在踝关节处产生扭矩，对等长杆施加力。首先测定MVC。其次，测量静息状态下以及等长运动5个水平（范围为MVC的5%至25%，每个阶段增加5%）时的VO2。在所有情况下，静息状态或等长收缩期间的VO2是根据大腿动脉闭塞后立即出现的氧合血红蛋白（O2Hb）信号下降来确定的。重复测量显示各试验之间无显著差异，表明测量具有可重复性。静息时，VO2为6.7±1.1微摩尔O2Hb·min-1（平均值±标准误），该结果与其他研究相当。在所有受试者中，VO2与运动水平之间均发现存在线性关系。所有个体回归线的平均斜率为0.85±0.22微摩尔O2Hb·min-1·%MVC-1（平均值±标准误）。斜率的个体间差异很大，范围为0.28至2.29微摩尔O2Hb·min-1·%MVC-1，这可以用体脂百分比和NIRS仪器测量体积的差异来解释。NIRS似乎是一种用于无创测量人体肌肉VO2的可重复且可靠的方法。该方法可用于研究不同肌肉群之间的区域差异以及随训练时间的变化。
