Baker J, Gal J, Davies B, Bailey D, Morgan R
School of Applied Sciences, University of Glamorgan, Pontypridd, Wales.
J Sci Med Sport. 2001 Mar;4(1):10-8. doi: 10.1016/s1440-2440(01)80003-7.
Traditionally, leg cycle ergometry is used to assess the power output of the lower limbs. However, it is suspected that the upper body makes a significant, albeit as yet unknown, contribution to the measured power output, and as such, the lean mass of the whole body should be considered during ergometric assessment. To test this idea, indices of mechanical power output were obtained from 11 subjects during high intensity leg cycle ergometry tests (20 second duration; 75 grams per kilogram total body mass) using two protocols: one with a standard handle-bar grip (with grip) and one with supinated wrists (without-grip). Peak mechanical power, mean mechanical power, fatigue index and total mechanical work values were calculated for each subject during each test and the sample mean differences associated with the two protocols were compared using paired Student t-tests. The with-grip protocol yielded significantly greater peak mechanical power output than the without-grip protocol (886+/-124 W and 815+/-151 W, respectively), suggesting a significant upper body contribution to the maximum power output measured for the legs. As a first step towards quantifying the upper body involvement during leg cycle ergometry, surface electromyography of the forearm musculature was measured in a twelfth subject whilst performing each of the test protocols. During the with-grip ergometer tests, the intensity of electrical activity in the forearm musculature was similar, if not greater than, the intensity of electrical activity recorded for the forearm musculature during 100% maximum voluntary hand grip-dynamometer contractions, suggesting maximum isometric-type forearm muscle contraction during the with-grip leg ergometry tests. These findings suggest that the performance of traditional-style leg cycle ergometry requires a muscular contribution from the whole body. As such, researchers should be mindful of this, both in terms of the allocation of ergometer loads, and in the analysis of blood-borne metabolites.
传统上，腿部蹬车测力法用于评估下肢的功率输出。然而，有人怀疑上半身对测得的功率输出有显著贡献，尽管目前尚不清楚具体情况，因此在测力评估过程中应考虑全身的去脂体重。为了验证这一想法，在高强度腿部蹬车测力测试（持续20秒；每千克总体重75克）期间，使用两种方案从11名受试者身上获取了机械功率输出指标：一种是标准的车把握持方式（有握持），另一种是旋后腕部方式（无握持）。在每次测试期间计算每个受试者的峰值机械功率、平均机械功率、疲劳指数和总机械功值，并使用配对学生t检验比较与两种方案相关的样本均值差异。有握持方案产生的峰值机械功率输出明显高于无握持方案（分别为886±124瓦和815±151瓦），这表明上半身对测得的腿部最大功率输出有显著贡献。作为量化腿部蹬车测力过程中上半身参与程度的第一步，在第十二名受试者进行每个测试方案时，测量了前臂肌肉组织的表面肌电图。在有握持的测力测试期间，前臂肌肉组织中的电活动强度即使不大于在100%最大自主握力计收缩期间记录的前臂肌肉组织的电活动强度，也是相似的，这表明在有握持的腿部测力测试期间前臂肌肉进行了最大等长收缩。这些发现表明，传统式腿部蹬车测力需要全身的肌肉参与。因此，研究人员在测力负荷分配和血源性代谢物分析方面都应注意这一点。
