Background: Metabolic carts measure the carbon dioxide produced and oxygen consumed from the breath in order to assess metabolic fuel usage (carbohydrates vs. fats). However, these systems are expensive, time-consuming, and only available in the clinic. A small hand-held device capable of measuring metabolic fuel via CO2 from exhaled air has been developed. Objective: To evaluate the validity of a novel hand-held device (Lumen ^®) for measuring metabolic fuel utilization in healthy young adults. Methods: Metabolic fuel usage was assessed in healthy participants (n = 33; age: 23.1 ± 3.9 y) via respiratory exchange ratio (RER) values from the "gold-standard" metabolic cart as well as %CO2 from the Lumen device. Measurements were performed at rest in two conditions, fasting, and after consuming 150 grams of glucose in order to determine changes in metabolic fuel. Reduced major axis regression was performed as well as Bland-Altman plots and linear regressions to test for agreement between RER and Lumen %CO2. Results: Both RER and Lumen %CO2 significantly increased after glucose intake compared with fasting conditions (P < .0001). Regression analyses and Bland-Altman plots revealed an agreement between the two measurements with a systematic bias resulting from the nature of the different units. Conclusions: This study shows the validity of Lumen^® to estimate metabolic fuel utilization in a comparable manner with the "gold-standard" metabolic cart, providing the ability for real-time metabolic information for users under any circumstances.

中文翻译：

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Lumen®手持式新陈代谢装置可测量健康年轻人的燃油利用率

背景：代谢推车测量呼吸中产生的二氧化碳和消耗氧气，以评估新陈代谢的燃料使用量（碳水化合物与脂肪）。但是，这些系统昂贵，费时，并且只能在诊所中使用。已经开发出一种小型手持设备，该手持设备能够通过呼出空气中的CO2来测量代谢燃料。目的：探讨一种新型的手持式装置（流明的有效性 ^®在健康的年轻人测量代谢燃料利用率）。方法：在健康参与者（n = 33；年龄：23​​.1±3.9 y）中，通过“黄金标准”代谢推车的呼吸交换率（RER）值和流明仪的％CO2评估了代谢燃料的使用。为了确定代谢燃料的变化，在休息，禁食和消耗了150克葡萄糖这两种条件下进行了测量。执行减少的主轴回归以及Bland-Altman图和线性回归以测试RER和流明％CO2之间的一致性。结果：与禁食相比，葡萄糖摄入后RER和流明％CO2均显着增加（P <.0001）。回归分析和Bland-Altman图揭示了两次测量之间的一致性，并且由于不同单位的性质而产生系统性偏差。结论：这项研究显示流明的有效性^®与“黄金标准”代谢车估计类似的方式代谢燃料利用率，提供实时代谢信息的能力在任何情况下的用户。