This article discusses the use of indirect calorimetry for the measurement of human energy expenditure. Quantification of energy expenditure during low efficiency walking (as depicted in the Monty Python sketch The Ministry of Silly Walks) is presented as an example of how physical activity recommendations could be met by exchanging ~11 minutes per day of normal walking with low efficiency walking—without requiring any further time commitment. Human energy expenditure involves the catabolism of macronutrients—mainly carbohydrates and fat—to carbon dioxide and water, which is coupled to the consumption of oxygen. Because this process produces heat, energy expenditure can be measured via direct calorimetry. This method requires a human calorimeter that is cost prohibitive and, more importantly, is limited in its capacity to measure energy expenditure from physical activity. Indirect calorimetry, which requires measurement of ventilation and gas exchange, has greater functionality with broader applications, and is the most widely used method of measuring human energy expenditure during physical activity. Historically, ventilation and gas exchange were assessed by collecting expired air in impermeable canvas (Douglas) bags or large calibrated spirometers and then measuring the concentrations of oxygen and carbon dioxide either chemically or with calibrated electronic gas analysers.1 Technology advances led to the development of automated systems that are now the standard for assessment of energy expenditure. Automated indirect calorimetry systems consist of a flow meter to measure ventilation, gas analysers to measure concentrations of CO2 …

中文翻译：

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测量人体能量消耗：公共卫生应用以对抗不活动

本文讨论了使用间接量热法测量人体能量消耗。低效率步行期间能量消耗的量化（如 Monty Python 草图 The Ministry of Silly Walks 中所述）作为一个示例，说明如何通过将每天约 11 分钟的正常步行与低效率步行交换来满足身体活动建议——无需任何进一步的时间承诺。人体能量消耗涉及常量营养素（主要是碳水化合物和脂肪）分解代谢为二氧化碳和水，这与氧气的消耗有关。由于此过程会产生热量，因此可以通过直接量热法测量能量消耗。这种方法需要一个成本高昂的人体量热器，更重要的是，其测量身体活动能量消耗的能力有限。间接量热法需要测量通风和气体交换，功能更强大，应用更广泛，是目前应用最广泛的测量人体运动能量消耗的方法。从历史上看，评估通气和气体交换的方法是在不透水的帆布（道格拉斯）袋或大型校准肺活量计中收集呼出的空气，然后用化学方法或校准的电子气体分析仪测量氧气和二氧化碳的浓度。 1技术进步导致了自动化系统现在是能量消耗评估的标准。自动间接量热法系统包括一个测量通风的流量计，