Carbohydrates (CHO) can play an important thermogenic role during shivering, but the effect of their availability on the use of other oxidative fuels is unclear. Using indirect calorimetry and tracer methods ([U-13C]glucose ingestion), we have determined the specific contributions of plasma glucose, muscle glycogen, proteins, and lipids to total heat production (Hprod) in men exposed to cold fo...

The aim of this study was to assess the validity of the RT3 accelerometer, and its inbuilt algorithm, in measuring inactivity, walking and running in children. Twenty children, aged 7-12 years, participated in the study. The RT3 was compared to physiological energy expenditure obtained via a wireless portable ergospirometric system. Data analysis was performed using Bland and Altman plots and P...

BACKGROUND An understanding of energy expenditure in hospitalized patients is necessary to determine optimal energy supply. The metabolic rate can be measured or estimated by equations, but estimation is by far the most common method. AIM This study tests the degree of agreement between measured resting energy expenditure by indirect calorimetry and predicted resting energy expenditure by Har...

BACKGROUND & AIMS Predictive equations for basal energy expenditure (BEE) derived from Caucasians tend to overestimate BEE in non-Caucasians. The aim of this study was to develop a more suitable method to estimate BEE in Japanese patients with diabetes using indices readily measured in clinical practice. METHODS BEE was measured by indirect calorimetry under a strict basal condition in 68 Jap...

BACKGROUND Accurate and comfortable methods are needed to determine resting energy expenditure (REE) in older people who are characterized by a lowered metabolic rate. The portable SenseWear® armband (SWA) body monitor, worn on the right upper arm, can easily be used by this age group in an ambulatory manner. OBJECTIVE The purpose of this study was to evaluate the reliability and accuracy of ...

Maximal oxygen uptake VO(2max)) is considered the optimal method to assess aerobic fitness. The measurement of VO(2max), however, requires special equipment and training. Maximal exercise testing with determination of maximal power output offers a more simple approach. This study explores the relationship between [Vdot]O(2max) and maximal power output in 247 children (139 boys and 108 girls) ag...

To characterize postprandial glucose disposal more completely, we used the tritiated water technique, a triple-isotope approach (intravenous [3-H(3)]glucose and [(14)C]bicarbonate and oral [6,6-(2)H(2)]glucose) and indirect calorimetry to assess splanchnic and peripheral glucose disposal, direct and indirect glucose storage, oxidative and nonoxidative glycolysis, and the glucose entering plasma...

A metabolic simulator capable of simulation of respiratory oxygen consumption (VO2) and carbon dioxide production (VCO2) for validation of indirect calorimetry systems is described. The metabolic simulator adds/removes respiratory gases by way of mass flow controllers to/from a physiologically realistic lung simulator (Michigan Instruments Inc. Training/Test Lung). The metabolic simulator and M...

To lower the risk of incorrectly feeding critically ill patients, indirect calorimetry (IC) is proposed as the most ideal method to evaluate energy expenditure and to establish caloric goals. New IC devices are progressively introduced but validation of this new generation remains challenging and arduous.

BACKGROUND Nonexercise models were developed to predict maximal oxygen consumption (VO2(max)). While these models are accurate, they don't consider smoking, which negatively impacts measured VO2(max). The purpose of this study was to examine the effects of smoking on both measured and predicted VO2(max). METHODS Indirect calorimetry was used to measure VO2(max) in 2,749 men and women. Physica...