Energy Balance Assessment Core

The Energy Balance Assessment Core (EBAC) has been an integral component of the University of Colorado NORC since 1997. The EBAC provides support for the measurement of components of energy balance (e.g., energy expenditure and intake) and for assessing consequences of alterations in energy balance (e.g., body composition, substrate oxidation). The Overarching Aim of the EBAC is to provide expertise and support for obesity- and nutrition-related basic, clinical, translational, and transdisciplinary research for NORC investigators at CU-AMC and its affiliates. Services of the EBAC have been and will continue to be essential for many NORC investigators.

Energy Balance Lab (EBL)
The Energy Balance Core (EBL) provides services to assess body composition, bone density, physical fitness, and energy expenditure values in research participants. Only CTRC-approved research protocols can request Energy Balance Core services.


1. Measurement of Body Composition and Bone Density. We offer DXA Total Body Scans to provide body composition information. Bone density is determined through Hip and Spine scans.

2. Measurement of Physical Fitness. We can perform maximal or submaximal graded exercise testing with VO2 values.

3. Measurement of Energy Expenditure and Substrate oxidation. We offer Whole Room Calorimeter or Resting Metabolic Rate (RMR) testing.

4. Measurement of Usual Physical Activity. We can help your study measure physical activity through the use of accelerometers.

5. Measurement of Isometric Knee test. EBL can obtain peak torque measurements during isometric knee strength testing using the HUMAC Norm Dynamometer.

For pricing information or to request services from Energy Balance please contact Jere Hamilton.

EBL small animal sub core
The small animal sub-core of the EBL provides support for PI’s who want to measure energy intake, energy intake, physical activity, and body composition in small animals. This is the only metabolic phenotyping core on campus, and the specialized equipment has been uniquely modified so that measures of energy balance can be acquired while assessing nutrient trafficking and metabolism. Although most of the work involves strains of rats and genetically modified mice, the equipment has also been used to study ground squirrels, pythons, and flies. The 400sqft IACUC-approved NORC animal satellite facility is used for long term housing, metabolic phenotyping, intake monitoring, nutrient tracer studies, rodent exercise, and other preclinical procedures.


1. Body Composition and Bone Density. To provide body composition information in live animals we offer both DXA and quantitative magnetic resonance (EchoMRI). Bone density can be determined with DXA through the use of small animal software. Post mortem body composition can also be determined in large organs with the EchoMRI.

2. Intake Monitoring. Intake monitoring can be performed by two methods. The more general and common method is to manually weigh the food, correcting for spillage over 24, 48, or 72hr periods while animals are housed in metabolic caging racks. The second method is BioDAQ, a real-time food intake monitoring system that measures the episodic feeding activity of singly housed lab animals in their home cage. Adlib, restrictive, or intermittent meal feeding can be achieved with automated gate closure following consumption of a given allotment of food.

3. Indirect Calorimetry. The EMC maintains two 8-chamber indirect calorimetry systems (1 rat, 1 mouse) within the NORC animal satellite facility for the determination of energy intake, energy expenditure, whole body fuel utilization, and both resting and activity energy expenditure. The mouse system is enclosed within a metabolic chamber that facilitates studies over a range of temperatures (4-30C).

4. Tracer Calorimetry. In concert with indirect calorimetry, stable or radio-labeled isotopes may be incorporated into the diet in order to examine nutrient oxidation, trafficking, and storage.

5. Physical activity. Daily physical activity is usually measured in concert with indirect calorimetry. Total, ambulatory, and non-ambulatory activities are recorded in real time.

6. Exercise Training. We maintain 4 Exer 3/6 Columbus Instruments treadmills within the animal satellite facility for training. Exercise energy expenditure can be determined on a single lane calorimetry treadmill.

For more information, please visit the Melanson Lab. For pricing information or to request services from Energy Balance, please contact Matthew Jackman

View Energy Balance Assessment Core Team