DESCRIPTION (adapted from the application): The objectives of the Core are to provide CNRU Affiliate Investigators access to state-of-the-art methods for measuring body composition and metabolic expenditure, as well as consultation and guidance in choosing among the methods. The methods that are available span a wide variety of possible clinical uses from small animal studies through small clinical studies to large field trials. This is important since there is no gold standard that is best under all conditions. Another objective of the Core is to attract investigators to become CNRU Affiliate Investigators. The Body Composition and Energy Expenditure Core evolved from a subcore of the Clinical Research Core at the suggestion of the last review panel. During the present grant period, this Core has been successful in its mission to assist Affiliate Investigators in studies involving body composition and energy metabolism. It has been utilized by more than 22 investigators and was instrumental in the successful application for new funding in 3 grants. In addition, it has been contributory to the decisions of several individuals to become Affiliate Investigators of the CNRU.