KEY WORDSEnergy intake, Energy expenditure, Energy storage
ABSTRACTEnergy capture and conversion is fundamental to human existence, and over the past three decades anthropologists have used a number of approaches which incorporate energetics measures in studies of human ecology. In particular, measures of community-level energy balances and flows have been used to study human subsistence within the adaptability framework. Recent advances in energetics methodology are considerable, making measurements more practicable and accurate. They include the following: the development of less invasive methods for the measurement of energy expenditure in the field; improvements in, and reevaluation of, older techniques for energy expenditure measurement; and an improved understanding of the physiological basis of adaptation to high and low energy intakes. This article describes and evaluates field methods currently available for estimating energy intake, expenditure, and storage.All three types of method can be used to examine energy balance over periods of more than a month, and energy nutritional stress in individuals and communities. Energy intake measures are the least accurate and most time-consuming, while anthropometric body composition methods are the most robust in a wide variety of field conditions. Energy expenditure methods are intermediate in accuracy, but they can be used to address issues of work output, physical performance, and metabolic adaptation, as well as short-term energy balance. Q 1992 Wiley-Liss, Inc.Nearly all aspects of human activity have energy implications (Harrison, 1982), and over the past three decades there has been considerable attention paid by anthropologists to the energetics of human ecology (Ellen, 1982;Lee, 1965;Little and Morren, 1976;Montgomery and Johnson, 1976;Morren, 1977;Ohtsuka, 1983;Rappaport, 1968). In particular, estimates of energy intakes, total expenditures, costs of physical activity, balances, and flows have been used in attempts to understand human subsistence within the adaptability framework (Bayliss-Smith, 1982; Bayliss-Smith and Feachem, 1977;Pimentel and Pimentel, 1979;Ulijaszek and Strickland, 1992). Several approaches have been attempted. These include: 1) analyses of how the need for dietary energy and the ways that it is obtained affect different aspects of human population biology or ecology (Haas and Pelletier, 1989;Thomas et al., 1982Thomas et al., ,1989Weitz et al., 1989); 2) examination of the implications of different subsistence and foraging strategies for fertility and biological fitness (Bertes, 1988; Hill and Kaplan, 1988a,b; Smith, 1979); and 3) the study of human responses and adaptations to seasonal energetic stresses (Abdullah, 1989; Brenton, 1988;Dugdale and Payne, 1986;Ferro-Luzzi, 1990a;Ferro-Luzzi et al., 1990; de Garine and Harrison, 1988; Hitchcock, 1988;Huss-Ashmore and Goodman;Huss-Ashmore and Thomas, 1988; de Garine 0 1992 Wiley-Liss, Inc.
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YEARBOOK OF PHYSICAL ANTHROPOLOGY[Vol. 35, 1992 and Koppert, 1988;Lawrence et al., 1989;...
