Human Energy Expenditure in Anthropology and Beyond

Abstract

Humans have successfully inhabited every continent on this planet. Our ability to survive and thrive in such a wide range of environments is fascinating, particularly from an energetic perspective. As knowledge of human total energy expenditure (TEE, kcal day−1) has deepened, so too has the ability to interpret observable patterns in human metabolic physiology and apply these interpretations to our evolutionary history. This review examines the basic components of human TEE as well as the interactions among these components. This is followed by a discussion of two recent theories regarding limits on the amount of calories used and how those limits may mediate life‐history variables. Finally, this review provides a look ahead into the lesser explored areas of human TEE, suggesting future areas of research. The ability to measure how much energy humans expend and how they allocate that energy is a powerful tool that enables anthropologists to understand not only our past but also our present. [energy expenditure, thermoregulation, life history]

Erythroderma (exfoliative dermatitis). Part 2: energy homeostasis and dietetic management strategies

“…2 Situational factors such as thermoregulation, growth and immune costs may further influence final TEE. 3…”

“…Factors such as larger meal sizes, intake of carbohydrate and protein as opposed to fat, and a low‐fat plant‐based diet can increase energy expenditure from TEF 2 . Situational factors such as thermoregulation, growth and immune costs may further influence final TEE 3 …”

Sex differences and shifts in body composition, physical activity, and total energy expenditure across a 3‐month expedition

“…We found that across all individuals, there was no significant difference in TEE (kcal day À1 ) from early to later in the course. Recent research by Ocobock (2016aOcobock ( , 2020 in similar expedition settings suggests that as relative "newcomers" to this kind of highly challenging environment, the continuous exposure to high levels of physical activity while undergoing novel and intense ecological stress, leads to sustained total energy expenditure at very high levels, well over ~4000 kcal day À1 , over weeks and months without any tapering of energetic costs (Ocobock, 2016a(Ocobock, , 2020. Averaging across, subjects in our study maintained estimated TEE at ~4000-6000 kcal day À1 from early to late in the course.…”

“…Body mass fluctuation is more nuanced than the direct consumption/expenditure of calories and caloric intake and the macronutrient content consumed can help explain expenditure. However, the use of energy deposits and subsequent body composition changes can broadly point to energy expenditure exceeding energy intake and help infer energy status (Ocobock, 2020;Westerterp et al, 1992). When facing energy deficits, the body will preferentially burn fat stores and then begin to burn muscle (Ocobock, 2017) with likely functional implications for everyday activity.…”

“…In addition, while it is well understood that males and females have differential basal metabolic rates largely due to relatively greater body and fat-free mass in males (Johnstone et al, 2005;Manini, 2010;Ocobock, 2020), it is less known how total energy expenditure may differ by sex during and after acclimatization. Beyond basic differences in body composition and basal metabolic rate, some previous research suggests that there are potential differences in how males and females respond to extreme physiological demands, for example, such as males having higher dependency on carbohydrate utilization and increases in the heart's stroke volume in expedition settings thus increasing energy expenditure during demanding activities (Braun et al, 2000;Hattersley et al, 2020;Pettit et al, 1999).…”