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Doubly Labelled Water: Theory and Practice
Acknowledgements. Preface. Part one: Introduction to energetics. Part two: Doubly-labelled water: theory. Part three: Doubly-labelled water: practice. Index.
Body size, energy metabolism and lifespan
  • J. Speakman
  • Biology, Medicine
  • Journal of Experimental Biology
  • 1 May 2005
A novel comparison using daily energy expenditure (DEE), rather than BMR, suggests that lifetime expenditure of energy per gram of tissue is NOT independent of body mass, and that tissue in smaller animals expends more energy before expiring than tissue in larger animals. Expand
The physiological costs of reproduction in small mammals
  • J. Speakman
  • Medicine, Biology
  • Philosophical Transactions of the Royal Society B…
  • 27 January 2008
Life-history trade-offs between components of fitness arise because reproduction entails both gains and costs, and knowledge of these physiological costs is currently at best described as rudimentary. Expand
Maximal heat dissipation capacity and hyperthermia risk: neglected key factors in the ecology of endotherms.
It is argued that the HDL is a major constraint operating on the expenditure side of the energy balance equation, and that processes that generate heat compete and trade-off within a total boundary defined by heat dissipation capacity, rather than competing for limited energy supply. Expand
AMPK is essential for energy homeostasis regulation and glucose sensing by POMC and AgRP neurons.
It is suggested that while AMPK plays a key role in hypothalamic function, it does not act as a general sensor and integrator of energy homeostasis in the mediobasal hypothalamus. Expand
The Cost of Living: Field Metabolic Rates of Small Mammals
The chapter has discussed results and provided an overview of database studied and has described factors influencing daily energy expenditure in mammals and links between FMR and RMR and sustainable metabolic scope. Expand
Oxidative stress as a cost of reproduction: Beyond the simplistic trade‐off model
The background to the oxidative stress hypothesis is explored, some of the complexities in testing it are highlighted, and it is concluded that the approach recently suggested to be least useful in this context (comparing reproducing to non‐reproducing animals) may in fact be the most powerful. Expand
Factors influencing variation in basal metabolic rate include fat-free mass, fat mass, age, and circulating thyroxine but not sex, circulating leptin, or triiodothyronine.
The data confirm that both FFM and FM are significant contributors to BMR, and suggest that previous links between circulating leptin concentrations and BMR occurred only because of inadequate control for the effects of FM. Expand
Energy balance and its components: implications for body weight regulation.
A panel composed of members with expertise in weight management, energy metabolism, physical activity, and behavior was convened to review the published scientific literature and to hear presentations from other experts in these fields. Expand
Physical activity and resting metabolic rate
It is suggested that exercise produces energetic benefits in other components of the daily energy budget, thus generating a net effect on energy balance much greater than the direct energy cost of the exercise alone. Expand