Previous experiments showed reduction of basal metabolic rate (BMR) in birds facing energetic challenges. We alternately exposed two groups of red knots (Calidris canutus) to either 6 h or 22 h of food availability for periods of 22 d. Six h of access to food led to a 6%-10% loss of body mass over the first 8 d, with nearly all of the birds' daily energy expenditures supported by body nutrient ...

Two competing but nonexclusive hypotheses to explain the reduced basal metabolic rate (BMR) of mammals that live and forage underground (fossorial species) are examined by comparing this group with burrowing mammals that forage on the surface (semifossorial species). These hypotheses suggest that the low BMR of fossorial species either compensates for the enormous energetic demands of subterran...

From an evolutionary perspective, the high basal metabolic rate (BMR) of homeotherms is hypothesised to be a by-product of natural selection for effective parental care. We estimated daily milk output during two consecutive lactation bouts in mice divergently selected for high/low BMR and applied a cross-fostered design to control for potential differences in the between-line suckling abilities...

It has been proposed that intron and genome sizes in birds are reduced in comparison with mammals because of the metabolic demands of flight. To test this hypothesis, we examined the sizes of 14 introns in a nonflying relative of birds, the American alligator (Alligator mississippiensis), and in 19 flighted and flightless birds in 12 taxonomic orders. Our results indicate that a substantial fra...

Hypertension is an important global health issue and is currently increasing at a rapid pace in most industrializing nations. Although a number of risk factors have been linked with the development of hypertension, including obesity, high dietary sodium, and chronic psychosocial stress, these factors cannot fully explain the variation in blood pressure and hypertension rates that occurs within ...

Ageing is associated with a decline in basal metabolic rate (BMR) in many species, including humans. The evolutionary and physiological causes underlying the relationship between age and BMR are poorly understood. Studies of procellariiform seabirds may provide valuable insight because they have a longer maximum lifespan than expected from their body size and rates of energy metabolism. Such st...

Human pregnancy is associated with increased requirements for dietary energy and this increase may be partly offset by reductions in physical activity during gestation. Studies in well-nourished women have shown that the physical activity level (PAL), obtained as the total energy expenditure (TEE) divided by the BMR, decreases in late pregnancy. However, it is not known if this decrease is real...

Field metabolic rate (FMR), using the doubly labelled water (DLW) method, was measured in free-ranging adult kittiwakes (Rissa tridactyla) early and late in the chick-rearing period at Svalbard, Norway. Individual variation in FMR was analysed by comparing FMR with body mass, sex, nest attendance, chick age, brood size, and basal metabolic rate (BMR). Mean FMR of kittiwakes during the chick-rea...

BACKGROUND Dietary energy intake (DEI) is reported to be below recommended values in a large proportion of stable chronic haemodialysis patients, while energy requirement appears not to be very different from that in healthy subjects. Nevertheless, body mass has often been reported to be stable over time. We hypothesized that underestimation of habitual DEI by self-reporting of food intake coul...

Patients with Duchenne muscular dystrophy are so malnourished that energy supplementation is crucial. Their degree of energy deficiency was assessed as difference between their energy intake and their energy allowance, which were deduced from easily measured parameters. A significant, negative relationship was found between the basal metabolic rate (BMR) (Y, %, BMR/standard BMR) and body weight...