Basal metabolic rate in free-living tropical birds: the influence of phylogenetic, behavioral, and ecological factors

SummaryThe measurement of food intake has long been used to describe ‘adaptation’ to low energy intakes in certain tropical peoples. However, the methods available to quantify food intake are unlikely to reflect accurately real energy intakes in free living peoples. Alternatively, estimating energy expenditure shows some promise—particularly the measurement of basal metabolic rate (BMR). The BMR may be measured effectively in males, but females show wide intra-individual variation in BMR during their menstrual cycle, which makes BMR measurements more difficult to interpret in the context of adaptation. The use of double-labelled water may be the only method suitable to quantify and define ‘adaptation’ to low intakes in women.

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Relationship Between Energy Availability And Basal Metabolic Rate In Free-living Competitive Girl Runners

Medicine & Science in Sports & Exercise ◽

10.1249/01.mss.0000687524.96263.a8 ◽

2020 ◽

Vol 52 (7S) ◽

pp. 1090-1091

Author(s):

Norimitsu Kinoshita ◽

Eriko Uchiyama ◽

Kazuko Ishikawa-Takata ◽

Yuka Yamada ◽

Kenta Okuyama

Keyword(s):

Metabolic Rate ◽

Basal Metabolic Rate ◽

Energy Availability ◽

Free Living

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Thermal conductance and basal metabolic rate are part of a coordinated system for heat transfer regulation

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2013.1629 ◽

2013 ◽

Vol 280 (1767) ◽

pp. 20131629 ◽

Cited By ~ 12

Author(s):

Daniel E. Naya ◽

Lucía Spangenberg ◽

Hugo Naya ◽

Francisco Bozinovic

Keyword(s):

Heat Transfer ◽

Metabolic Rate ◽

Basal Metabolic Rate ◽

Structural Equation ◽

Thermal Conductance ◽

Ecological Factors ◽

Strong Positive Correlation ◽

Scale Invariant ◽

Physiological Variables ◽

Exogenous Factors

Thermal conductance measures the ease with which heat leaves or enters an organism's body. Although the analysis of this physiological variable in relation to climatic and ecological factors can be traced to studies by Scholander and colleagues, only small advances have occurred ever since. Here, we analyse the relationship between minimal thermal conductance estimated during summer ( C min ) and several ecological, climatic and geographical factors for 127 rodent species, in order to identify the exogenous factors that have potentially affected the evolution of thermal conductance. In addition, we evaluate whether there is compensation between C min and basal metabolic rate (BMR)—in such a way that a scale-invariant ratio between both variables is equal to one—as could be expected from the Scholander–Irving model of heat transfer. Our major findings are (i) annual mean temperature is the best single predictor of mass-independent C min . (ii) After controlling for the effect of body mass, there is a strong positive correlation between log 10 ( C min ) and log 10 (BMR). Further, the slope of this correlation is close to one, indicating an almost perfect compensation between both physiological variables. (iii) Structural equation modelling indicated that C min values are adjusted to BMR values and not the other way around. Thus, our results strongly suggest that BMR and thermal conductance integrate a coordinated system for heat regulation in endothermic animals and that summer conductance values are adjusted (in an evolutionary sense) to track changes in BMRs.

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Development of new predictive equations for basal metabolic rate in Iranian healthy adults: negligible effect of sex

International Journal for Vitamin and Nutrition Research ◽

10.1024/0300-9831/a000669 ◽

2020 ◽

pp. 1-10

Author(s):

Bahareh Nikooyeh ◽

Nastaran Shariatzadeh ◽

Ali Kalayi ◽

Maliheh Zahedirad ◽

Tirang R. Neyestani

Keyword(s):

Metabolic Rate ◽

Thyroid Function ◽

Basal Metabolic Rate ◽

Age Groups ◽

Thyroid Function Tests ◽

Anthropometric Measures ◽

Predictive Equations ◽

Normal Thyroid Function ◽

Asian People ◽

Predictive Formulas

Abstract. Some studies have reported inaccuracy of predicting basal metabolic rate (BMR) by using common equations for Asian people. Thus, this study was undertaken to develop new predictive equations for the Iranian community and also to compare their accuracy with the commonly used formulas. Anthropometric measures and thyroid function were evaluated for 267 healthy subjects (18–60 y). Indirect calorimetry (InCal) was performed only for those participants with normal thyroid function tests (n = 252). Comparison of predicted RMR (both kcal/d and kcal.kg.wt−1.d−1) using current predictive formulas and measured RMR revealed that Harris-Benedict and FAO/WHO/UNU significantly over-estimated and Mifflin-St. Jeor significantly under-estimated RMR as compared to InCal measurements. In stepwise regression analysis for developing new equations, the highest r2 (=0.89) was from a model comprising sex, height and weight. However, further analyses revealed that unlike the subjects under 30 y, the association between age and the measured RMR in subjects 30 y and plus was negative (r = −0.241, p = 0.001). As a result, two separate equations were developed for these two age groups. Over 80 percent of variations were covered by the new equations. In conclusion, there were statistical significant under- and over-estimation of RMR using common predictive equations in our subjects. Using the new equations, the accuracy of the calculated RMR increased remarkably.

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COMBINATION OF POTASSIUM PERCHLORATE AND PROPYLTHIOURACIL IN THE TREATMENT OF THYROTOXICOSIS

Acta Endocrinologica ◽

10.1530/acta.0.0570565 ◽

1968 ◽

Vol 57 (4) ◽

pp. 565-577 ◽

Cited By ~ 4

Author(s):

K. E. Røkke ◽

J. H. Vogt

Keyword(s):

Drug Therapy ◽

Side Effects ◽

Metabolic Rate ◽

Total Cholesterol ◽

Basal Metabolic Rate ◽

Combined Therapy ◽

Combined Treatment ◽

Control Measures ◽

Potassium Perchlorate ◽

Plasma Total Cholesterol

ABSTRACT A report is given on 95 thyrotoxic patients treated with a combination of 400 mg propylthiouracil and 400 mg of potassium perchlorate. Perchlorate was stopped when a marked remission of symptoms was obtained, on an average after less than 7 weeks. Euthyroidism was found on an average after 7.2 weeks. The basal metabolic rate, PBI, plasma total cholesterol and weight showed a fairly rapid normalization. Thirteen of the 95 patients were given radio-iodine therapy shortly before drug therapy was started. The remaining 82 cases were grouped together with the 23 cases previously reported. Of the total of 105 cases, 96 became euthyroid on combined therapy. For the frequency of side-effects, the thirteen cases mentioned above were included, giving a total of 118 cases. Eight cases showed an increase in goitre size and 15 cases had other side-effects, of which three were granulocytopenia due to propylthiouracil. The possibility of a higher frequency of mainly minor side-effects on combined therapy has to be balanced against the seemingly rapid and reliable therapeutic effect. Combined treatment, perhaps with even smaller doses than reported here, can be recommended in selected cases of thyrotoxicosis where a shortening of the thyrotoxic state seems of importance, or possibly where difficulties due to iodine exposure may be anticipated, provided adequate control measures are taken.

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