Simulated weightlessness alters the nycthemeral distribution of energy expenditure in rats

2001 ◽  
Vol 204 (23) ◽  
pp. 4107-4113
Author(s):  
Stéphane Blanc ◽  
Alain Géloën ◽  
Sylvie Normand ◽  
Claude Gharib ◽  
Laurence Somody

SUMMARY The energy metabolism adaptations to simulated weightlessness in rats by hindlimb tail suspension are unknown. 12 male rats were assigned to 7 days of isolation, 7 days of habituation to the suspension device, 10 days of simulated weightlessness, and 3 days of recovery. The 24-hour energy expenditure was measured by continuous indirect calorimetry. We calculated the 12-hour energy expenditure during the active (night) and inactive (day) periods, the minimal observed metabolic rates with the day values taken as an index of the basal metabolic rate, and the non-basal energy expenditure representing the cost of physical activity plus the diet-induced thermogenesis. Suspension did not change the mean 24-hour energy expenditure (360.8±15.3 J min–1 kg–0.67), but reduced the night/day difference by 64 % (P<0.05) through a concomitant drop in night-energy expenditure and increase in day values. The difference between night and day minimal metabolic rates was reduced by 81 % (P<0.05), and the transient rise in day values suggests an early and moderate basal metabolic rate increase (9 %). An overall 19 % reduction in non-basal energy expenditure was observed during simulated weightlessness (P<0.05), which was mainly attributable to a reduction in the cost of physical activity. 3 days of recovery restored the night/day differences but increased the 24-hour energy expenditure by 10 % (P<0.05). In conclusion, hindlimb tail suspension in rats did not alter the 24-hour energy expenditure, but it transiently increased the basal metabolic rate, and altered both the energy expended on physical activity and the nycthemeral distribution of motor activity. These data suggest that the circadian rhythms of energy expenditure are affected during simulated weightlessness.

1961 ◽  
Vol 16 (6) ◽  
pp. 982-990 ◽  
Author(s):  
Pietro O. Bramante

Oxygen consumption (Vo2) and spontaneous muscular activity of albino rats, recorded with apparatus previously described and quantitated with a new technique, exhibited highly significant correlations when paired in successive 10-min periods with a 5-min lag of Vo2 ( y) in respect to spontaneous muscular activity ( x). Since fasting and nonfasting male rats of different weights (range: 156—462 g) showed at perfect rest a quite narrow scatter of metabolic rates ( y = yaKgb ± 6% se) and since y was linearly correlated with x (se = 7.1% fasting; 5.5% nonfasting), theoretical Vo2 values could be predicted from y = Kgyb( m + nx) when the appropriate value of b, experimentally found (in this case 0.48), was used. In two-thirds of the observations the lowest 5-min values of Vo2 did not represent the true basal metabolic rate of the animal since they coincided with variable amounts of spontaneous activity. Data show that the basal metabolic rate of the albino rat is more predictable than generally admitted. Submitted on May 26, 1961


Author(s):  
Vincenzo De Geronimo ◽  
Rossella Cannarella ◽  
Sandro La Vignera

Background: Thyroid disease and obesity are very common clinical conditions in the general population. They can occur together in the same subject, but their relationship does not seem to be exclusively stochastic. Aim: We critically reviewed the evidence of the literature in the attempt to provide explanation for this association, in order to understand the possible benefits of levothyroxine therapy in euthyroid obese patients. Results: A low energy expenditure rate can lead to obesity. Maintaining Basal Metabolic Rate (BMR) is the main cause of energy expenditure for the body, which is regulated by thermogenesis. Thyroid hormone receptors (TR) play different roles in the induction of thermogenetic mechanisms: TRα is fundamental to induce thermogenesis, TRβ triggers the expression of uncoupling protein 1(UCP1). Despite such mechanisms, there is not currently evidence to treat subjects suffering from obesity with thyroid hormones. Conclusion: Replacement therapy should be reserved to patients with obvious signs of subclinical or clinical hypothyroidism. Definitions: Basal metabolic rate (BMR) or basal energy expenditure (BEE): measurement obtained under total inactivity and controlled research conditions; resting energy expenditure (REE): measurement obtained when an individual is sitting quietly (is mildly higher than BMR/BEE).


2020 ◽  
Vol 5 (2) ◽  
Author(s):  
I Putu Agus Dharma Hita ◽  
B. M. Wara Kushartanti ◽  
Fitri Agung Nanda

Physical activity, nutritional status, and total energy expenditure are important components of a human. The purpose of this study was to find out the depiction of physical activity, nutritional status, basal metabolic rate, and total energy expenditure of Indonesia migrant workers during Covid-19 pandemic. The study was a survey study with a descriptive design. The samples were 86 Indonesia migrant workers. The instrument used was the 24 hour recall physical activity sheet for 14 days. The result of the study showed that: 88% of male samples and 95% of female samples gained physical activity level score in low category. The PAL score of the male samples was 1.56, while the PAL score of female samples was 1.52. Related to body mass index, 51% of Indonesia migrant workers were in the normal category; 27% were in the overweight category; 17% were in the Obese I Category, and 5% were in the Obese II category. 22 Indonesia migrant workers in overweight category had low physical activity category, 15 persons in Obesity I category had low physical activity category, and 4 persons in Obese II category. The average of the BMR of the samples during the quarantine, due to Covid-19 pandemic, was 1669 kkal/day for male and 1335 kkal/day for female. The average of total energy expenditure of the samples during Covid-19 quarantine was 2595 kkal/day for male and 2031 kkal/day for female. The physical activity level was low, the nutrition status was normal, total energy expenditure was low, the BMR of the sample was dominated by age factor, sex, and weight of the sample. The result of the study was expected to be a reference of regional and other quarantine systems to improve the immunity system during the 14 days of quarantine.


1995 ◽  
Vol 73 (4) ◽  
pp. 571-581 ◽  
Author(s):  
Daphne L.E. Pannemans ◽  
Klaas R. Westerterp

Energy expenditure, and therefore energy requirement, generally decreases with advancing age because of a decrease in basal metabolic rate (BMR) and physical activity. The aim of the present study was to measure total energy expenditure (EE) and activity level in a group of healthy elderly (sixteen men aged 71·3 (SD 4·9) years; ten women aged 67·6 (SD 4·1) years) and young adults (nineteen men aged 30·4 (SD 5·0) years; ten women aged 27·2 (SD 3·9) years) by using the doubly-labelled water method in combination with measurements of BMR. Age-related differences in body composition and their relationship to BMR and activity level were studied. EE was lower in elderly compared with young adults, partly due to a significantly lower BMR. The lower BMR was not fully explained by the lower fat-free mass (FFM) in the elderly. Energy expended (MJ/d) on activity was higher for the younger subjects although there was no significant difference in the physical activity index (PAI = EE/BMR) between the two age groups. The effect of physical activity level is twofold: first it has a positive effect on the BMR, and second it has a positive effect on the FFM. Both effects involve an increase in the total EE with an increased level of physical activity. At energy balance this will lead to increased energy and nutrient intake, making especially the elderly less vulnerable to inadequate energy and nutrient intake.


1978 ◽  
Vol 35 (6) ◽  
pp. 816-821 ◽  
Author(s):  
J. R. Brett ◽  
J. M. Blackburn

The metabolic rate of spiny dogfish, Squalus acanthias, was determined in both a tunnel respirometer and a large, covered, circular tank (mass respirometer). Swimming performance was very poor in the respirometer, so that a power–performance curve could not be established. Instead, resting metabolic rates were determined, with higher rates induced by causing heavy thrashing (active metabolism). Routine metabolic rates were measured for the spontaneous activity characterizing behavior in the circular tank. For fish of 2 kg mean weight, the metabolic rates at 10 °C were 32.4 ± 2.6 SE (resting), 49.2 ± 5.0 SE (routine), and 88.4 ± 4.6 SE (active) mg O2∙kg−1∙h−1. Assuming that the routine rate represents a general energy expenditure in nature, this is equivalent to metabolizing about 3.8 kcal∙kg−1∙d−1 (15.9 × 103 J∙kg−1∙d−1). Key words: dogfish, metabolic rates, energetics, respiration


1997 ◽  
Vol 36 (4) ◽  
pp. 310-312 ◽  
Author(s):  
F. Thielecke ◽  
J. Möseneder ◽  
A. Kroke ◽  
K. Klipstein-Grobusch ◽  
H. Boeing ◽  
...  

2021 ◽  
Author(s):  
Patrick Mullie ◽  
Pieter Maes ◽  
Laurens van Veelen ◽  
Damien Van Tiggelen ◽  
Peter Clarys

ABSTRACT Introduction Adequate energy supply is a prerequisite for optimal performances and recovery. The aims of the present study were to estimate energy balance and energy availability during a selection course for Belgian paratroopers. Methods Energy expenditure by physical activity was measured with accelerometer (ActiGraph GT3X+, ActiGraph LLC, Pensacola, FL, USA) and rest metabolic rate in Cal.d−1 with Tinsley et al.’s equation based on fat-free mass = 25.9 × fat-free mass in kg + 284. Participants had only access to the French individual combat rations of 3,600 Cal.d−1, and body fat mass was measured with quadripolar impedance (Omron BF508, Omron, Osaka, Japan). Energy availability was calculated by the formula: ([energy intake in foods and beverages] − [energy expenditure physical activity])/kg FFM−1.d−1, with FFM = fat-free mass. Results Mean (SD) age of the 35 participants was 25.1 (4.18) years, and mean (SD) percentage fat mass was 12.0% (3.82). Mean (SD) total energy expenditure, i.e., the sum of rest metabolic rate, dietary-induced thermogenesis, and physical activity, was 5,262 Cal.d−1 (621.2), with percentile 25 at 4,791 Cal.d−1 and percentile 75 at 5,647 Cal.d−1, a difference of 856 Cal.d−1. Mean daily energy intake was 3,600 Cal.d−1, giving a negative energy balance of 1,662 (621.2) Cal.d−1. Mean energy availability was 9.3 Cal.kg FFM−1.d−1. Eleven of the 35 participants performed with a negative energy balance of 2,000 Cal.d−1, and only five participants out of 35 participants performed at a less than 1,000 Cal.d−1 negative energy balance level. Conclusions Energy intake is not optimal as indicated by the negative energy balance and the low energy availability, which means that the participants to this selection course had to perform in suboptimal conditions.


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