scholarly journals Evidence of negative energy balance using doubly labelled water in elite Kenyan endurance runners prior to competition

2006 ◽  
Vol 95 (1) ◽  
pp. 59-66 ◽  
Author(s):  
Barry W. Fudge ◽  
Klaas R. Westerterp ◽  
Festus K. Kiplamai ◽  
Vincent O. Onywera ◽  
Michael K. Boit ◽  
...  
Keyword(s):  
Energy Balance ◽  
Energy Intake ◽  
Body Mass ◽  
Negative Energy ◽  
Negative Energy Balance ◽  
Endurance Running ◽  
Doubly Labelled Water ◽  
Endurance Runners ◽  
Intense Training ◽  
Heavy Training

Previous studies have found Kenyan endurance runners to be in negative energy balance during training and prior to competition. The aim of the present study was to assess energy balance in nine elite Kenyan endurance runners during heavy training. Energy intake and expenditure were determined over 7d using weighed dietary intake and doubly labelled water, respectively. Athletes were on average in negative energy balance (mean energy intake 13 241 (SD 1330) kJ/d v. mean energy expenditure 14 611 (SD 1043) kJ/d; P=0·046), although there was no loss in body mass (mean 56·0 (SD 3·4) kg v. 55·7 (SD 3·6) kg; P=0·285). The calculation of underreporting was 13; (range −24 to +9%) and almost entirely accounted for by undereating (9% (range −55 to +39%)) as opposed to a lack of significant underrecording (i.e. total water intake was no different from water loss (mean 4·2 (SD 0·6) l/d v. 4·5 (SD 0·8) l/d; P=0·496)). Fluid intake was modest and consisted mainly of water (0·9 (SD 0·5) l/d) and milky tea (0·9 (SD 0·3) l/d). The diet was high in carbohydrate (67·3 (SD 7·8) %) and sufficient in protein (15·3 (SD 4·0) %) and fat (17·4 (SD 3·9) %). These results confirm previous observations that Kenyan runners are in negative energy balance during periods of intense training. A negative energy balance would result in a reduction in body mass, which, when combined with a high carbohydrate diet, would have the potential in the short term to enhance endurance running performance by reducing the energy cost of running.

Energy Balance and Energy Availability During a Selection Course for Belgian Paratroopers

2021 ◽  
Author(s):  
Patrick Mullie ◽  
Pieter Maes ◽  
Laurens van Veelen ◽  
Damien Van Tiggelen ◽  
Peter Clarys
Keyword(s):  
Physical Activity ◽  
Energy Balance ◽  
Energy Expenditure ◽  
Metabolic Rate ◽  
Energy Intake ◽  
Rest Metabolic Rate ◽  
Negative Energy ◽  
Fat Free Mass ◽  
Negative Energy Balance ◽  
Energy Availability

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.

Evidence Of Negative Energy Balance In Elite Kenyan Endurance Runners During Intense High-altitude Training

2005 ◽  
Vol 37 (Supplement) ◽  
pp. S142
Author(s):  
Barry Fudge ◽  
Klaas R. Westerterp ◽  
Festus K. Kiplamai ◽  
Vincent O. Onywera ◽  
Michael K. Boit ◽  
...  
Keyword(s):  
Energy Balance ◽  
High Altitude ◽  
Negative Energy ◽  
Negative Energy Balance ◽  
Altitude Training ◽  
Endurance Runners

Evidence Of Negative Energy Balance In Elite Kenyan Endurance Runners During Intense High-altitude Training

2005 ◽  
Vol 37 (Supplement) ◽  
pp. S142
Author(s):  
Barry Fudge ◽  
Klaas R. Westerterp ◽  
Festus K. Kiplamai ◽  
Vincent O. Onywera ◽  
Michael K. Boit ◽  
...  
Keyword(s):  
Energy Balance ◽  
High Altitude ◽  
Negative Energy ◽  
Negative Energy Balance ◽  
Altitude Training ◽  
Endurance Runners

Hypothalamic regulation of energy homeostasis when consuming diets of different energy concentrations: Comparison between Tibetan and Small-tailed Han sheep

2021 ◽  
pp. 1-25
Author(s):  
Xiaoping Jing ◽  
Yamin Guo ◽  
Allan Degen ◽  
Wenji Wang ◽  
Jingpeng Kang ◽  
...  
Keyword(s):  
Body Weight ◽  
Energy Balance ◽  
Energy Intake ◽  
Energy Homeostasis ◽  
Negative Energy ◽  
Negative Energy Balance ◽  
Positive Energy ◽  
Tibetan Sheep ◽  
Protein Expressions ◽  
Positive Energy Balance

Abstract Seasonal energy intake of Tibetan sheep on the harsh Qinghai-Tibetan Plateau (QTP) fluctuates greatly and is often well below maintenance requirements. The aim of this study was to gain insight into how the hypothalamus regulates energy homeostasis in Tibetan and Small-tailed Han sheep. We compared Tibetan and Small-tailed Han sheep (n=24 of each breed), which were offered one of four diets that differed in digestible energy (DE) densities: 8.21, 9.33, 10.45 and 11.57 MJ/kg dry matter. Sheep were weighed every two weeks, and it was assumed that the change in body weight reflected the change in energy balance. The arcuate nucleus of the hypothalamus in Tibetan sheep had greater protein expressions of neuropeptide Y (NPY) and agouti-related peptide (AgRP) when in negative energy balance, but lesser protein expressions of proopiomelanocortin (POMC) and cocaine and amphetamine-regulated transcript (CART) when in positive energy balance than Small-tailed Han sheep. As a result, Tibetan sheep had a lesser body weight (BW) loss when in negative energy balance and stored more energy and gained more BW when in positive energy balance than Small-tailed Han sheep with the same dietary intake. Moreover, in the hypothalamic AMPK regulation pathway, Tibetan sheep had greater AMPKα2 protein expression than Small-tailed Han sheep, which supported the premise of a better ability to regulate energy homeostasis and better growth performance. These differences in the hypothalamic NPY/AgRP, POMC/CART and AMPK pathways between breeds conferred an advantage to the Tibetan over Small-tailed Han sheep to cope with low energy intake on the harsh QTP.

scholarly journals Negative energy balance plays a major role in the IGF-I response to exercise training

2004 ◽  
Vol 96 (1) ◽  
pp. 276-282 ◽  
Author(s):  
Dan Nemet ◽  
Peter H. Connolly ◽  
Andria M. Pontello-Pescatello ◽  
Christie Rose-Gottron ◽  
Jennifer K. Larson ◽  
...  
Keyword(s):  
Energy Balance ◽  
Exercise Training ◽  
Energy Intake ◽  
Binding Protein ◽  
Negative Energy ◽  
Negative Energy Balance ◽  
Positive Energy ◽  
Igf I ◽  
Igf Binding ◽  
Igf Binding Protein

Circulating IGF-I is correlated with fitness, but results of prospective exercise training studies have been inconsistent, showing both increases and decreases in IGF-I. We hypothesized that energy balance, often not accounted for, is a regulating variable such that training plus an energy intake deficit would cause a reduction in IGF-I, whereas training plus energy intake excess would lead to an increased IGF-I. To test this, 19 young, healthy men completed a 7-day strenuous exercise program in which they were randomly assigned to either a positive energy balance [overfed (OF), n = 10] or negative energy balance [underfed (UF), n = 9] group. IGF-I (free and total), insulin, and IGF-binding protein-1 were measured before, during, and 1 wk after the training. Weight decreased in the UF subjects and increased in the OF subjects. Free and total IGF-I decreased substantially in the UF group ( P < 0.0005 for both), but, in the OF group, IGF-I remained unchanged. The UF group also demonstrated an increase in IGF-binding protein-1 ( P < 0.027), whereas glucose levels decreased ( P < 0.0005). In contrast, insulin was reduced in both the OF and UF exercise-training groups ( P < 0.044). Finally, within 7 days of the cessation of the diet and training regimen, IGF-I and IGF-binding protein-1 in the UF group returned to preintervention levels. We conclude that energy balance during periods of exercise training influences circulating IGF-I and related growth mediators. Exercise-associated mechanisms may inhibit increases in IGF-I early in the course of a training protocol, even in overfed subjects.

scholarly journals The feeding microstructure of male and female mice

PLoS ONE ◽  
2021 ◽  
Vol 16 (2) ◽  
pp. e0246569
Author(s):  
Yakshkumar Dilipbhai Rathod ◽  
Mauricio Di Fulvio
Keyword(s):  
Energy Balance ◽  
Energy Intake ◽  
Negative Energy ◽  
Meal Size ◽  
Negative Energy Balance ◽  
Dependent Manner ◽  
Eating Time ◽  
Male And Female ◽  
Female Mice ◽  
Old Females

The feeding pattern and control of energy intake in mice housed in groups are poorly understood. Here, we determined and quantified the normal feeding microstructure of social male and female mice of the C57BL/6J genetic background fed a chow diet. Mice at 10w, 20w and 30w of age showed the expected increase in lean and fat mass, being the latter more pronounced and variable in males than in females. Under ad libitum conditions, 20w and 30w old females housed in groups showed significantly increased daily energy intake when adjusted to body weight relative to age-matched males. This was the combined result of small increases in energy intake during the nocturnal and diurnal photoperiods of the day without major changes in the circadian pattern of energy intake or spontaneous ambulatory activity. The analysis of the feeding microstructure suggests sex- and age-related contributions of meal size, meal frequency and intermeal interval to the control of energy intake under stable energy balance, but not under negative energy balance imposed by prolonged fasting. During the night, 10-20w old females ate less frequently bigger meals and spent more time eating them resulting in reduced net energy intake relative to age-matched males. In addition, male and female mice at all ages tested significantly shortened the intermeal interval during the first hours of re-feeding in response to fasting without affecting meal size. Further, 20-30w old males lengthened their intermeal interval as re-feeding time increased to reach fed-levels faster than age-matched females. Collectively, our results suggest that the physiological mechanisms controlling meal size (satiation) and the non-eating time spent between meals (satiety) during stable or negative energy balance are regulated in a sex- and age-dependent manner in social mice.

Energy expenditure climbing Mt. Everest

1992 ◽  
Vol 73 (5) ◽  
pp. 1815-1819 ◽  
Author(s):  
K. R. Westerterp ◽  
B. Kayser ◽  
F. Brouns ◽  
J. P. Herry ◽  
W. H. Saris
Keyword(s):  
Weight Loss ◽  
Body Composition ◽  
Energy Balance ◽  
Energy Expenditure ◽  
Metabolic Rate ◽  
High Altitude ◽  
Energy Intake ◽  
Negative Energy ◽  
Negative Energy Balance ◽  
The Alps

Weight loss is a well-known phenomenon at high altitude. It is not clear whether the negative energy balance is due to anorexia only or an increased energy expenditure as well. The objective of this study was to gain insight into this matter by measuring simultaneously energy intake, energy expenditure, and body composition during an expedition to Mt. Everest. Subjects were two women and three men between 31 and 42 yr of age. Two subjects were observed during preparation at high altitude, including a 4-day stay in the Alps (4,260 m), and subsequently during four daytime stays in a hypobaric chamber (5,600–7,000 m). Observations at high altitude on Mt. Everest covered a 7- to 10-day interval just before the summit was reached in three subjects and included the summit (8,872 m) in a fourth. Energy intake (EI) was measured with a dietary record, average daily metabolic rate (ADMR) with doubly labeled water, and resting metabolic rate (RMR) with respiratory gas analysis. Body composition was measured before and after the interval from body mass, skinfold thickness, and total body water. Subjects were in negative energy balance (-5.7 +/- 1.9 MJ/day) in both situations, during the preparation in the Alps and on Mt. Everest. The loss of fat mass over the observation intervals was 1.4 +/- 0.7 kg, on average two-thirds of the weight loss (2.2 +/- 1.5 kg), and was significantly correlated with the energy deficit (r = 0.84, P < 0.05). EI on Mt. Everest was 9–13% lower than during the preparation in the Alps.(ABSTRACT TRUNCATED AT 250 WORDS)

GLUCOSE METABOLISM IN FAT AND THIN ADULT SHEEP

1984 ◽  
Vol 64 (4) ◽  
pp. 825-832 ◽  
Author(s):  
M. A. McNIVEN
Keyword(s):  
Energy Balance ◽  
Glucose Metabolism ◽  
Energy Intake ◽  
Negative Energy ◽  
Pool Size ◽  
Metabolizable Energy ◽  
Negative Energy Balance ◽  
Body Fatness ◽  
Feeding Level ◽  
Metabolizable Energy Intake

The effect of body fatness on glucose metabolism was studied in six adult crossbred wethers divided into two groups weighing 90 kg (fat) or 55 kg (thin). Glucose turnover measurements were made using 6-3H-glucose by single injection at four levels of metabolizable energy intake: high, 17 MJ/day; intermediate, 10 MJ/day; low, 6 MJ/day; and fasting for both thin and fat groups. The greatest group differences occurred at the high feeding level. Body pool size and glucose space were significantly lower (P < 0.001) for the fat sheep and were reduced at fasting for both fatness levels. The mean irreversible loss rate was not affected by body fatness but was significantly affected (P < 0.001) by feeding level. Glucose recycled as a proportion of total entry rate was significantly affected by body fatness and was dependent on a positive or negative energy balance. When in negative energy balance the sheep maintained blood glucose within the normal range by recycling up to four times more glucose than was utilized. It appears that rate of glucose synthesis is related to energy balance and metabolizable energy intake. A tendency toward insulin insensitivity in the fat sheep could be related to high levels of recycling, and a greater glucose drain or prolonged fast could be more serious with the decreased glucose pool size and space. Key words: Glucose metabolism, ruminant, obese, energy balance

Sign in / Sign up

Export Citation Format

Share Document