Weight loss and changes in body composition at high altitude

1984 ◽  
Vol 57 (5) ◽  
pp. 1580-1585 ◽  
Author(s):  
S. J. Boyer ◽  
F. D. Blume

Little is known about weight loss and changes in body composition at extreme altitude. As part of the American Medical Research Expedition to Everest in 1981 we measured body weight, body fat, limb circumferences, dietary intake, 72-h stool fats, and 5-h urine xylose excretion at various altitudes on Caucasian and Sherpa expedition members. In Caucasians, loss of body fat accounted for 70.5% of the mean 1.9-kg weight loss during the approach march at moderate altitude but for only 27.2% of the mean 4.0-kg weight loss during residence above 5,400 m. There was a significant proportionate decrease in arm and leg circumferences during residence above 5,400 m (1.5 and 2.9 cm, respectively). On the other hand, Sherpas, who arrived in Base Camp with half as much body fat as members (9.1% vs. 18.4%), maintained weight and limb circumferences during residence above 5,400 m. Fat absorption decreased 48.5% in three subjects, and xylose excretion decreased 24.3% in six of seven subjects at 6,300 m relative to sea level. It appears that muscle catabolism and malabsorption contribute significantly to weight loss at high altitude. High percent body fat does not protect against loss of muscle tissue. Sherpas do not appear susceptible to some of the changes affecting Caucasians.

2020 ◽  
Vol 17 (1) ◽  
Author(s):  
Yang Niu ◽  
Xue-lin Zhao ◽  
Hui-juan Ruan ◽  
Xiao-meng Mao ◽  
Qing-ya Tang

Abstract Background Current adult studies suggest that uric acid (UA) is associated with body fat, but the relationship in obese children is unclear. Thus, we aim to evaluate the association between uric acid and body composition of obese children. Methods A total of 79 obese children were included in this study, and 52 children (34 boys and 18 girls) underwent a 6-week weight loss camp, including 34 boys and 18 girls. Six-week weight-loss interventions were performed on all participants through aerobic exercise and appropriate dietary control. Laboratory tests and body composition were collected before and after the intervention. Results Before the intervention, correlation analysis demonstrated that uric acid was positively correlated with height, weight, body mass index (BMI), waist circumference, hip circumference, fat mass (FM), and free fat mass (FFM) with adjusting for age and gender (P < 0.05). After 6 weeks of intervention, the participants gained 3.12 ± 0.85 cm in height, body fat percentage decreased by 7.23 ± 1.97%, and lost 10.30 ± 2.83 kg in weight. Univariate and multivariate analysis indicated that uric acid at baseline was associated with FM reduction during weight loss (P < 0.05). Conclusions This study is the first report that uric acid is associated with BMI and FM, and may play an important role in the reduction of FM during weight loss in obese children and adolescents. The interaction between UA and adiposity factors and its underlying mechanisms need to be further explored. Trial registration This study was registered in Clinical Trials.gov (NCT03490448) and approved by the Ethics Committee of Xinhua Hospital, Shanghai Jiao Tong University School of Medicine.


2015 ◽  
Vol 40 (7) ◽  
pp. 695-702 ◽  
Author(s):  
Eve Normandin ◽  
Eric Doucet ◽  
Rémi Rabasa-Lhoret ◽  
Martin Brochu

Obesity is a heterogeneous condition, since the metabolic profile may differ greatly from one individual to another. The objective of this study was to compare the effect of a 6-month diet-induced weight loss program on body composition and the metabolic profile in obese individuals displaying different obesity phenotypes. Secondary analyses were done on 129 obese (% body fat: 46% ± 4%) postmenopausal women (age: 57 ± 4 years). Outcome measures included body composition, body fat distribution, glucose homeostasis, fasting lipids, and blood pressure. Obesity phenotypes were determined based on lean body mass (LBM) index (LBMI = LBM/height2) and visceral fat (VF) accumulation, as follows: 1, lower VF and lower LBMI (n = 35); 2, lower VF and higher LBMI (n = 19); 3, higher VF and lower LBMI (n = 14); and 4, higher VF and higher LBMI (n = 61). All groups had significantly improved measures of body composition after the intervention (P < 0.0001). Greater decreases in LBM and LBMI were observed in the higher LBMI groups than in the lower LBMI groups (P < 0.0001). Similarly, decreases in VF were greater in the higher VF groups than in the lower VF groups (P < 0.05). Overall, fasting insulin levels and glucose disposal improved following the intervention, with higher LBMI groups showing a trend for greater improvements (P = 0.06 and 0.07, respectively). Overall, no difference was observed among the different obesity phenotypes regarding improvements in the metabolic profile in response to weight loss. Individuals displaying higher VF or higher LBMI at baseline experienced significantly greater decreases for these variables after the intervention.


1978 ◽  
Vol 44 (1) ◽  
pp. 17-20 ◽  
Author(s):  
D. B. Dill ◽  
L. F. Soholt ◽  
J. D. Morris

Kangaroo rats deprived of food ran themselves to death in 48 h in wheel cages. Despite the loss of 14.5% of body weight the ratio of water to protein was the same after the run as it was in control rats. Metabolic measurements at rest and in the running wheel and weight loss in the 48-h run were used to estimate fuels used and water expended. Two-thirds of the initial amount of fat and 9% of the protein were metabolized. The terminal mean percentage of body fat was about twice that observed in rats trapped in the spring of 1967, when seed production was low: death in the 48-h run could not have been due to depletion of body fat alone. The powerful activity drive seen in hungary kangaroo rats presumably is intensified in dry years when food is scarce and may deplete their reserves enough to result in death from starvation.


2018 ◽  
Vol 7 ◽  
Author(s):  
Tabitha J. Hookey ◽  
Robert C. Backus ◽  
Allison M. Wara

AbstractMore than one-third of humans and companion dogs in Western societies are overweight or obese. In people, vitamin D deficiency is widespread and associated with obesity, a now recognised inflammatory state. Low vitamin D status occurs in dogs with inflammatory conditions, but its relationship with obesity has not been investigated. In otherwise healthy privately owned adult dogs of ideal body condition (control,n7) and dogs with overweight to obese body condition (treatment,n8), serum 25-hydroxyvitamin D (25(OH)D) concentration and body composition as inferred from2H-labelled water dilution space were evaluated. Subsequently, the dogs were transitioned to a commercial canine therapeutic weight-loss diet; control dogs were fed to maintain body weight and treatment dogs were energy-restricted to achieve a safe weight-loss rate. Thereafter, serum 25(OH)D concentration was re-evaluated 8 weeks after diet transition, and at the study end, which was 6 months or when ideal body condition was achieved. At study end, body composition analysis was repeated. Initial body condition scores and percentage body fat were positively correlated (ρ = 0·891;P< 0·001). However, percentage body fat and serum 25(OH)D concentration were not significantly correlated. Final serum 25(OH)D concentrations were greater (P< 0·05) than initial concentrations for control and treatment groups, indicating a diet but not weight-loss effect on vitamin D status. These findings suggest that vitamin D status of dogs is not affected by obesity or loss of body fat with therapeutic weight reduction.


2011 ◽  
Vol 21 (2) ◽  
pp. 97-104 ◽  
Author(s):  
Ina Garthe ◽  
Truls Raastad ◽  
Per Egil Refsnes ◽  
Anu Koivisto ◽  
Jorunn Sundgot-Borgen

When weight loss (WL) is necessary, athletes are advised to accomplish it gradually, at a rate of 0.5–1 kg/wk. However, it is possible that losing 0.5 kg/wk is better than 1 kg/wk in terms of preserving lean body mass (LBM) and performance. The aim of this study was to compare changes in body composition, strength, and power during a weekly body-weight (BW) loss of 0.7% slow reduction (SR) vs. 1.4% fast reduction (FR). We hypothesized that the faster WL regimen would result in more detrimental effects on both LBM and strength-related performance. Twenty-four athletes were randomized to SR (n = 13, 24 ± 3 yr, 71.9 ± 12.7 kg) or FR (n = 11, 22 ± 5 yr, 74.8 ± 11.7 kg). They followed energy-restricted diets promoting the predetermined weekly WL. All athletes included 4 resistance-training sessions/wk in their usual training regimen. The mean times spent in intervention for SR and FR were 8.5 ± 2.2 and 5.3 ± 0.9 wk, respectively (p < .001). BW, body composition (DEXA), 1-repetition-maximum (1RM) tests, 40-m sprint, and countermovement jump were measured before and after intervention. Energy intake was reduced by 19% ± 2% and 30% ± 4% in SR and FR, respectively (p = .003). BW and fat mass decreased in both SR and FR by 5.6% ± 0.8% and 5.5% ± 0.7% (0.7% ± 0.8% vs. 1.0% ± 0.4%/wk) and 31% ± 3% and 21 ± 4%, respectively. LBM increased in SR by 2.1% ± 0.4% (p < .001), whereas it was unchanged in FR (–0.2% ± 0.7%), with significant differences between groups (p < .01). In conclusion, data from this study suggest that athletes who want to gain LBM and increase 1RM strength during a WL period combined with strength training should aim for a weekly BW loss of 0.7%.


2009 ◽  
Vol 15 (3) ◽  
pp. 184-185

Measuring weight loss is important in determining if an exercise program works, but it is not the only objective. Losing body fat and maintaining a healthy body composition are more important. Body composition consists of lean tissue and fat. The body needs a certain amount of fat for essential functions (energy, regulating temperature). Karin Cottman, a certified personal trainer in Middleburg Heights, Ohio, keeps these ideas in mind when developing workout plans and diet goals for her clients.


2011 ◽  
Vol 165 (2) ◽  
pp. 243-248 ◽  
Author(s):  
Henna Cederberg ◽  
Ulla Rajala ◽  
Vesa-Matti Koivisto ◽  
Jari Jokelainen ◽  
Heljä-Marja Surcel ◽  
...  

ObjectiveGhrelin, a gut–brain peptide involved in energy homeostasis, circulates predominantly (>90%) in unacylated form. Previous studies, however, have focused on total and acylated ghrelin, and the role of unacylated ghrelin (UAG) is not well understood. Particularly, the association of UAG with weight loss and changes in body composition in adults remains unclear. We hypothesized that exercise-associated increase in UAG level is associated with weight loss, favorable changes in body composition, and body fat distribution.Design and methodsA prospective study of 552 young men (mean age 19.3 and range 19–28 years) undergoing military service with structured 6-month exercise training program. Exercise performance, body composition, and biochemical measurements were obtained at baseline and follow-up. Association between changes in UAG levels and body composition and body fat distribution were evaluated.ResultsAn increase in UAG level during the exercise intervention was associated with reduced weight, fat mass (FM), fat percentage (fat %), and waist circumference, but not with fat-free mass. Inverse associations of changes in UAG level with changes in waist circumference and fat % were independent of weight at baseline, and changes in weight and exercise performance. Associations of changes in UAG level with waist circumference were significantly stronger than with fat % after the adjustment for confounding variables.ConclusionUAG is associated with changes in body weight and body composition during an intensive long-term exercise intervention in young men. The association of UAG levels with changes in central obesity was stronger than with total FM.


Author(s):  
Constanza Mosso ◽  
Victoria Halabi ◽  
Tamara Ortiz ◽  
Maria Isabel Hodgson

AbstractThe aim of this study was to assess dietary intake, nutritional status, body composition, and physical activity level in a group of Chilean children and adolescents with Type 1 diabetes mellitus (T1DM), compare these parameters with the recommendations of the International Society for Pediatric and Adolescent Diabetes (ISPAD), and determine the relationships between dietary intake, body composition, and diabetes control.A total of 30 patients with T1DM (aged 15.2±4.0 years) were included. Dietary intake was assessed using a 92-item quantitative food frequency questionnaire. Body composition was determined using dual-energy X-ray densitometry. Physical activity was assessed by means of a survey.The energy intake of these patients was derived from 21.4% protein, 48% carbohydrates, and 31.2% fat. The glycosylated hemoglobin (HbA1c) was significantly correlated with fat as grams per day (r: 0.363, p<0.05) and calories per day (r: 0.364, p<0.05). The mean body fat percentage in females was 31.2% and 20.2% in males (p < 0.01) and the mean amount of physical activity was 4.5±2.7 h per week.The study patients had a higher protein intake than recommended by ISPAD. Dietary carbohydrate intake was rather low, and dietary fat intake was the same as the limits recommended by ISPAD. Diabetic control was significantly correlated with protein, carbohydrates, fat, and sodium intake. The girls in the study had a higher percentage of body fat than the standard recommendations for their age. The level of physical activity was adequate.


2021 ◽  
Vol 8 ◽  
Author(s):  
Chao-Jie He ◽  
Ye-Ping Fei ◽  
Chun-Yan Zhu ◽  
Ming Yao ◽  
Gang Qian ◽  
...  

Background and Aims: Weight-loss diets reduce body weight and improve blood pressure control in hypertensive patients. Intermittent energy restriction (IER) is an alternative to continuous energy restriction (CER) for weight reduction. We aimed to compare the effects of IER with those of CER on blood pressure control and weight loss in overweight and obese patients with hypertension during a 6-month period.Methods: Two hundred and five overweight or obese participants (BMI 28.7 kg/m2) with hypertension were randomized to IER (5:2 diet, a very-low-calorie diet for 2 days per week, 500 kcal/day for women and 600 kcal/day for men, along with 5 days of a habitual diet) compared to a moderate CER diet (1,000 kcal/day for women and 1,200 kcal/day for men) for 6 months. The primary outcomes of this study were changes in blood pressure and weight, and the secondary outcomes were changes in body composition, glycosylated hemoglobin A1c (HbA1c), and blood lipids.Results: Of the 205 randomized participants (118 women and 87 men; mean [SD] age, 50.2 [8.9] years; mean [SD] body mass index, 28.7 [2.6]; mean [SD] systolic blood pressure, 143 [10] mmHg; and mean [SD] diastolic blood pressure, 91 [9] mmHg), 173 completed the study. The intention-to-treat analysis demonstrated that IER and CER are equally effective for weight loss and blood pressure control: the mean (SEM) weight change with IER was −7.0 [0.6] kg vs. −6.8 [0.6] kg with CER, the mean (SEM) systolic blood pressure with IER was −7 [0.7] mmHg vs. −7 [0.6] mmHg with CER, and the mean (SEM) diastolic blood pressure with IER was −6 [0.5] mmHg vs. −5 [0.5] mmHg with CER, (diet by time P = 0.62, 0.39, and 0.41, respectively). There were favorable improvements in body composition, HbA1c, and blood lipid levels, with no differences between groups. Effects did not differ according to completer analysis. No severe hypoglycemia occurred in either group during the trial.Conclusions: Intermittent energy restriction is an effective alternative diet strategy for weight loss and blood pressure control and is comparable to CER in overweight and obese patients with hypertension.Clinical Trial Registration:http://www.chictr.org.cn, identifier: ChiCTR2000040468.


2020 ◽  
Author(s):  
Cristina Lugones-Sanchez ◽  
Maria Antonia Sanchez-Calavera ◽  
Irene Repiso-Gento ◽  
Esther G Adalia ◽  
J Ignacio Ramirez-Manent ◽  
...  

BACKGROUND Mobile health (mHealth) is currently among the supporting elements that may contribute to an improvement in health markers by helping people adopt healthier lifestyles. mHealth interventions have been widely reported to achieve greater weight loss than other approaches, but their effect on body composition remains unclear. OBJECTIVE This study aimed to assess the short-term (3 months) effectiveness of a mobile app and a smart band for losing weight and changing body composition in sedentary Spanish adults who are overweight or obese. METHODS A randomized controlled, multicenter clinical trial was conducted involving the participation of 440 subjects from primary care centers, with 231 subjects in the intervention group (IG; counselling with smartphone app and smart band) and 209 in the control group (CG; counselling only). Both groups were counselled about healthy diet and physical activity. For the 3-month intervention period, the IG was trained to use a smartphone app that involved self-monitoring and tailored feedback, as well as a smart band that recorded daily physical activity (Mi Band 2, Xiaomi). Body composition was measured using the InBody 230 bioimpedance device (InBody Co., Ltd), and physical activity was measured using the International Physical Activity Questionnaire. RESULTS The mHealth intervention produced a greater loss of body weight (–1.97 kg, 95% CI –2.39 to –1.54) relative to standard counselling at 3 months (–1.13 kg, 95% CI –1.56 to –0.69). Comparing groups, the IG achieved a weight loss of 0.84 kg more than the CG at 3 months. The IG showed a decrease in body fat mass (BFM; –1.84 kg, 95% CI –2.48 to –1.20), percentage of body fat (PBF; –1.22%, 95% CI –1.82% to 0.62%), and BMI (–0.77 kg/m<sup>2</sup>, 95% CI –0.96 to 0.57). No significant changes were observed in any of these parameters in men; among women, there was a significant decrease in BMI in the IG compared with the CG. When subjects were grouped according to baseline BMI, the overweight group experienced a change in BFM of –1.18 kg (95% CI –2.30 to –0.06) and BMI of –0.47 kg/m<sup>2</sup> (95% CI –0.80 to –0.13), whereas the obese group only experienced a change in BMI of –0.53 kg/m<sup>2</sup> (95% CI –0.86 to –0.19). When the data were analyzed according to physical activity, the moderate-vigorous physical activity group showed significant changes in BFM of –1.03 kg (95% CI –1.74 to –0.33), PBF of –0.76% (95% CI –1.32% to –0.20%), and BMI of –0.5 kg/m<sup>2</sup> (95% CI –0.83 to –0.19). CONCLUSIONS The results from this multicenter, randomized controlled clinical trial study show that compared with standard counselling alone, adding a self-reported app and a smart band obtained beneficial results in terms of weight loss and a reduction in BFM and PBF in female subjects with a BMI less than 30 kg/m<sup>2</sup> and a moderate-vigorous physical activity level. Nevertheless, further studies are needed to ensure that this profile benefits more than others from this intervention and to investigate modifications of this intervention to achieve a global effect. CLINICALTRIAL Clinicaltrials.gov NCT03175614; https://clinicaltrials.gov/ct2/show/NCT03175614. INTERNATIONAL REGISTERED REPORT RR2-10.1097/MD.0000000000009633


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