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1.
Current opinion on dietary advice in order to preserve fat-free mass during a low-calorie diet.
Rondanelli, M, Faliva, MA, Gasparri, C, Peroni, G, Spadaccini, D, Maugeri, R, Nichetti, M, Infantino, V, Perna, S
Nutrition (Burbank, Los Angeles County, Calif.). 2020;:110667
Abstract
OBJECTIVES The loss of fat-free mass (FFM) that occurs during weight loss secondary to low-calorie diet can lead to numerous and deleterious consequences. We performed a review to evaluate the state of the art on metabolic and nutritional correlates of loss of fat free mass during low calorie diet and treatment for maintaining fat free mass. METHODS This review included 44 eligible studies. There are various diet strategies to maintain FFM during a low-calorie diet, including adoption of a very low carbohydrate ketogenic diet (VLCKD) and taking an adequate amount of specific nutrients (vitamin D, leucine, whey protein). RESULTS Regarding the numerous and various low-calorie diet proposals for achieving weight loss, the comparison of VLCKD with prudent low-calorie diet found that FFM was practically unaffected by VLCKD. There are numerous possible mechanisms for this, involving insulin and the insulin-like growth factor-1-growth hormone axis, which acts by stimulating protein synthesis. CONCLUSIONS Considering protein and amino acids intake, an adequate daily intake of leucine (4 g/d) and whey protein (20 g/d) is recommended. Regarding vitamin D, if the blood vitamin D has low values (<30 ng/mL), it is mandatory that adequate supplementation is provided, specifically calcifediol, because in the obese patient this form is recommended to avoid seizure in the adipose tissue; 3 to 4 drops/d or 20 to 30 drops/wk of calcifediol are generally adequate to restore normal 25(OH)D plasma levels in obese patients.
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Effects of high-intensity interval training on endothelial function, lipid profile, body composition and physical fitness in normal-weight and overweight-obese adolescents: A clinical trial.
da Silva, MR, Waclawovsky, G, Perin, L, Camboim, I, Eibel, B, Lehnen, AM
Physiology & behavior. 2020;:112728
Abstract
Endothelium-aggressive factors are associated with the development of atherosclerosis. Exercise training can either prevent or attenuate this process, but little is known about the effects of high-intensity interval training (HIIT) in adolescents. Thus, we assessed the effects of HIIT on endothelial function, lipid profile, body composition and physical fitness in normal-weight and overweight-obese adolescents. Thirty-eight participants aged 14-17 years who were physically inactive (IPAq) were divided in two groups: normal weight (NW, n = 13) and overweight-obese (OW, n = 25). Body composition, lipid profile, physical fitness and endothelial function (flow-mediated dilation, FMD) were assessed before and after undergoing the study protocol consisting of 12-week HIIT (∼15 min) + sport activities (30 min, 3×/week) + no diet. The differences were tested by GEE, Bonferroni post-hoc, p < 0.05. There were no changes in body composition after training period, but the OW group showed a reduction in waist (4.8 cm; p = 0.044) and abdominal circumference (3.7 cm; p = 0.049). We found improved physical fitness (cardiorespiratory endurance, explosive strength, abdominal muscle endurance and flexibility) in both groups. Lower endothelial function was found in the OW compared to NW (p = 0.042) at baseline. FMD increased (p < 0.001) in both groups from baseline (NW Δ4.1%; Cohen's effect size 0.64; OW Δ4.5%; Cohen's effect size 0.73) with no significant difference between the groups. In conclusion, a HIIT program even without any dietary changes can improve physical fitness and endothelial function among adolescents. These findings are clinically relevant because they support a reduction in endothelial damage that precedes the development of atherosclerosis.
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3.
Low-Frequency HIIT Improves Body Composition and Aerobic Capacity in Overweight Men.
Chin, EC, Yu, AP, Lai, CW, Fong, DY, Chan, DK, Wong, SH, Sun, F, Ngai, HH, Yung, PSH, Siu, PM
Medicine and science in sports and exercise. 2020;(1):56-66
Abstract
BACKGROUND The relationship between the frequency of high-intensity interval training (HIIT) and the resultant adaptations is largely unclear. PURPOSE This study compared the effects of different frequencies of HIIT with those of moderate-intensity continuous training (MICT) on body composition in overweight or obese adults. METHODS Fifty-six overweight or obese (body mass index = 26.4 ± 2.9) men between 18 and 30 yr old (age = 22.8 ± 3.1 yr) were randomly assigned to the following groups: no-intervention control (CON; n = 14), MICT performed thrice weekly (MICT×3/wk; n = 9), HIIT performed thrice weekly (HIIT×3/wk; n = 14), HIIT performed twice weekly (HIIT×2/wk; n = 10), and HIIT performed once weekly (HIIT×1/wk; n = 9). Each HIIT session consisted of 12 × 1-min bouts at 90% heart rate reserve, interspersed with 11 × 1-min bouts at 70% heart rate reserve. Aerobic capacity, body composition, resting heart rate, vascular function, insulin resistance, and biomarkers of metabolic syndrome risk factor were examined at baseline, after 4 wk, and after 8 wk of intervention. RESULTS Aerobic capacity and percent fat-free mass significantly increased in all exercise groups compared with those in the CON group (CON vs all exercise groups, P < 0.05), whereas body fat mass and systolic blood pressure significantly decreased after 8 wk of intervention in all exercise groups compared with those in the CON group (CON vs all exercise groups, P < 0.05). Body fat mass significantly decreased after 4 wk in all HIIT groups compared with those in the CON group (CON vs all HIIT groups, P < 0.05) but not in the MICT×3/wk group. CONCLUSION These novel results demonstrated that performing HIIT once weekly, even with a lower weekly volume of exercise, improved cardiorespiratory fitness, body composition, and blood pressure in overweight/obese adults. Low-frequency HIIT might be a feasible and effective strategy for the prescription of an initial exercise program for inactive, overweight, or obese young men.
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Effects of gradual weight loss v. rapid weight loss on body composition and RMR: a systematic review and meta-analysis.
Ashtary-Larky, D, Bagheri, R, Abbasnezhad, A, Tinsley, GM, Alipour, M, Wong, A
The British journal of nutrition. 2020;(11):1121-1132
Abstract
This systematic review and meta-analysis compared the effects of different rates of weight loss (WL), but equivalent total WL, on body composition and RMR. Studies examining gradual v. rapid WL on body composition and RMR in participants with overweight/obesity published up to October 2019 were identified through PubMed, the Cochrane Library, Web of Science, Embase, Scopus and Ovid databases. Meta-analysis was carried out using a fixed or random effects model as appropriate. Although the magnitude of WL was similar (mean difference 0·03 kg, 95 % CI –0·65, 0·71), gradual WL promoted greater reductions in fat mass (FM) (–1 kg, 95 % CI –1·70, –0·29) and body fat percentage (BFP) (–0·83 %, 95 % CI –1·49, –0·17). Gradual WL significantly preserved RMR compared with rapid WL (407·48 kJ, 95 % CI 76·76, 118·01). However, there was no significant difference in waist and hip circumferences, waist:hip ratio and fat-free mass (FFM) between gradual and rapid WL. The present systematic review and meta-analysis indicates beneficial effects of gradual WL, as compared with rapid WL, on FM, BFP and RMR in individuals with overweight/obesity. However, FFM changes and anthropometric indices did not significantly differ following different rates of WL.
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Review article: prognostic significance of body composition abnormalities in patients with cirrhosis.
Ebadi, M, Bhanji, RA, Tandon, P, Mazurak, V, Baracos, VE, Montano-Loza, AJ
Alimentary pharmacology & therapeutics. 2020;(4):600-618
Abstract
BACKGROUND Recent advances in evaluation of body composition show body mass index to be inadequate in differentiating between body compartments in cirrhosis. Given the limitations of body mass index, body composition evaluation using computed tomography has been increasingly used as a non-invasive clinical tool with prognostic value. Another factor influencing prognosis includes sex-specific differences in body composition that are seen in cirrhosis. AIM: To review current knowledge regarding the frequency and clinical implications of abnormal body composition features in cirrhosis. METHODS We searched PubMed database and limited the literature search to full-text papers published in English. Studies using inappropriate landmarks or demarcation of body composition components on computed tomography images were eliminated. RESULTS Sarcopenia is a well established factor affecting morbidity and mortality in cirrhosis. Other important body composition components that have been overlooked thus far include subcutaneous adipose tissue and visceral adipose tissue. Female patients with cirrhosis and low subcutaneous adiposity have a higher risk of mortality, whereas male patients with high visceral adiposity have a higher risk of hepatocellular carcinoma and recurrence following liver transplantation. Increased adipose tissue radiodensity has been associated with risk of decompensation and mortality. CONCLUSIONS Further evaluation of body composition abnormalities may help with development of targeted therapeutic strategies and improve outcome in patients with cirrhosis. Moreover, recognition of these abnormalities could improve prioritisation for liver transplantation as our current method based solely on liver function might lead to risk misclassification.
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6.
Body Composition in Adolescents and Young Adults with Anorexia Nervosa: A Clinical Review.
Tannir, H, Itani, L, Kreidieh, D, El Masri, D, Traboulsi, S, El Ghoch, M
Current rheumatology reviews. 2020;(2):92-98
Abstract
BACKGROUND Anorexia nervosa is a serious health condition characterized by a significant low body weight and alteration in body composition components. AIM: In the current paper, we aim to summarize the available literature concerning changes in body fat, lean, and bone masses, during anorexia nervosa and after complete weight restoration. METHODS Data were summarized using a narrative approach based on clinical expertise in the interpretation of the available evidence base in the literature. RESULTS The available data revealed three main findings. Firstly, anorexia nervosa causes a significant reduction in body fat mass, however it is completely restored after short-term weight normalization but with a central adiposity phenotype that does not seem to negatively influence treatment outcomes and appears to normalize after 1 year of normal weight maintenance. Secondly, anorexia nervosa causes a significant reduction in bone mineral density, but weight restoration is associated first (≈12 months) with stabilization of bone mineral density, followed by improvements (after ≈16 months); and finally, with complete normalization (after ≈30 months) after normal-weight maintenance. Thirdly, during anorexia nervosa loss of lean and skeletal body mass occurring in particular from the extremities rather than the central regions has been consistently reported, especially in patients with a Body Mass Index (BMI) ≤ 16.5 Kg/m2 however short-term weight restoration is associated with complete normalization. CONCLUSION Anorexia nervosa adversely affects body composition, however this medical complication seems to be reversible through the main treatment strategy of body weight restoration followed by normal weight maintenance, and this should be openly discussed with patients.
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The effects of dehydroepiandrosterone (DHEA) supplementation on body composition and blood pressure: A meta-analysis of randomized clinical trials.
Wang, F, He, Y, O Santos, H, Sathian, B, C Price, J, Diao, J
Steroids. 2020;:108710
Abstract
Dehydroepiandrosterone (DHEA) supplementation has been anecdotally considered as a tool to improve body composition and health status. We aimed to verify the impact of DHEA supplementation on traditional measurements of body composition and blood pressure (BP) due to their clinical applicability. A meta-analysis of randomized clinical trials was conducted based on the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) guidelines. Regarding anthropometric characteristics, DHEA supplementation did not change body weight (weighted mean difference (WMD): -0.16 kg, 95% CI: -1.02 to 0.70, p = 0.72) or body mass index (WMD: -0.18 kg/m2, 95% CI: -0.48 to 0.12, p = 0.24), but increased lean body mass (WMD: 0.45 kg, 95% CI: 0.15 to 0.75, p = 0.004) and decreased fat mass (WMD: -0.85%, 95% CI: -1.18 to -0.51, p = 0.000), when compared to control groups. Neither systolic (WMD: 0.98 mm Hg, 95% CI: -2.31 to 4.29, p = 0.56) nor diastolic BP were significantly changed (WMD: -1.62 mm Hg, 95% CI: -5.49 to 2.24, p = 0.49). Our findings demonstrate that DHEA supplementation increased lean body mass and decreased fat mass, but debate persists when translating the results into clinical benefit. Lastly, DHEA supplementation had a neutral effect on BP.
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BIOELECTRICAL VECTOR ANALYSIS IN OBESE ADOLESCENTS.
Oliveira Filho, JM, Bernardes, PS, Serpa, GHC, Siqueira, GDJ, Noll, M, Venâncio, PEM, Soares, V
Revista paulista de pediatria : orgao oficial da Sociedade de Pediatria de Sao Paulo. 2020;:e2019017
Abstract
OBJECTIVE To evaluate the hydration of obese and non-obese adolescents by vectorial bioimpedance analysis, in addition to verifying the associations between obesity and bioelectrical impedance vectorial analysis (BIVA) parameters. METHODS A cross-sectional study with adolescents between 14 and 18 years old (n=489, 300 boys and 189 girls). Electric bioimpedance (BIA; Quantum_II, RJL system, Rome, Italy) provided resistance and reactance parameters to calculate phase angle (PA), fat-free mass (FFM) and body fat (%BF). The confidence ellipses were compared, and the construction of the tolerance ellipses allowed individual and qualitative evaluation of the vectors and classification in dehydrated, normohydrated and hyperhydrated. RESULTS 78 obese and 411 eutrophic adolescents participated. Resistance (p<0.001) and reactance (p<0.001) and their normalization by stature (p<0.001) were reduced in the obese, whereas the PA was higher (p=0.003). %BF was 11.3% higher in obese adolescents. The main vector of the obese, both male (D=1.38; p<0.001) and female (D=1.49; p<0.001), indicated greater hydration. The ellipse of tolerance of the total sample showed that 25 (32.1%) were hyperhydrated and 02 (2.6%) vectors positioned in the sense of dehydration. A total of 17 (53.2%) girls and 16 (34.8%) boys were hyperhydrated. Logistic regression showed an inverse relation of BMI with resistance (p<0.001), reactance (p<0.001) and both normalized by stature. Adolescents with increased PA (p<0.001) were twice as likely to present obesity. CONCLUSIONS Obese adolescents were hyperhydrated and there was an inverse relationship of BMI with resistance and direct with PA.
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Dynamic Interactions Between LH and Testosterone in Healthy Community-Dwelling Men: Impact of Age and Body Composition.
Roelfsema, F, Liu, PY, Takahashi, PY, Yang, RJ, Veldhuis, JD
The Journal of clinical endocrinology and metabolism. 2020;(3):e628-41
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Abstract
BACKGROUND Aging is associated with diminished testosterone (Te) secretion, which may be attributed to Leydig cell dysfunction, decreased pituitary stimulation, and altered Te feedback. OBJECTIVE To study all regulatory nodes-gonadotropin-releasing hormone (GnRH), luteinizing hormone (LH) and Leydig cell-in the same cohort of healthy men. STUDY DESIGN This was a placebo-controlled, blinded, prospectively randomized cross-over study in 40 men, age range 19 to 73 years, and body mass index (BMI) range 20 to 34.3 kg/m2. A submaximal dose of the GnRH antagonist ganirelix was used to assess outflow of GnRH, by calculating the difference between LH output during the control arm and ganirelix arm. Ketoconazole (a steroidogenic inhibitor) was used to estimate feedback, by the difference in LH output during the ketoconazole and control arm. High-dose ganirelix and repeated LH infusions were used to measure testicular responsivity. Blood sampling was performed at 10-minute intervals. RESULTS There were age-related, but not body composition-related decreases in estimated GnRH secretion, the feedback strength of Te on LH, and Leydig cell responsivity to LH, accompanied by changes in approximate entropy. Bioavailable Te levels were negatively related to both age and computed tomography (CT)-estimated abdominal visceral mass (AVF), without interaction between these variables. The LH response to a submaximal dose of GnRH was independent of age and AVF. CONCLUSION Advancing age is associated with (1) attenuated bioavailable Te secretion caused by diminished GnRH outflow and not by decreased GnRH responsivity of the gonadotrope, (2) diminished testicular responsivity to infused LH pulses, and (3) partial compensation by diminished Te feedback on central gonadotropic regulation.
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Resistance Training Improves a Cellular Health Parameter in Obese Older Women: A Randomized Controlled Trial.
Ribeiro, AS, Schoenfeld, BJ, Dos Santos, L, Nunes, JP, Tomeleri, CM, Cunha, PM, Sardinha, LB, Cyrino, ES
Journal of strength and conditioning research. 2020;(10):2996-3002
Abstract
Ribeiro, AS, Schoenfeld, BJ, dos Santos, L, Nunes, JP, Tomeleri, CM, Cunha, PM, Sardinha, LB, and Cyrino, ES. Resistance training improves a cellular health parameter in obese older women: a randomized controlled trial. J Strength Cond Res 34(10): 2996-3002, 2020-Phase angle (PhA) is a viable indicator of cellular health, with higher values reflecting better cellularity, cell membrane integrity, and cell function. Adaptive responses to resistance training (RT) on PhA may be important in obese older people. The main purpose of the present study was to investigate the effects of 8 weeks of RT on PhA in obese older women. Thirty-three obese older women (68.1 ± 5.7 years, 71.6 ± 10.1 kg, 154.5 ± 6.7 cm, 30.0 ± 4.1 kg·m, and 45.0 ± 6.0% body fat) were randomly allocated into 1 of 2 groups: a training group that performed the RT program (TG, n = 18) or a nonexercise control group (CG, n = 15). The whole-body RT consisted of an 8-week RT program involving 8 exercises performed for 3 sets of 8-12 repetitions 3 times a week. Anthropometric, body fat and fat-free mass, PhA, total body water (TBW), intracellular water (ICW), and extracellular water compartments were performed at before and after training. After the intervention period, the TG presented greater increases (p < 0.05) than CG for fat-free mass (TG = +1.3% and CG = -0.3%), TBW (TG = +2.0% and CG = -1.7%), ICW (TG = +3.1% and CG = -1.9%), and PhA (TG = +3.4% and CG = -1.4%), and lower values for percentage of body fat (TG = -1.3% and CG = +0.9%) and bioimpedance resistance (TG = -4.6% and CG = +2.3%). Our results suggest that 8 weeks of RT improves PhA-a cellular health parameter-in obese older women.