scholarly journals Time-restricted eating effects on performance, immune function, and body composition in elite cyclists: a randomized controlled trial

Author(s):  
Tatiana Moro ◽  
Grant Tinsley ◽  
Giovanni Longo ◽  
Davide Grigoletto ◽  
Antonino Bianco ◽  
...  

Abstract Background Although there is substantial interest in intermittent fasting as a dietary approach in active individuals, information regarding its effects in elite endurance athletes is currently unavailable. The present parallel randomized trial investigated the effects of a particular intermittent fasting approach, called time-restricted eating (TRE), during 4 weeks of high-level endurance training. Methods Sixteen elite under-23 cyclists were randomly assigned either to a TRE group or a control group (ND). The TRE group consumed 100% of its estimated daily energy needs in an 8-h time window (from 10:00 a.m. to 6:00 p.m.) whilst energy intake in the ND group was distributed in 3 meals consumed between 7:00 a.m. and 9:00 p.m. Fat and fat-free mass were estimated by bioelectrical impedance analysis and VO2max and basal metabolism by indirect gas analyzer. In addition, blood counts, anabolic hormones (i.e. free testosterone, IGF-1) and inflammatory markers (i.e. IL-6, TNF-α) were assessed. Results TRE reduced body weight (− 2%; p = 0.04) and fat mass percentage (− 1.1%; p = 0.01) with no change in fat-free mass. Performance tests showed no significant differences between groups, however the peak power output/body weight ratio (PPO/BW) improved in TRE group due to weight loss (p = 0.02). Free testosterone and IGF-1 decreased significantly (p = 0.01 and p = 0.03 respectively) in TRE group. Leucocyte count decreased in ND group (p = 0.02) whilst the neutrophils-to-lymphocytes ratio (NLR) decreased significantly (p = 0.03) in TRE group. Conclusions Our results suggest that a TRE program with an 8-h feeding window elicits weight loss, improves body composition and increases PPO/BW in elite cyclists. TRE could also be beneficial for reducing inflammation and may have a protective effect on some components of the immune system. Overall, TRE could be considered as a component of a periodized nutrition plan in endurance athletes. Trial registration This trial was retrospectively registered at clinicaltrials.gov as NCT04320784 on 25 March 2020.

2021 ◽  
pp. 152-161
Author(s):  
A. Yu. Vаshura

Weight, BMI and its changes with age are one of the key indicators in pediatrics. The values of these indicators are the main parameters for assessing nutritional status (NS) and defining nutritional disorders - obesity and protein-energy malnutrition. At the same time, body weight and its changes only conditionally reflect the mass of fat and the amount of fat-free mass (especially the compartment of skeletal muscles). In the healthy population (in which the relevant references had been obtained), the changes of BMI can significantly reflect the changes of body composition. In children with chronic diseases (and/or with metabolic disorders, and/ or in oncopediatrics) the sensitivity of BMI as an indicator of NS is significantly lower and variable. This is due to deviations from the “normal” body composition existing in these patients. As a result, a deficit of fat-free mass can be accompanied by an excess of fat mass. Sarcopenia, which has negative consequences for the child, can be masked by obesity. Therefore, this condition, sar-copenic obesity, represents a huge problem. On the one hand, due to the coexistence of two nutritional disorders in one patient. On the other hand, due to underestimation in pediatrics. The latter is the consequence of frequent understanding of the child’s body weight as an unconditional and independent indicator. This can have dramatic consequences for the development and growth of the child. Therefore, weight loss in an obese child does not yet mean positive dynamics.


2020 ◽  
Author(s):  
Majid Mohammadshahi ◽  
Elahe Zakizadeh ◽  
Kambiz Ahmadi Angali ◽  
Majid Ravanbakhsh ◽  
Bijan Helli

Abstract Background: The anti-obesity effects of Alpha-lipoic acid (α-LA) and isotonic contraction has been reported. However, the underlying mechanism is not fully understood. This study aimed to investigate the effect of α-LA supplementation and Faradic (an electrical stimulating system) on anthropometric parameters, body composition, VEGF, Sirtunin-1, nitric oxide (NO), and PGC1-α in obese people undergoing a weight loss regime.Methods: This randomized clinical trial was carried out on 100 obese adults. The subjects were randomly assigned to four groups of 25 subjects including Faradic, α-LA, -α-LA+Faradic, and control. A Bio Impedance Analyzer (BIA) was used to estimate anthropometric measurements including weight, body mass index (BMI), fat mass, and fat free mass. The serum levels of Sirtunin-1, PGC1-α, VEGF, and NO levels were measured. All measurements were done at baseline and after 8 weeks of intervention.Results: A significant weight reduction was observed in all four groups compared to baseline (p=<0.01). The placebo group had significantly higher weight, BMI, weight circumstance (WC), and body fat (BF) compared with the other groups. The α-LA+Faradic group had significantly lower weight, BMI, BF, WC than control, faradic, and α-LA groups and higher, Sitruin,, and PGC than the control group (all P <0.05).Conclusions: The findings indicated that the α-LA and Faradic interventions may have a synergistic effect on weight, BMI, BF, WC, and SLM, possibly through changes in serum level of VEGF, NO, and PGC. Further researches are warranted to clarify the mutual effects of –α-LA and Faradic on obesity and molecular biomarkers.Name of the registry: Iranian Registry of Clinical TrialsTrial registration number: IRCT20131117015424N2Date of registration: https://www.irct.ir/search/result?query=IRCT20131117015424N2URL of trial registry record: 04/04/2018


2021 ◽  
Author(s):  
Jeanette Reffstrup Christensen ◽  
Camilla Sortsø ◽  
Jørgen T Lauridsen ◽  
Pernille R Jakobsen ◽  
Ditte H Laursen ◽  
...  

BACKGROUND Lifestyle interventions can delay and reverse the onset of type 2 diabetes (T2D) and decrease morbidity and mortality. Studies suggest that digital coaching based on real-time monitoring can lead to clinically relevant weight loss, as well as decreased or normalized hemoglobin A1c (HbA1c) for a significant number of patients. OBJECTIVE To assess whether an eHealth lifestyle coaching program (LIVA 2.0) for patients with T2D who are motivated for lifestyle changes leads to significant weight loss and decreased HbA1c, compared to usual care. METHODS In a randomized controlled single-blinded trial, 170 patients with T2D were enrolled from March 2018 to March 2019 and randomized to the intervention (100) and control (70) groups. Patients were recruited via their general practitioners, the Danish diabetes organization, and social media. The intervention comprised an initial face-to-face motivational interview followed by digital coaching. The same healthcare professional coach provided synchronous and asynchronous multimodal feedback and used digital behavioral change techniques enabled by an app providing live monitoring of lifestyle behaviors. Primary outcome was body weight. Secondary outcomes were changes in HbA1c, body composition, lipids, and quality of life at 6 months. RESULTS At 6 months, 75 patients (75%) in the intervention group and 53 patients (76%) in the control group remained in the study. Mean body weight loss was 4.2 kg (95% CI, 5.5- 3.0) in the intervention group vs 1.5 kg (95% CI, 2.57- 0.48) in the control group (P = .005). In the intervention group, 36 (52%) patients lost > 3% body weight, compared to 12 (32%) patients in the control group. Mean HbA1c was lower in both groups at 6 months, with reductions of 8.2% (95% CI, 11.01 to 5.29) and 5.5% (95% CI, 8.75 to 2.76) for the intervention and control groups, respectively (P = .203). In the intervention group, 24 (32%) had an HbA1c <6.5% at 6 months, compared to 8 (15%) in the control group (P = .03). CONCLUSIONS Reduction in body weight and remission rate for HbA1c, as well as improved body composition can be enhanced by using digital lifestyle coaching for patients with T2D. CLINICALTRIAL Trial Registration: Clinicaltrials.gov NCT03788915 https://clinicaltrials.gov/ct2/show/NCT03788915 International Registered Report Identifier (IRRID): DERR2-10.2196/19172 INTERNATIONAL REGISTERED REPORT RR2-10.2196/19172


2020 ◽  
Vol 66 (2) ◽  
pp. 222-226
Author(s):  
Carlos Henrique Ribeiro Lima ◽  
Iara Katrynne Fonsêca Oliveira ◽  
Karoline de Macêdo Gonçalves Frota ◽  
Cecilia Maria Resende Gonçalves de Carvalho ◽  
Adriana de Azevedo Paiva ◽  
...  

SUMMARY OBJECTIVE To verify the relationship of intermittent fasting in the bodyweight of overweight and obese individuals through a systematic literature review. METHODS This is a systematic review based on randomized controlled trials. The articles were consulted in the databases: Science Direct, PubMed e BVS. This review was evaluated through the PRISMA recommendation. RESULTS After the selection process, four articles were included in this review, comparing intermittent fasting (IF) with calorie restriction diet (CRD) as a control group. In 2 studies using similar protocols, there was no significant reduction in body weight of overweight or obese subjects. In the other two studies using different protocols, weight loss was significant in the IF group compared to the CRD group. CONCLUSIONS Results did not provide evidence of the effect of intermittent fasting on weight loss in overweight or obese individuals.


2021 ◽  
Vol 7 ◽  
Author(s):  
Joana M. Correia ◽  
Inês Santos ◽  
Pedro Pezarat-Correia ◽  
Analiza M. Silva ◽  
Goncalo V. Mendonca

Intermittent fasting (IF) has gained popularity for body-composition improvement purposes. The aim of this systematic review and meta-analysis was to summarize the effects of Ramadan vs. non-Ramadan IF on parameters of body composition. We conducted a comprehensive search of peer-reviewed articles in three electronic databases: PubMed, Scopus, and Web of Science (published until May 2020). Studies were selected if they included samples of adults (≥18 years), had an experimental or observational design, investigated any type of IF and included body composition outcomes. Meta-analytical procedures were conducted when feasible. Sixty-six articles met the eligibility criteria. We found that non-Ramadan IF is effective for decreasing body weight (−0.341 (95% CI [−0.584, −0.098], p = 0.006), body mass index (−0.699, 95% CI [−1.05, −0.347], p &lt; 0.001), and absolute fat mass (−0.447, 95% CI [−0.673, −0.221], p &lt; 0.001). When contrasting pre- post-intervention data on fat-free mass between treatments and controls, group-differences were non-significant (p &gt; 0.05). Conversely, we observed a significant increase in fat-free mass when comparing pre- to post-intervention in a within design fashion (0.306, 95% CI [0.133, 0.48], p = 0.001). Finally, despite being accompanied by dehydration, Ramadan IF is effective in decreasing body weight (−0.353; 95% CI [−0.651, −0.054], p = 0.02) and relative fat mass (−0.533; 95% CI [−1.025, −0.04], p = 0.034). Ramadan IF seems to implicate some beneficial adaptations in weight management, although non-Ramadan IF appears to be more effective in improving overall body composition.


Life ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 74
Author(s):  
Kuno Hottenrott ◽  
Tanja Werner ◽  
Laura Hottenrott ◽  
Till P. Meyer ◽  
Jürgen Vormann

Background: Intermittent fasting (IF) combined with exercise has been suggested to enhance weight loss. However, both procedures might negatively influence acid–base status. The aim of this study was to determine the combined effects of IF, exercise training and alkaline supplementation in overweight subjects on body composition and running performance. Methods: 80 overweight subjects of age 45.5 ± 7.8 years were assigned to IF or non-intermittent fasting (nIF). Furthermore, subjects were randomly assigned to take either an alkaline supplement (IF-v, nIF-v) or a placebo (IF-p, nIF-p) twice a day. All subjects performed a personalized endurance exercise program (3–4 times/week for 12 weeks). Body weight, body composition, running performance and acid–base parameters were determined before (pre) and after the 12-week program (post). Results: 68 participants completed the study. There was a significant effect on body weight loss, body fat loss, visceral fat loss and running performance enhancement in all groups (p < 0.01) for pre and post measurements. Body weight decreased in all groups (IF-p: −5.80 ± 0.77 kg and nIF-p: −3.40 ± 0.58 kg; IF-v: −8.28 ± 0.75 kg and nIF-v: −5.59 ± 0.87 kg). In both dietary strategies, weight loss was significantly further enhanced by alkaline supplementation. The increase in running velocity was significantly higher in IF combined with alkaline supplementation (IF-v 1.73 ± 0.23 km/h and IF-p 0.97 ± 0.20 km/h). In addition, alkaline supplementation increased plasma HCO3− concentration and urinary pH. Conclusion: Exercise training in combination with IF and alkaline supplementation is an effective strategy to reduce body weight and improve running performance in a 12-week intervention.


Obesity Facts ◽  
2021 ◽  
Vol 14 (2) ◽  
pp. 222-245
Author(s):  
Giovanna Muscogiuri ◽  
Marwan El Ghoch ◽  
Annamaria Colao ◽  
Maria Hassapidou ◽  
Volkan Yumuk ◽  
...  

<b><i>Background:</i></b> The very low-calorie ketogenic diet (VLCKD) has been recently proposed as an appealing nutritional strategy for obesity management. The VLCKD is characterized by a low carbohydrate content (&#x3c;50 g/day), 1–1.5 g of protein/kg of ideal body weight, 15–30 g of fat/day, and a daily intake of about 500–800 calories. <b><i>Objectives:</i></b> The aim of the current document is to suggest a common protocol for VLCKD and to summarize the existing literature on its efficacy in weight management and weight-related comorbidities, as well as the possible side effects. <b><i>Methods:</i></b> This document has been prepared in adherence with Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) guidelines. Literature searches, study selection, methodology development, and quality appraisal were performed independently by 2 authors and the data were collated by means of a meta-analysis and narrative synthesis. <b><i>Results:</i></b> Of the 645 articles retrieved, 15 studies met the inclusion criteria and were reviewed, revealing 4 main findings. First, the VLCKD was shown to result in a significant weight loss in the short, intermediate, and long terms and improvement in body composition parameters as well as glycemic and lipid profiles. Second, when compared with other weight loss interventions of the same duration, the VLCKD showed a major effect on reduction of body weight, fat mass, waist circumference, total cholesterol and triglyceridemia as well as improved insulin resistance. Third, although the VLCKD also resulted in a significant reduction of glycemia, HbA1c, and LDL cholesterol, these changes were similar to those obtained with other weight loss interventions. Finally, the VLCKD can be considered a safe nutritional approach under a health professional’s supervision since the most common side effects are usually clinically mild and easily to manage and recovery is often spontaneous. <b><i>Conclusions:</i></b> The VLCKD can be recommended as an effective dietary treatment for individuals with obesity after considering potential contra-indications and keeping in mind that any dietary treatment has to be personalized. <b><i>Prospero Registry:</i></b> The assessment of the efficacy of VLCKD on body weight, body composition, glycemic and lipid parameters in overweight and obese subjects: a meta-analysis (CRD42020205189).


2021 ◽  
Author(s):  
Thiago Ramos de Barros ◽  
Verônica Pinto Salerno ◽  
Thalita Ponce ◽  
Míriam Raquel Meira Mainenti

ABSTRACT Introduction To train and prepare cadets for a career as firefighters in Rio de Janeiro, the second-year students of the Officers Training Course are submitted to a Search, Rescue, and Survival Training (SRST) course, which is characterized by long periods of high physical exertion and sleep restriction during a 9-day instruction module, and food restriction during a 7-day survival module. The present study investigated changes in the body composition of 39 male cadets submitted to SRST during training and 4 weeks of recovery with no restrictions in food consumption. Materials and Methods Each cadet was evaluated by anthropometric measurements at six time points: pre-SRST; after the first module; after the second module; and after 1, 2, and 4 weeks of recovery. Measurements included body girths and skinfolds, to estimate trunk (chest and waist) and limbs (arm and thigh) dimensions, as well as body composition. Repeated measures ANOVA and Friedman test were applied (depending on each data distribution). Results Statistically significant decreases in body weight (76.2; 69.8-87.2 to 63.9; 58.9-73.5 kg) and fat free mass (FFM, 69.2; 63.7-77.2 to 60.1; 56.2-68.0 kg) were observed following the second module of SRST. Following a single week of recovery, the FFM returned to pre-SRST values. Body weight returned to pre-training levels in 2 weeks. Body fat percentage and mass also significantly decreased during SRST (9.0; 7.7-12.3 to 6.5; 5.1-9.3% and 6.9; 5.6-10.0 to 6.9; 5.6-10.0 kg, respectively), which showed a slower and more gradual recovery that reached pre-SRST values after 4 weeks. The girths of arm, thigh, chest and waist significantly decreased due to SRST. The girths of the limbs (arm and thigh) returned to pre-training values after one month of recovery, while the girths of the trunk (chest and waist) did not return to pre-SRST values during the study period. Conclusions The findings suggest that men who experience periods of high energy demands and sleep restriction followed by a period of food restriction will endure unavoidable physical consequences that can be mostly reversed by a 1-month recovery.


2019 ◽  
Vol 3 (Supplement_1) ◽  
Author(s):  
Shih Lung Woo ◽  
Dina Ben-Nissan ◽  
Zahra Ezzat-Zadeh ◽  
Jieping Yang ◽  
Lijun Zhang ◽  
...  

Abstract Objectives This study was designed to assess the effects of mixed nut consumption on body weight and composition, and gut microbiome in obese individuals. Primary outcome was change in body weight and composition. Secondary outcomes include gut microbiome composition, inflammatory markers, and plasma lipids. Methods The reported results are from an interim analysis (n = 50) of a randomized, placebo controlled, parallel study. Total enrollment target is 154 overweight/obese subjects (BMI 27–35 kg/m2). Participants were randomly assigned to consume either 1.5oz mixed tree nuts or pretzels with equal calorie content daily for 24 weeks. The study included a 12-week weight loss phase (500 kcal per day less than total daily energy expenditure), followed by a 12-week weight maintenance phase. Body composition, fasting blood, and stool samples were collected at baseline, week 12 and 24. Body composition, and vitals were analyzed, whereas plasma lipid profile, fecal microbiome, and microbiome metabolites analysis is still pending. Results At week 12, subjects from both the pretzel (n = 15, 10 dropouts; P = 0.009) and nut group (n = 22, 3 dropouts; P = 0.038) lost significant amount of weight. The trend of weight changes did not differ between groups (P = 0.530). Subjects from both groups were able to sustain weight loss through 24 weeks (pretzel: 81.43 ± 3.85 kg at baseline vs. 79.43 ± 4.08 kg at week 24, P = 0.028; nut: 84.26 ± 3.78 kg at baseline vs. 82.38 ± 3.72 kg at week 24, P = 0.026). At week 12, fat mass in both groups was significantly decreased (pretzel: P = 0.002; nut: P = 0.012). The trend of fat changes did not differ between groups (P = 0.547). Subjects from both groups were able to sustain fat loss through 24 weeks (pretzel: 30.84 ± 1.75 kg at baseline vs. 29.25 ± 2.12 kg at week 24, P = 0.024; nut: 31.51 ± 1.56 kg vs 30.21 ± 1.81 kg at week 24, P = 0.04). Muscle mass, and blood pressure were not significantly different between both groups. Conclusions Our data suggested that tree nuts could be consumed as part of a healthy weight loss meal plan without concern of causing weight gain. Further analysis of the remaining samples is needed to confirm results. Due to higher dropouts in the pretzel group, future intention-to-treat analysis is also needed to eliminate bias. Funding Sources This study is supported by the International Tree Nut Council.


2016 ◽  
Vol 41 (6) ◽  
pp. 611-617 ◽  
Author(s):  
Jameason D. Cameron ◽  
Ronald J. Sigal ◽  
Glen P. Kenny ◽  
Angela S. Alberga ◽  
Denis Prud’homme ◽  
...  

There has been renewed interest in examining the relationship between specific components of energy expenditure and the overall influence on energy intake (EI). The purpose of this cross-sectional analysis was to determine the strongest metabolic and anthropometric predictors of EI. It was hypothesized that resting metabolic rate (RMR) and skeletal muscle mass would be the strongest predictors of EI in a sample of overweight and obese adolescents. 304 post-pubertal adolescents (91 boys, 213 girls) aged 16.1 (±1.4) years with body mass index at or above the 95th percentile for age and sex OR at or above the 85th percentile plus an additional diabetes risk factor were measured for body weight, RMR (kcal/day) by indirect calorimetry, body composition by magnetic resonance imaging (fat free mass (FFM), skeletal muscle mass, fat mass (FM), and percentage body fat), and EI (kcal/day) using 3 day food records. Body weight, RMR, FFM, skeletal muscle mass, and FM were all significantly correlated with EI (p < 0.005). After adjusting the model for age, sex, height, and physical activity, only FFM (β = 21.9, p = 0.007) and skeletal muscle mass (β = 25.8, p = 0.02) remained as significant predictors of EI. FFM and skeletal muscle mass also predicted dietary protein and fat intake (p < 0.05), but not carbohydrate intake. In conclusion, with skeletal muscle mass being the best predictor of EI, our results support the hypothesis that the magnitude of the body’s lean tissue is related to absolute levels of EI in a sample of inactive adolescents with obesity.


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