Obesity and overweight affect around 2 billion people worldwide. Despite the growing prevalence, the treatment of obesity is still an obscure field and the impacts of this disease on the clinical and public health perspective are urgent. Studies have demonstrated a fundamental role of the gut microbiota in the pathogenesis of obesity and discuss the impacts of diet and physical exercise on the microbiome profile. However, the mechanisms involved in these processes, referring to strategies such as intermittent fasting associated with physical training, are still poorly explored and understood. It is believed that intermittent fasting combined with physical exercise can promote a remodeling of the composition and function of the microbiota and that the present investigation is promising in the prevention and treatment of obesity.
Background: Obesity and overweight affect about 2 billion people worldwide. Despite the growing prevalence, the treatment of obesity is still an obscure field and the impacts of this disease on the clinical and public health perspective are urgent. Studies have demonstrated a fundamental role of the gut microbiota in the pathogenesis of obesity and discuss the impacts of diet and physical exercise on the microbiome profile. However, the mechanisms involved in these processes, referring to strategies such as intermittent fasting associated with physical training, are still poorly explored and understood. It is believed that intermittent fasting combined with physical exercise can promote a remodeling of the composition and function of the microbiota and that the present investigation is promising in the prevention and treatment of obesity. Methods: 60 obese women will participate in the study and will be randomly divided into 3 groups: 1) the intermittent fasting group, submitted to a diet for 8 weeks (n= 20); 2) the physical exercise group, submitted to physical training for 8 weeks (n= 20); and 3) intermittent fasting group associated with physical exercise, submitted to both interventions for 8 weeks (n= 20). All volunteers will perform collections and evaluations (pre and post intervention) of anthropometry, food consumption, indirect calorimetry to assess resting energy expenditure, body composition by BodPod®, blood collection for biochemical analysis and gene expression, collection of feces for the analysis of the intestinal microbiota and physical tests (Shuttle Walking Test, multiple repetition test and functional strength) for the exercise groups. Expected results: The synergistic effects of the proposed intervention are expected to improve gut microbiota and metabolic parameters in obese women.
Study Type
INTERVENTIONAL
Allocation
RANDOMIZED
Purpose
TREATMENT
Masking
NONE
Enrollment
60
Intervention with fasting protocol of alternate days 2 days a week and the other days with ad libitum consumption. Restricted food in 25% of the total daily needs on the days of the intermittent fasting protocol, with 18 hours of fasting and 6 hours of restricted feeding (18:6).
Intervention with high-intensity interval training, 3x per week, with intensity maintained between 70-85% of maximum heart rate.
University of São Paulo, School of Physical Education and Sports of Ribeirão Preto.
Ribeirão Preto, São Paulo, Brazil
Gabriela Batitucci
Ribeirão Preto, São Paulo, Brazil
Anthropometric changes (Body weight)
Changes in body weight (kilograms - Kg) pre and post intervention.
Time frame: eight weeks
Anthropometric - height assessment (meters)
Height measured in meters
Time frame: eight weeks
Anthropometric changes (BMI)
Changes in body mass index (evaluated through a calculation that combines weight measured in kilograms divided by height in meters squared - BMI in kg/m\^2) evaluated pre and post intervention.
Time frame: eight weeks
Anthropometric changes (Circumferences)
Changes in waist, abdominal, and hip circumferences (centimeters) evaluated pre and post intervention.
Time frame: eight weeks
Body composition changes
Changes in fat-free mass and fat mass evaluated pre and post intervention by whole-body air displacement plethysmography method, BodPod® .
Time frame: eight weeks
Dietary intake changes
Completion of the food record of three non-consecutive days, one day of the week that included the intermittent fasting protocol, another day of the week with ad libitum and a weekend day. This evaluation will take place pre-intervention, in the fourth week and after the intervention. Assessment of caloric intake, macronutrients and fiber evaluated pre and post intervention (Dietwin® software - São Paulo, Brazil).
Time frame: eight weeks
Indirect calorimetry assessment
Changes in resting metabolic rate (RMR) evaluated pre and post intervention by indirect calorimetry.
Time frame: eight weeks
Indirect calorimetry assessment (energetic substrates)
Changes in oxidation of substrates (lipids and carbohydrates) evaluated pre and post intervention by indirect calorimetry.
Time frame: eight weeks
Changes in total cholesterol and lipid fractions
Changes in total cholesterol, triglycerides, HDL-cholesterol and LDL-c evaluated pre and post intervention, quantified by Total Liquiform Cholesterol Kit, HDL Cholesterol Kit and Liquiform Triglycerides Kit, from Labtest diagnóstica®, using an enzymatic system and absorbance spectrophotometer.
Time frame: eight weeks
Changes in plasma cytokines
Changes in serum levels of cytokines IL-15, IL-10, TNF-α adiponectin, resistin, adipsin/Factor D, fetuin-A and C-reactive protein evaluated pre and post intervention, by MILLIPLEX® Kit.
Time frame: eight weeks
Changes in nitrogen balance
Determination of urinary nitrogen by chemiluminescence method. 24-hour urine analysis evaluated pre and post intervention. Calculation of nitrogen balance by a equation.
Time frame: eight weeks
Changes in concentration of short-chain fatty acids (acetate, propionate, and butyrate)
Quantification of short-chain fatty acids using stool samples, evaluated pre and post intervention, by gas chromatography method.
Time frame: eight weeks
Changes in gut microbiota_Extraction and DNA sequencing and library preparation.
Total fecal DNA extraction using the QIAamp 96 PowerFecal kit (Mobio-QIAGEN). Regions of interest V2-V3, V3-V4 and V4-V5 present in the extracted total DNA. Amplification and preparation of libraries according to the Illumina® kit protocol. 16S sequencing by Illumina® company's MiSeq platform. Metataxonomic analysis of 16S rDNA sequences by bioinformatics. Assessments analyzed pre and post intervention.
Time frame: eight weeks
Changes in aerobic performance
Physical tests performed pre and post intervention to assess aerobic physical fitness by incremental test adapted from Shuttle Walking.
Time frame: eight weeks
Changes in strength performance
Maximum dynamic muscular strength by test of multiple maximum repetitions (RM) in the leg press 45° and in the bench press.
Time frame: eight weeks
Changes in strength performance
Assessment of changes in maximal isometric muscle strength of the dorsal region and handgrip by dynamometry.
Time frame: eight weeks
Changes in strength performance
Strength endurance capacity by 1-minute functional tests (squat, free squat and push-up).
Time frame: eight weeks
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