Effects of Time-restricted Eating and Aerobic Exercise Training in Women With Overweight and Obesity

Effects of Time-restricted Eating Combined With Aerobic Exercise Training on Body Composition and Cardiometabolic Parameters in Women With Overweight and Obesity: a Randomized Clinical Trial

Time-restricted eating (TRE) is a dietary approach that aims to increase fasting time and decrease the eating window. Promising TRE effects on weight loss and improvements in some cardiometabolic risk factors have been reported in studies in animals and humans. However, the impacts of TRE combined with aerobic exercise training in individuals with overweight and obesity have been insufficiently investigated.

Additionally, aerobic training performed in a fasted state appears to promote physiological adaptations that may improve the metabolic health in individuals with overweight and obesity.

The present study investigates the effects of 8 weeks of TRE associated with aerobic training in a fasted state versus a fed state on body composition and cardiometabolic parameters in women with overweight and grade 1 obesity.

Study Overview

• Status: Not yet recruiting
• Conditions: Obesity; Overweight and Obesity; Time Restricted Feeding; Intermittent Fasting; Time Restricted Eating
• Intervention / Treatment: Behavioral: Dietary and Exercise Approaches; Behavioral: Dietary and Exercise Approaches; Behavioral: Dietary Approach

• Study Type: Interventional
• Enrollment (Estimated): 30
• Phase: Not Applicable

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Female;
• Body mass index (BMI) between 25 and 34.9 kg/m²;
• Age between 20 and 40 years;
• Not engaged in any structured exercise program;
• Weight stable for ~3 months before the beginning of the study;
• Able to give written informed consent.

Exclusion Criteria:

• Current smoker;
• Habitual drinkers (>1 serving/day) of alcoholic beverages;
• Cardiometabolic diseases (dyslipidemia, diabetes, hypertension, etc);
• Current treatment with medication or supplements which significantly affect the main studied variables;
• Bariatric surgery;
• Night-shift workers;
• Strict vegetarian/vegan;
• Pregnancy, planned pregnancy (within the study period), lactating;
• Postmenopausal women;
• Self-reported menstrual cycle irregularities;
• Habitual fasting window >16 hours;
• Concomitant participation in other studies.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Time-Restricted Eating and Aerobic Exercise Performed in Fasted State; Participants will be prescribed a diet plan to promote weight loss, but no food will be provided to them. Diets will be formulated to contain 50% energy as carbohydrate, 20% as protein, and 30 % as fat. Participants will be instructed to divide their daily energy intake between three meals each day (lunch, afternoon snack, and dinner). Participants will be instructed to eat from 12.00 until 20.00 (8-hour window). Aerobic exercise sessions will be carried out during the morning shift with participants in a fasted state.	Behavioral: Dietary and Exercise Approaches; Intermittent fasting plus energy restriction combined with aerobic exercise performed in a fasted state.; Behavioral: Dietary and Exercise Approaches; Intermittent fasting plus energy restriction combined with aerobic exercise performed in a fed state.
Active Comparator: Time-Restricted Eating and Aerobic Exercise Performed in Fed State; Participants will be prescribed a diet plan to promote weight loss, but no food will be provided to them. Diets will be formulated to contain 50% energy as carbohydrate, 20% as protein, and 30 % as fat. Participants will be instructed to divide their daily energy intake between three meals each day (lunch, afternoon snack, and dinner). Participants will be instructed to eat from 12.00 until 20.00 (8-hour window). Aerobic exercise sessions will be carried out during the afternoon shift with participants in a fed state.	Behavioral: Dietary and Exercise Approaches; Intermittent fasting plus energy restriction combined with aerobic exercise performed in a fasted state.; Behavioral: Dietary and Exercise Approaches; Intermittent fasting plus energy restriction combined with aerobic exercise performed in a fed state.
Other: Time-Restricted Eating; Participants will be prescribed a diet plan to promote weight loss, but no food will be provided to them. Diets will be formulated to contain 50% energy as carbohydrate, 20% as protein, and 30 % as fat. Participants will be instructed to divide their daily energy intake between three meals each day (lunch, afternoon snack, and dinner). Participants will be instructed to eat from 12.00 until 20.00 (8-hour window). Participants in this arm will not perform aerobic exercise training.	Behavioral: Dietary Approach; Intermittent fasting plus energy restriction without aerobic exercise training.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Insulin sensitivity (indices)	Including but not limited to the Sensitivity Matsuda index	Change from baseline. Measured at baseline and after 8 weeks.

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Insulin resistance (indices)	Including but not limited to Homeostatic Model Assessment for Insulin Resistance (HOMA-IR).	Change from baseline. Measured at baseline and after 8 weeks.
Fasting insulin levels (µIU/mL)	Measured by enzyme-Linked Immunosorbent Assay	Change from baseline. Measured at baseline and after 8 weeks.
Fasting glucose levels (mg/dL)	Measured by colorimetric method	Change from baseline. Measured at baseline and after 8 weeks.
Fat Mass (kg)	Measured by Dual-energy X-ray Absorptiometry under fasting condition.	Change from baseline. Measured at baseline and after 8 weeks.
Fat Percentage (%)	Measured by Dual-energy X-ray Absorptiometry under fasting condition.	Change from baseline. Measured at baseline and after 8 weeks.
Fat Free Mass (kg)	Measured by Dual-energy X-ray Absorptiometry under fasting condition.	Change from baseline. Measured at baseline and after 8 weeks.
Body Weight (kg)	Measured by Dual-energy X-ray Absorptiometry under fasting condition.	Change from baseline. Measured at baseline and after 8 weeks.
Body Weight (kg)	Measured on a digital scale.	Change from baseline. Measured at baseline and after 4, and 8 weeks.
Bone Mineral Content (kg)	Measured by Dual-energy X-ray Absorptiometry under fasting condition.	Change from baseline. Measured at baseline and after 8 weeks.
Body Mass Index (kg/m^2)	Calculated from weight in kilograms divided by height in meters squared.	Change from baseline. Measured at baseline and after 8 weeks.
Fasting ketones (β-hydroxybutyrate) levels (mmol/L)		Change from baseline. Measured at baseline and after 8 weeks.
Resting metabolic rate (Kcal/day)	Measured by indirect calorimetry under resting and fasting conditions.	Change from baseline. Measured at baseline and after 8 weeks.
Substrate Oxidation (respiratory exchange ratio)	Measured by indirect calorimetry under resting and fasting conditions.	Change from baseline. Measured at baseline and after 8 weeks.
Glucose tolerance	Measured by oral glucose tolerance test (2-h OGTT)	Change from baseline. Measured at baseline and after 8 weeks.
Fasting lipid profile levels	Measured by colorimetric method	Change from baseline. Measured at baseline and after 8 weeks.
β cell function (indices)	Including but not limited to HOMA-β	Change from baseline. Measured at baseline and after 8 weeks.
Absolute Peak oxygen consumption	Measured by an open-circuit spirometry system. Absolute value expressed in litres of oxygen per minute (L/min).	Change from baseline. Measured at baseline and after 4, and 8 weeks.
Relative Peak oxygen consumption	Measured by an open-circuit spirometry system. Relative to body weight and expressed in milliliters of oxygen per minute (mL/kg/min).	Change from baseline. Measured at baseline and after 4, and 8 weeks.
Fasting Leptin Levels	Measured by enzyme-Linked Immunosorbent Assay	Change from baseline. Measured at baseline and after 8 weeks.
Fasting Adiponectin Levels	Measured by enzyme-Linked Immunosorbent Assay	Change from baseline. Measured at baseline and after 8 weeks.
Inflammatory Markers Levels	Including but not limited to TNF-α (tumor necrosis factor-alpha) and IL-10 (Interleukin-10); Measured by enzyme-Linked Immunosorbent Assay	Change from baseline. Measured at baseline and after 8 weeks.
LDL-cholesterol levels	Measured using the Friedewald equation.	Change from baseline. Measured at baseline and after 8 weeks.
Non-HDL-cholesterol levels	Calculated as total cholesterol minus HDL-cholesterol.	Change from baseline. Measured at baseline and after 8 weeks.

Collaborators and Investigators

• Sponsor: Federal University of Rio Grande do Sul

Study record dates

Study Major Dates

• Study Start (Estimated): March 1, 2024
• Primary Completion (Estimated): December 1, 2024
• Study Completion (Estimated): December 1, 2024

Study Registration Dates

• First Submitted: February 19, 2024
• First Submitted That Met QC Criteria: March 1, 2024
• First Posted (Actual): March 8, 2024

Study Record Updates

• Last Update Posted (Actual): March 8, 2024
• Last Update Submitted That Met QC Criteria: March 1, 2024
• Last Verified: March 1, 2024

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Overnutrition; Nutrition Disorders; Body Weight; Obesity; Overweight
• Other Study ID Numbers: 16690919.5.0000.5347

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No