Time-Restricted Eating, Exercise and Cardiometabolic Health in Obesity

Impact of Time-Restricted Eating and Supervised Exercise on Hepatic Steatosis and Cardiometabolic Health in Adults With Obesity

In Spain, overweight and obesity prevalence is reaching 70% in men and 50% in women. Excess of triglycerides are usually stored in the subcutaneous adipose tissue (SAT), until a point where SAT is unable to expand further. Therefore, lipids are deposited in visceral and other peripheral organs and tissues that are not otherwise designed for adipose storage such as the liver, pancreas or the skeletal muscle, a process known as ectopic fat deposition. "Time-restricted eating" (TRE) is a recently emerged intermittent fasting approach which has the potential to maximize the beneficial metabolic effects extensively reported for energy intake restriction. Furthermore, exercise reduces hepatic steatosis and improves cardiometabolic health in humans. However, whether the effects of TRE combined with exercise on reducing hepatic steatosis are superior to TRE or exercise intervention alone remains unknown. The TEMPUS study will investigate the effects of a 12-week TRE combined with supervised exercise intervention, as compared with TRE or exercise alone, and usual-care control group, on hepatic fat (primary outcome) and cardiometabolic health (secondary outcomes) in adults with obesity; and to unveil the role of gut microbiota.

Inclusion Criteria:

• Aged 25-65 years.
• Body mass index ≥28.0 and <40.0 kg/m2.
• Weight stability (within 5% of screening weight) for >3 months prior to study entry.
• Habitual eating window ≥11 hours.

Exclusion Criteria:

• History of a major adverse cardiovascular event, clinically significant kidney, endocrine, or neurological disease, bariatric surgery, HIV/AIDS, known inflammatory and/or rheumatologic disease, cancer, or other medical condition in which fasting or exercise is contraindicated.
• Type 1 or Type 2 diabetes.
• Major psychiatric disorders, eating disorders, sleep disorders, or alcohol abuse.
• Regular use of medication or compounds that may affect study outcomes (e.g., antidiabetic, steroids, beta-blockers, antibiotics, prebiotics, probiotics and symbiotics).
• Participating in a weight loss, a weight-management program or a supervised exercise program (more than 30 minutes three times per week, or 45 minutes twice a week, moderate/vigorous intensity).
• Pregnancy and lactation or planned pregnancy (within the study period).
• Caregiver for a dependent requiring frequent nocturnal care/sleep interruptions. Shift workers with variable hours (e.g., nocturnal).
• Frequent travel over time zones during the study period.
• Fear of needles and claustrophobia to magnetic resonance imaging (MRI).
• Being unable to understand and to accept the instructions or the study objectives and protocol.