Exercise and Prolonged Fasting to Improve Brown Adipose Tissue Function in Postmenopausal Women

NCT07837752 | Not Yet Recruiting

• 1 other identifier: PID2025-173649OB-I00
• Study Type: interventional
• Target: 60
• Locations: 1 country
• Sites: 1

Brief Summary

Type of Study: Clinical Trial Goal: The goal of this clinical trial is to investigate mitochondrial function in interscapular brown adipose tissue (iBAT) in postmenopausal women and determine whether aerobic exercise, prolonged fasting, or their combination can improve iBAT mitochondrial function and whole-body metabolic flexibility. Participant Population/Health Conditions: The study will involve 60 postmenopausal women aged 45-65 years living with overweight or obesity. Main Questions: The main questions this study aims to answer are:

• What are the mitochondrial function and cellular characteristics of iBAT in postmenopausal women?
• Can aerobic exercise or five-day prolonged fasting improve mitochondrial function in iBAT and whole-body metabolic flexibility?
• Does combining aerobic exercise with prolonged fasting produce greater metabolic adaptations than either intervention alone?
• Are improvements in metabolic flexibility maintained four weeks after the intervention? Participants Will: Be randomized into one of four groups: control, aerobic exercise, prolonged fasting, or combined aerobic exercise plus prolonged fasting. Follow their assigned intervention for five consecutive days. Undergo metabolic and physiological assessments before and after the intervention and again four weeks later. Provide dorsocervical adipose tissue biopsies and biological samples to investigate mitochondrial function, adipocyte characteristics, and metabolic adaptations. Comparison Group: Researchers will compare the effects of aerobic exercise, prolonged fasting, and their combination with a control condition to determine their effects on iBAT mitochondrial function and whole-body metabolic flexibility.

Conditions

Cardiometabolic Diseases; Postmenopause

Keywords

Brown adipose tissue; thermogenesis; women; postmenopause; exercise; fasting; metabolic flexibility

Outcome Measures

Primary Outcomes (1)

• iBAT adipocyte composition and gene expression (snRNA-seq)

  Change in adipocyte subpopulations and gene expression in dorsocervical iBAT assessed by single-nucleus RNA sequencing (snRNA-seq)

  1 week

Secondary Outcomes (21)

• iBAT mitochondrial respiration (Oroboros O2k).

  1 week

• iBAT protein expression (Western blot)

  1 week

• Total Body Fat Mass

  5 weeks

• Body Fat Percentage

  5 weeks

• Resting Metabolic Rate

  5 weeks

Study Arms (4)

Control

NO INTERVENTION

n=15; maintaining their usual lifestyle without changes to diet or physical activity; Total 5 days

Aerobic exercise

EXPERIMENTAL

n=15; receiving supervised aerobic exercise for 60-90 minutes/day at 65% of heart rate reserve; Total 5 days

Behavioral: Aerobic exercise

Prolonged fasting

EXPERIMENTAL

n=15; following a prolonged fasting protocol providing approximately 600 kcal/day; Total 5 days

Behavioral: Prolonged fasting

Aerobic exercise + prolonged fasting

EXPERIMENTAL

n=15; receiving supervised aerobic exercise for 60-90 minutes/day at 65% of heart rate reserve and prolonged fasting providing approximately 600 kcal/day; Total 5 days

Behavioral: Aerobic exercise; Behavioral: Prolonged fasting

Interventions

Aerobic exercise BEHAVIORAL

Participants will perform supervised aerobic exercise for 60-90 minutes per day at 65% of heart rate reserve on 5 consecutive days.

Aerobic exercise; Aerobic exercise + prolonged fasting

Prolonged fasting BEHAVIORAL

Participants will follow a medically supervised prolonged fasting protocol providing approximately 600 kcal/day for five consecutive days.

Aerobic exercise + prolonged fasting; Prolonged fasting

Eligibility Criteria

• Age: 45 Years - 65 Years
• Sex: female
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Women aged 45 to 65 years.
• Postmenopausal status, defined as ≥ 12 consecutive months without menstruation.
• Women with amenorrhea shorter than 12 months will be included if their follicle-stimulating hormone levels are \>30IU/liter.
• BMI between ≥25 kg/m2.
• Sedentary or low-active (not meeting physical activity guidelines).
• Willing to be randomized to any of the four groups.
• Able and willing to adhere to all study procedures and show availabity in their schedule.
• Must be willing to have biological samples stored for future research.

You may not qualify if:

• Diabetes mellitus (determined based on fasting glucose levels defined by ADA criteria).
• Any other active endocrine disease (thyroid disease, any signs of Cushing's syndrome, adrenal disease and lipid-associated disorders such as familial hypercholesterolemia).
• Any cardiac disease (i.e., ischemic cardiac disease, arrhythmias, severe heart failure).
• Use of medication known to influence glucose and/or lipid metabolism or brown fat activity (e.g., beta-blockers, antidepressants, corticosteroids).
• Current or recent (past 6 months) use of hormone replacement therapy, including systemic estrogen therapy (oral or transdermal), combined estrogen-progestin therapy, tibolone, or selective estrogen receptor modulators.
• Clinically relevant abnormalities in clinical chemistry or electrocardiogram at screening (to be judged by the study physician).
• A first-degree family member with sudden cardiac death.
• Any chronic renal or hepatic disease.
• Abuse of alcohol or other substances.

Sponsors & Collaborators

• Universidad de Almeria: lead
• Leiden University Medical Center: collaborator
• ETH Zurich (Switzerland): collaborator
• Buchinger Wilhelmi Development & Holding GmbH: collaborator

Study Sites (1)

Universidad de Almería

Almería, Almería, 04131, Spain

Location

MeSH Terms

Conditions

Motor Activity; Fasting

Interventions

Exercise

Condition Hierarchy (Ancestors)

Behavior; Feeding Behavior

Intervention Hierarchy (Ancestors)

Motor Activity; Movement; Musculoskeletal Physiological Phenomena; Musculoskeletal and Neural Physiological Phenomena

Central Study Contacts

Borja Martínez Téllez, PhD

CONTACT

+34 950215334; borjammt@ual.es

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: INVESTIGATOR
• Purpose: BASIC SCIENCE
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Principal Investigator

Model Details: This study will consist of a randomized controlled trial in which 60 postmenopausal women with a BMI ≥27 kg/m² will be randomly assigned (1:1:1:1) to a control group (n=15; maintaining their usual lifestyle), an aerobic exercise group (n=15; supervised exercise for 60-90 minutes/day at 65% heart rate reserve), a prolonged fasting group (n=15; approximately 600 kcal/day), or a combined exercise plus fasting group (n=15; completing both interventions). All interventions will last five consecutive days.

Study Record Dates

• First Submitted: September 9, 2026
• First Posted: September 23, 2026
• Study Start (Estimated): September 1, 2027
• Primary Completion (Estimated): September 1, 2029
• Study Completion (Estimated): September 1, 2029
• Last Updated: September 23, 2026

Record last verified: 2026-09

Data Sharing

• IPD Sharing: Will share
• Shared Documents: STUDY PROTOCOL, ICF, CSR
• Time Frame: 5 years after publishing the data
• Access Criteria: Everybody

Locations

ES (1)