The Impact of a 48-hour Fast with or Without Exercise on Immune Cell Metabolism and Glycemic Control in Healthy Active Adults

NCT06737224 | Recruiting

• 1 other identifier: H24-01732
• Study Type: interventional
• Target: 15
• Locations: 1 country
• Sites: 1

Brief Summary

Many individuals engage in fasting for its purported health benefits but the effects of fasting on immune cell and whole body metabolism are not well understood in humans. Moreover, how exercising during a prolonged fast impacts immunometabolic outcomes is unclear. This study will determine how a 2 day fast - performed with or without daily exercise - impacts immune cell bioenergetics, immune cell function, and whole-body glycemic control in healthy active individuals.

Conditions

Fasting; Immune Function; Glucose Tolerance

Keywords

Exercise; Immunometabolism; Glycemic control

Outcome Measures

Primary Outcomes (1)

• Monocyte mitochondrial respiration

  Mitochondrial respiration will be measured in primary human monocytes using high resolution respirometry before and after a 48-hour fast performed with or without exercise.

  Baseline and 48 hours

Secondary Outcomes (11)

• Alteration in immune cell functions

  Baseline and 48 hours

• Change in glucose tolerance

  Baseline, after 48 hours of fasting, and 24 hours after breaking the fast in free-living condition)

• Blood pressure

  Baseline, 24 hours into the fast, and at the end of the fast (48 hours)

• Rate and level of ketosis

  Baseline, 24 hours and 48 hours during fasting

• Compensatory movement behaviour

  During and 48 hours after the fast

Study Arms (2)

Fasting + Exercise (FAST+EX): fasting + exercise condition

EXPERIMENTAL

48-hour fast with 60 minutes of cycling on the first and second day of the fast.

Other: Fasting + Exercise (FAST+EX): fasting + exercise condition

Fasting only (FAST): Non-exercise fasting condition

EXPERIMENTAL

48-hour fast with no structured exercise on fasting days.

Other: Fasting only (FAST): Non-exercise fasting condition

Interventions

Fasting + Exercise (FAST+EX): fasting + exercise condition OTHER

Participants will complete a 48-hour fast. One hour of exercise will be performed on each morning of the fast.

Fasting + Exercise (FAST+EX): fasting + exercise condition

Fasting only (FAST): Non-exercise fasting condition OTHER

Participant will complete a 48-hour fast. No structured exercise will be performed during each of the fasting days.

Fasting only (FAST): Non-exercise fasting condition

Eligibility Criteria

• Age: 19 Years - 35 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Aged between 19 and 35 years.
• Physically active (engaging in ≥150 minutes of weekly moderate to vigorous physical activity).

You may not qualify if:

• History of cardiometabolic diseases or inflammatory diseases (e.g., chronic obstructive pulmonary disease (COPD), rheumatoid arthritis, cardiovascular disease).
• Individuals currently following a ketogenic diet, low-calorie diet, periodic fasting regimen, or consuming ketogenic supplements (e.g., exogenous ketone drinks).
• Cigarette/vaping smoking.
• Physical limitation that will impair the ability of the participant to perform exercise.
• Individuals having a body mass index (BMI) over 30 kg/m2.
• Cancer diagnosis in the past 5 years.
• Taking anti-inflammatory drugs (e.g., ibuprofen, aspirin, naproxen).
• Being unable to read or communicate in English.

Sponsors & Collaborators

• University of British Columbia: lead

Study Sites (1)

University of British Columbia Okanagan Campus

Kelowna, British Columbia, V1V1V7, Canada

RECRUITING

MeSH Terms

Conditions

Fasting; Motor Activity

Interventions

Exercise

Condition Hierarchy (Ancestors)

Feeding Behavior; Behavior

Intervention Hierarchy (Ancestors)

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

Central Study Contacts

Jonathan Little Principal Investigator, Professor Little, Ph.D

CONTACT

250-807-9876; jonathan.little@ubc.ca

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: OUTCOMES ASSESSOR
• Purpose: OTHER
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Professor

Model Details: Randomized crossover, within-subject, repeated measures

Study Record Dates

• First Submitted: October 8, 2024
• First Posted: December 17, 2024
• Study Start: January 10, 2025
• Primary Completion: August 1, 2025
• Study Completion: August 1, 2025
• Last Updated: March 7, 2025

Record last verified: 2025-03

Data Sharing

• IPD Sharing: Will not share

Locations

CA (1)