Recruiting

48-Hour Fast

Sponsor:

University of British Columbia

Code:

NCT06737224

Conditions

Fasting

Immune Function

Glucose Tolerance

Eligibility Criteria

Sex: All

Age: 19 - 35

Healthy Volunteers: Accepted

Interventions

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

Fasting only (FAST): Non-exercise fasting condition

Study Details

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

Study ID

NCT06737224

Start date

Jan 10, 2025

Status verified date

Mar, 2025

Completion date

Aug 1, 2025

Anticipated

Primary completion date

Aug 1, 2025

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: All

Age: 19 - 35

Healthy Volunteers: Accepted

Inclusion Criteria:

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

Exclusion Criteria:

  • 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.

Study Design

Enrollment

15 participants

Anticipated

Allocation

Randomized

Intervention Model

Crossover

Primary purpose

Other

Interventions and Outcome Measures

Arms

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

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

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

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

Interventions

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

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

Fasting only (FAST): Non-exercise fasting condition

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

Primary outcome measure

  • Monocyte mitochondrial respiration [ Time Frame: Baseline and 48 hours ]

Central Contacts and Locations

Central contacts

Jonathan Little Principal Investigator, Professor Little, Ph.D

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

Locations

University of British Columbia Okanagan Campus

Recruiting

Kelowna, British Columbia, Canada, V1V1V7

Contacts

Alexis Marcotte-Chénard Postdoctoral fellow, Ph.D

250-807-9876alexis.marcottechenard@ubc.ca

More Information

Sponsor

University of British Columbia

Last update posted

Mar 7, 2025

Last verified

Mar, 2025

Keywords

  • Exercise
  • Immunometabolism
  • Glycemic control

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-10. This information was provided to ClinicalTrials.gov by University of British Columbia on 2025-03-07.