Fasting for 84 Hours: How It Affects Fat Burning and Muscle Basics in Young Adults

Is this trial a fit for you?

A plain-English reading of the study's rules. Only the study team can confirm whether you qualify.

What this trial studies

Four groups of young adults (10 per group) will fast for 84 hours and have measurements taken before and after. The study uses DXA for body composition, indirect calorimetry for resting energy expenditure, blood tests, and tissue biopsies from muscle and abdominal fat. Participants follow a measured dietary and activity plan before testing and consent is obtained after information is provided. The goal is to see if fasting alters fat metabolism and tissue properties differently by weight status and sex.

Why it matters

Who can join: the full rules

Inclusion Criteria:

* Healthy normal weight men aged \[18,40\] and BMI \[18,25\]
* Healthy normal weight women \[18,40\] and BMI \[18,25\]
* Healthy obese men \[18,40\] and BMI \[30,40\]
* Healthy obese women \[18,40\] and BMI \[30,40\]

Exclusion Criteria:

* Present or former cardiovascular disease and chronical inflammatory disease
* Consumption of medications and supplements that influence substrate use at rest and/or during exercise
* Pregnancy

Where it's running

• Department of Biomedical Sciences
  Copenhagen, Denmark Recruiting

Study contacts

• Study coordinator: Jørn W Helge, PhD
• Email: jhelge@sund.ku.dk
• Phone: +4528757506

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How to take part

1. Review the eligibility criteria above with your treating physician.
2. Check the official listing on ClinicalTrials.gov for the latest contact details and recruitment status.
3. Contact the study coordinator or principal investigator to ask for pre-screening. Pre-screening is free and never obligates you to enroll.