Prolonged Overnight Fast, Energy Metabolism and Skeletal Muscle Anabolic Sensitivity

November 18, 2025 updated by: Kostas Tsintzas, University of Nottingham

The Effect of Prolonged Overnight Fast on Postprandial Energy Metabolism and Skeletal Muscle Anabolic Sensitivity in Healthy Humans

Recent research shows that timing of nutritional intake and daily periods of fasting may have important health effects. In humans, limiting daily food intake to a narrow window (typically ~8 hours) can bring about some beneficial changes in blood concentrations of fats, sugar and the hormone insulin. It is thought that many of these changes are due to the prolonged daily fasting periods and humans will have regularly experienced prolonged fasting periods throughout evolution. In the modern era, food access is widely available and it is not uncommon for the time between breakfast and a late night snack to exceed 14 hours. We have recently shown that extending habitual daily periods of fasting to 16 hours per day also improves the ability of skeletal muscle to take up amino acids, the building blocks of protein. We are interested in studying whether a single episode of prolonged overnight fast (~16 hours), when compared to a normal overnight fast of 10 hours, is sufficient to stimulate skeletal muscle protein synthesis in response to dietary protein ingestion in healthy humans.

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Completed

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Detailed Description

There is a growing interest in the cardiometabolic benefits of various intermittent fasting paradigms (such as alternate day fasting and the 5:2 fast diet), where periods of normal energy intake are punctuated by periods of energy restriction or fasting. A recent alternative to these protocols is time-restricted feeding (TRF), which limits daily food/energy intake to a narrow window (typically 8 to 10h). The major strength of TRF is that it extends the duration of overnight fast without limiting normal calorie intake. Recent evidence from both animal and human studies have shown that habitual daily periods of fasting of as little as 16h can reduce fasting insulin and triglycerides levels, protect against excessive body weight gain in response to high fat and sucrose diets, better maintain fat-free mass, and improve beta-cell responsiveness. We recently completed a 2-week TRF intervention study using the 8h fed (between 8am and 4pm)/16h fast protocol in healthy individuals and found improvements in insulin sensitivity and skeletal muscle uptake of branched chain amino acids. As we did not make measurements of muscle protein synthesis, it is not known whether a single episode of prolonged overnight fast (~16h) is sufficient to elicit improvements in insulin sensitivity and stimulate skeletal muscle protein synthesis in response to dietary protein ingestion. The aim of the proposed study is to investigate the effect of prolonged overnight fast (16h vs. 10h) on postprandial energy metabolism and skeletal muscle protein synthesis in healthy humans.

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Interventional

Enrollment (Actual)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
9

Phase

Phase

The stage of a clinical trial studying a drug or biological product, based on definitions developed by the U.S. Food and Drug Administration (FDA). The phase is based on the study's objective, the number of participants, and other characteristics. There are five phases: Early Phase 1 (formerly listed as Phase 0), Phase 1, Phase 2, Phase 3, and Phase 4. Not Applicable is used to describe trials without FDA-defined phases, including trials of devices or behavioral interventions.
  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact

The name and contact information for the person who can answer enrollment questions for a clinical study. Each location where the study is being conducted may also have a specific contact, who may be better able to answer those questions.

Study Contact Backup

Study Locations

  • United Kingdom
    • Nottinghamshire
      • Nottingham, Nottinghamshire, United Kingdom, NG7 2UH
        • University of Nottingham

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

18 years to 35 years (Adult)

Accepts Healthy Volunteers

Yes

Description

Inclusion Criteria:

  • Male
  • 18-35yrs
  • healthy
  • non-smoking
  • physically active
  • no excessive weight loss in past 6 months
  • body mass index between 18 and 27 kg.m-2

Exclusion Criteria:

  • body mass index under 18 and over 27 kg.m-2
  • sedentary
  • screening bloods out of range
  • excessive weight loss in the past 6 months
  • irregular eating patterns

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Basic Science
  • Allocation: Randomized
  • Interventional Model: Crossover Assignment
  • Masking: Single

Arms and Interventions

Participant Group / Arm

Participant Group / Arm

A group or subgroup of participants in a clinical trial that receives a specific intervention/treatment, or no intervention, according to the trial's protocol.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
Other: Short Fast
Participants will fast overnight for a period of 10 hours
Other: Short 10hr fast
Participants will fast from 11pm the night before the study day
Other: Long fast
Participants will fast overnight for a period of 16 hours
Other: Long 16h fast
Participants will fast from 5pm the night before the study day

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Measure Description
Time Frame
Whole body Insulin sensitivity
Time Frame: 3 hours
Postprandial blood glucose and serum insulin concentrations will be used to compute the Matsuda index of whole body insulin sensitivity. Postprandial blood glucose and serum insulin concentrations will be measured every 15mins for 3 hours in response to ingestion of a protein and dextrose drink. Serum insulin concentration (mIU/l) will be measured either with an enzyme linked immunosorbent assay or a radioimmuno assay. Blood glucose will be measured using the glucose oxidase method.
3 hours
Glycemic responses
Time Frame: 3 hours
Postprandial blood glucose incremental area under the curve( iAUC)
3 hours
Insulinaemic responses
Time Frame: 3 hours
Postprandial blood insulin iAUC
3 hours
Index of skeletal muscle protein synthesis (A)
Time Frame: 3 hours
Skeletal muscle branched chain amino acid uptake using postprandial arteriovenous differences.
3 hours
Index of skeletal muscle protein synthesis (B)
Time Frame: 3 hours
Muscle protein synthesis will be measured 3 hours after ingestion of a protein and dextrose drink in which the milk protein has been intrinsically labelled with [1-13C]phenylalanine. The investigators will measure [13C]phenylalanine incorporation into the muscle myofibrillar protein pool during the 3 hour period from a muscle biopsy sample taken pre ingestion of the drink and a muscle biopsy taken 3 hours post ingestion. This will give a rate (%/hour) of muscle protein synthesis.
3 hours

Secondary Outcome Measures

Secondary Outcome Measures

In a clinical study's protocol, a planned outcome measure that is not as important as the primary outcome measure for evaluating the effect of an intervention but is still of interest. Most clinical studies have more than one secondary outcome measure.
Outcome Measure
Measure Description
Time Frame
Skeletal muscle insulin sensitivity
Time Frame: 3 hours
Postprandial arteriovenous differences in glucose concentration. Blood glucose in arterialised and deep venous blood across the forearm will be measured using the glucose oxidase method.
3 hours

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
University of Nottingham

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
May 30, 2019

Primary Completion (Actual)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
March 19, 2024

Study Completion (Actual)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
March 19, 2024

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
April 8, 2022

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
June 14, 2022

First Posted (Actual)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
June 15, 2022

Study Record Updates

Last Update Posted (Actual)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
November 24, 2025

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
November 18, 2025

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
November 1, 2025

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • 289-1904

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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