The Fuel and Rhythm (FAR) Phase 2 Study

NCT ID: NCT05482711

Last Updated: 2026-01-14

Study Results

Results pending

The study team has not published outcome measurements, participant flow, or safety data for this trial yet. Check back later for updates.

Basic Information

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Recruitment Status

ACTIVE_NOT_RECRUITING

Clinical Phase

NA

Total Enrollment

15 participants

Study Classification

INTERVENTIONAL

Study Start Date

2023-01-10

Study Completion Date

2026-03-31

Brief Summary

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Both fuel metabolism and circadian rhythms have emerged as important targets to improve cellular and mitochondrial health and ultimately affect function in older adults. Thus, the purpose of this study is to develop minimally invasive measures that will allow us to accurately assess and detect changes in fuel metabolism and circadian rhythms in older adults following time-restricted eating.

Detailed Description

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A growing body of evidence indicates the mitochondria have an important role in the etiologies of many chronic diseases as well as the onset of physical disability in older adults. Although it is recognized that the mitochondria have an important role in many functions relevant to healthy aging, the direct assessment of mitochondrial function in humans is complicated and typically involves a muscle biopsy. Muscle tissue obtained from a biopsy can be used to provide an index of mitochondrial function, but only at a single time point. Some individuals may be discouraged from participating in research studies involving biopsies due to the perceived pain and risk involved.

Why there is a decrease in mitochondrial function with aging remains under debate, but emerging science indicates that there is a clear connection between mitochondrial biogenesis and function with fuel metabolism and circadian rhythms. Thus, the purpose of this development project is to develop relatively non-invasive measures that are sensitive to fuel metabolism and circadian health which can serve studies conducted within the University of Florida's Pepper Center in the coming years. In the proposed project, we will investigate the extent to which our measures of fuel utilization and circadian health markers are time stable and also sensitive to change following an intervention of time restricted eating, which is expected to impact these variables.

To our knowledge, no study has assessed fuel utilization patterns or circadian health markers in overweight older adults. Measurements of altered mitochondrial oxidation with a preference toward fat metabolism obtained from a blood sample would provide a sensitive biomarker that is relatively easy to obtain from participants for future interventions studies. The use of continuous glucose monitoring may also be used as surrogate measure of adherence to lifestyle interventions involving calorie restriction and/or intervention fasting, in future studies.

In addition to fuel utilization, there is growing recognition that age-related disease conditions and functional decline are associated with disruption of circadian rhythms. These observations raise the possibility that targeting circadian rhythms through timing lifestyle cues, such as meal timing, could be health promoting and may also reduce age associated declines in mobility. The ability to assess markers of circadian and metabolic health in minimally invasive ways through temperature and glucose monitoring, will provide potential valuable measures for explanatory or outcome measures in future studies.

Conditions

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Aging

Study Design

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Allocation Method

NA

Intervention Model

SINGLE_GROUP

Primary Study Purpose

PREVENTION

Blinding Strategy

NONE

Study Groups

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Time Restricted Eating intervention

Participants will be asked to stop eating by 7 PM every day and to fast for a target of 16 hours per day for 8 weeks. During the first two weeks of the intervention, participants will gradually ramp up to a full 16-hour fasting period (Week 1 - fast for 12-14 hours per day, Week 2 - fast for 14-16 hours per day, Week 3 - 8 - fast for 16 hours per day). Participants will be allowed to consume calorie-free beverages, tea, black coffee, sugar-free gum, and they will be encouraged to drink plenty of water throughout the entire intervention period. Additionally, they will be asked to keep a Fasting and Sleeping diary logging their eating habits and sleep quality.

Group Type OTHER

Time Restricted Eating Intervention

Intervention Type OTHER

All participants will be asked to adhere to suggested fasting and feeding periods throughout the 8 week study period. These participants will self-monitor eating and sleeping habits as well to present to study staff at checkpoints. Self-reported information will be used during group-mediated intervention sessions throughout the duration of the study, as well.

Interventions

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Time Restricted Eating Intervention

All participants will be asked to adhere to suggested fasting and feeding periods throughout the 8 week study period. These participants will self-monitor eating and sleeping habits as well to present to study staff at checkpoints. Self-reported information will be used during group-mediated intervention sessions throughout the duration of the study, as well.

Intervention Type OTHER

Eligibility Criteria

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Inclusion Criteria

* Consent to participate in the study
* Men and women ≥ 65 years old
* Self-reported difficulty walking ¼ mile or climbing a flight of stairs
* Self-reported sedentariness (\<150 minutes structured exercise per week)
* Walking speed \<1 m/sec on the 4 m walk test
* Able to walk unassisted (cane allowed)
* Have a body mass index between 25 - 40 kg/m2 (inclusive)
* HbA1c \< 5.7 %

Exclusion Criteria

* Fasting \>12 hours per day
* Actively trying to lose weight by participating in formal weight loss program or significantly restricting calorie intake
* Resting heart rate of \>120 beats per minute, systolic blood pressure \> 180 mmHg and/or diastolic blood pressure of \> 100 mmHg
* Unstable angina, heart attack or stroke in the past 3 months
* Continuous use of supplemental oxygen to manage a chronic pulmonary condition or heart failure
* Rheumatoid arthritis, Parkinson's disease or currently on dialysis
* Active treatment for cancer in the past year
* Diabetes Mellitus
* Known history of skin sensitivity or allergic reaction to adhesives
* Taking medications that preclude fasting for 16 hours (e.g. must be taken with food at least 12 hours apart)
* Any condition that in the opinion of the investigator would impair ability to participate in the trial
Minimum Eligible Age

65 Years

Eligible Sex

ALL

Accepts Healthy Volunteers

Yes

Sponsors

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National Institute on Aging (NIA)

NIH

Sponsor Role collaborator

University of Florida

OTHER

Sponsor Role lead

Responsible Party

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Responsibility Role SPONSOR

Principal Investigators

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Stephen Anton, Ph.D.

Role: PRINCIPAL_INVESTIGATOR

University of Florida

Locations

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University of Florida

Gainesville, Florida, United States

Site Status

Countries

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United States

References

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Provided Documents

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Document Type: Informed Consent Form

View Document

Other Identifiers

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P30AG028740

Identifier Type: NIH

Identifier Source: secondary_id

View Link

IRB202102618 -N

Identifier Type: -

Identifier Source: org_study_id

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