Dose Response of Leucine on Muscle Maintenance During Weight Loss

NCT07583875 | Completed DMC

• 1 other identifier: IRB 2019-07-039
• Study Type: interventional
• Target: 92
• Locations: 1 country
• Sites: 1

Brief Summary

The objective of this research is to determine if there is dose response of leucine on muscle maintenance during 4-week of alternate-day fasting (ADF) on blood parameters, body composition, mood and parameters related to appetite in young men with a body mass index of 23kg/m2 and above, whose body mass falls outside of the healthy range for their height (Asian reference point for increased risk of cardiovascular diseases). Participants have no diagnoses of, and are not prescribed medications for, cardiovascular, metabolic, diabetic, lung (except controlled asthma), kidney, or joint health conditions. To achieve this objective, 100 hundred young men, aged between 21 and 35 years old will be recruited to complete a 4-week ADF programme. The fasting programme starts at 12 midnight and alternates between fasting and feeding days. Each fasting or feeding day is 24-hour in duration. During the fasting days, participants will abstain from all food and beverages except for ad libitum intake of plain water and other zero caloric beverages, and a small meal that is \~25% of daily caloric need. This small meal must be consumed during 12 pm to 2 pm in this study for standardisation to ensure consistency in total duration of fasting and feeding. During the feeding days, participants will eat up to \~125% of daily caloric need (calculated every week) with no restriction on the timing of meals as long as they are within the 24-hour period. The programme will end after 4 weeks (28 days) of continuous ADF. All food for the 4-week ADF will be provided. Protein intake will be up to \~1.2 g/kg body mass/day on fasting day and up to \~2.4 g/kg body mass/day (\~32-40% of calories) on feeding days. Participants will be randomly assigned (double blind) to the amount of leucine in their diet: 0.02, 0.04, 0.06 or 0.08 g/kg body mass per meal for 1 meal/day on fasting days and 3 meals/day on feeding days. Blood parameters, body mass, height, waist-to-hip ratio, body composition, mood, stress level, and parameters related to eating and appetite will be measured before and after 4-week of ADF. The investigators hypothesised a dose response in leucine to maintain muscle mass during weight loss.

Conditions

BMI >= 23; Overweight and Obese Adults

Keywords

Overweight; Obesity; Intermittent fasting; Alternate Day Fasting; ADF; Protein; Leucine; Skeletal muscle; quality weight loss; dose response; muscle maintenance; blood health markers; mood; appetite; food craving

Outcome Measures

Primary Outcomes (23)

• Body mass

  Body mass measured using BIA weighing scale

  Start and end of 4-week intervention and weekly during intervention

• Lean mass

  Lean mass measured using DXA

  Start and end of 4-week intervention

• Appendicular Lean Mass

  Sum of lean mass in upper and lower limbs measured using DXA

  Start and end of 4-week intervention

• Body mass index

  body mass in kilograms divided by sqaure of height in metres

  Start and end of 4-week intervention and weekly during intervention

• Lean mass index

  lean mass in kilograms divided by square of height in metres

  Start and end of 4-week intervention

• Appendicular lean mass index

  Appendicular lean mass in kilograms divided by square of height in metres

  Start and end of 4-week intervention

• Fat mass

  Fat mass

  Start and end of 4-week intervention and weekly during intervention

• Percentage body fat

  Percentage body fat

  Start and end of 4-week intervention and weekly during intervention

• Fat mass index

  Fat mass in kilograms divided by square of height in metres

  Start and end of 4-week intervention and weekly during intervention

• Trunk fat

  Fat mass around the trunk

  Start and end of 4-week intervention

• Appendicular fat mass

  Sum of fat mass in the upper and lower limbs

  Start and end of 4-week intervention

• Appendicular fat-free mass index

  Appendicular fat-free mass in kilograms divided by square of height in metres

  Start and end of 4-week intervention and weekly during intervention

• Resting systolic blood pressure

  Start and end of 4-week intervention and weekly during intervention

• Resting diastolic blood pressure

  Start and end of 4-week intervention and weekly during intervention

• Fasting blood glucose

  Start and end of 4-week intervention and weekly during intervention

• HbA1c

  Start and end of 4-week intervention

• Insulin

  Start and end of 4-week intervention

• The HOMA-IR index

  Homeostatic Model Assessment of Insulin Resistance index

  Start and end of 4-week intervention

• Total cholesterol

  Start and end of 4-week intervention

• HDL cholesterol

  Start and end of 4-week intervention

• LDL cholesterol

  Start and end of 4-week intervention

• Total cholesterol to HDL cholesterol ratio

  Start and end of 4-week intervention

• Triglycerides

  Start and end of 4-week intervention

Secondary Outcomes (26)

• Android fat mass

  Start and end of 4-week intervention

• Gynoid fat mass

  Start and end of 4-week intervention

• Bone mineral content

  Start and end of 4-week intervention

• Bone mineral density

  Start and end of 4-week intervention

• Waist Circumference

  Start and end of 4-week intervention and weekly during intervention

Other Outcomes (13)

• Height

  Start and end of 4-week intervention and weekly

• Hydration status

  Start and end of 4-week intervention and weekly during intervention

• SGP/ALT

  Start and end of 4-week intervention

Study Arms (4)

0.02g/kg body mass per meal/day

EXPERIMENTAL

In this study, participants would be randomly (by chance) assigned to the amount of leucine in their diet: 0.02, 0.04, 0.06 or 0.08 g/kg body mass per meal for 1 meal/day on fasting days and 3 meals/day on feeding days.

Dietary Supplement: leucine

0.04g/kg body mass per meal/day

EXPERIMENTAL

In this study, participants would be randomly (by chance) assigned to the amount of leucine in their diet: 0.02, 0.04, 0.06 or 0.08 g/kg body mass per meal for 1 meal/day on fasting days and 3 meals/day on feeding days.

Dietary Supplement: leucine

0.06g/kg body mass per meal/day

EXPERIMENTAL

In this study, participants would be randomly (by chance) assigned to the amount of leucine in their diet: 0.02, 0.04, 0.06 or 0.08 g/kg body mass per meal for 1 meal/day on fasting days and 3 meals/day on feeding days.

Dietary Supplement: leucine

0.08g/kg body mass per meal/day

EXPERIMENTAL

In this study, participants would be randomly (by chance) assigned to the amount of leucine in their diet: 0.02, 0.04, 0.06 or 0.08 g/kg body mass per meal for 1 meal/day on fasting days and 3 meals/day on feeding days.

Dietary Supplement: leucine

Interventions

leucine DIETARY_SUPPLEMENT

0.02g/kg body mass/meal/day

0.02g/kg body mass per meal/day

Eligibility Criteria

• Age: 21 Years - 35 Years
• Healthy Volunteers: No
• Age Groups: Adult (18-64)

You may qualify if:

• Male
• to 35 years old
• Do not smoke or use tobacco products (including shisha)
• Have a body mass index (BMI = body mass in kilograms divided by the square of height in metres) of 23 or greater

You may not qualify if:

• Unable to adhere to the requirements regarding physical activity and diet as stated in the research methodologies.
• Allergic or intolerant to milk and soy.
• Any other food allergies or dietary restrictions/preferences that the research team is unable to cater to due to constraints in food preparation and choices in order to control for composition of macronutrients, leucine content and calories in the food provided.
• Failed an exercise stress test.
• Have any health condition(s) that would be made worse by fasting.
• Taking long-term prescribed medication(s) for heart, blood (including blood sugar and blood pressure), lung (except controlled asthma), liver, kidney or joint condition(s).
• Taking other prescribed medication (including traditional Chinese medicine and other alternative medicine), drugs, steroids, or hormones that can affect any of the measurements in this study.
• Have electrical implant (such as pacemaker, implantable cardioverter defibrillator or neurostimulator), metal or plastic implant/rod/plate, or joint replacement in the body as these objects can affect the accuracy of the body composition measurement.

Sponsors & Collaborators

• Nanyang Technological University: lead
• Ministry of Education, Singapore: collaborator

Study Sites (1)

Nanyang Technological University

Singapore, 637616, Singapore

Location

MeSH Terms

Conditions

Overweight; Obesity; Intermittent Fasting

Interventions

Leucine

Condition Hierarchy (Ancestors)

Overnutrition; Nutrition Disorders; Nutritional and Metabolic Diseases; Body Weight; Signs and Symptoms; Pathological Conditions, Signs and Symptoms; Fasting; Feeding Behavior; Behavior

Intervention Hierarchy (Ancestors)

Amino Acids, Branched-Chain; Amino Acids; Amino Acids, Peptides, and Proteins; Amino Acids, Essential

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: TRIPLE
• Who Masked: PARTICIPANT, INVESTIGATOR, OUTCOMES ASSESSOR
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Model Details: This was a four-arm randomized controlled trial with a double-blind design

Study Record Dates

• First Submitted: April 26, 2026
• First Posted: May 13, 2026
• Study Start: August 18, 2020
• Primary Completion: February 11, 2021
• Study Completion: February 11, 2021
• Last Updated: May 13, 2026

Record last verified: 2026-04

Data Sharing

• IPD Sharing: Will share
• Shared Documents: STUDY PROTOCOL, SAP, ICF
• Access Criteria: Individual participant data (IPD) will be made available to qualified researchers upon request. To access the data, researchers must submit a formal request, which will be reviewed and approved by the data sharing committee. Data access will be granted for research purposes only and will require adherence to data use agreements and ethics guidelines.

Locations

SG (1)