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Dileucine and Resistance Training Adaptations

Not Applicable
Completed
Conditions
Hypertrophy
Weight-Bearing Strengthening Program
Strength Training Adaptations
Interventions
Dietary Supplement: Dileucine
Dietary Supplement: Leucine
Dietary Supplement: Placebo
Registration Number
NCT06121869
Lead Sponsor
Lindenwood University
Brief Summary

This study seeks to compare the observed changes in resistance training adaptations after supplementation of isomolar amounts of leucine or dileucine in healthy resistance-trained men. This will provide a better understanding of supplementation with leucine versus dileucine over a 10-week period in regards to increasing muscular performance.

Detailed Description

The study will be conducted using a randomized, double-blind approach with individuals being provided daily 2-gram doses of leucine, 2-gram doses of dileucine, or a placebo. Daily blinded supplementation will occur each day for a 10-week period of time while completing a heavy resistance training program. Participants follow the resistance training program for a total of 10 weeks. To compare the efficacy of leucine in form of amino acid or dipeptide supplementation on resistance training adaptations, changes in fat-free, lean, and fat mass will be determined using a 4-compartment body composition model. Skeletal muscle cross-sectional area will be assessed using ultrasound. Maximal strength, muscular endurance, and power will also be assessed. Participants will be required to provide weekly compliance and complete one supervised workout per week. After 2, 6, and 10 weeks of following the supplementation and resistance training regimens, participants will return to the laboratory to complete testing bouts consisting of identical assessments of body composition, muscular strength, muscular endurance, lower-body power, and anaerobic capacity. Adverse events related to each supplementation group will be recorded and assessed.

Recruitment & Eligibility

Status
COMPLETED
Sex
Male
Target Recruitment
34
Inclusion Criteria
  • Male
  • Between the ages of 18-39 years of age
  • Currently participating in resistance training exercise
Exclusion Criteria
  • Female
  • Participants who are determined to not be weight stable defined as week 0 and week 2 body mass levels deviating by 3% or more.
  • Any individual who is currently being treated for or diagnosed with a cardiac, respiratory, circulatory, musculoskeletal, metabolic, immune, autoimmune, psychiatric, hematological, neurological or endocrinological disorder or disease.
  • Body mass index > 25 kg/m2. Individuals with a body mass index greater than 25 kg/m2, but a body fat percentage less than 25% fat will be accepted into the study
  • Individuals who present with any previous injury or illness that would prevent them from appropriately completing all exercise lifts.
  • Participants who are not able to fit onto the DEXA table will not be able to participate in the research due to size restrictions of the equipment. This typically includes individuals exceeding 400 pounds or those greater than 6'4".
  • Those individuals with less than 12 months of structured resistance training experience will be excluded from the study.
  • Individuals whose maximal relative upper body strength is below 1.0 will be excluded.
  • Individuals whose maximal relative lower body strength is below 1.5 will be excluded.
  • All participants who DO NOT abstain from taking any additional forms of nutritional supplementation deemed to be ergogenic or that will impact resistance training adaptations (pre-workouts, creatine, beta-alanine, etc.) for four weeks prior to beginning this study and for the entire duration of the study.
  • Individuals who are currently using or have used within the past 12 months anabolic-androgenic steroids.

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
DileucineDileucineParticipants will supplement daily for 10 weeks with 2 grams dileucine (RAMPS, Ingenious Ingredients, TX, USA) in capsule form. On training days, participants will consume their assigned supplement within 60 minutes of completing their workout. On non-training days, participants will consume their assigned supplement with their first meal of the day. All doses will be consumed with 8-12 ounces of water.
LeucineLeucineParticipants will supplement daily for 10 weeks with 2 grams rice leucine in capsule form. On training days, participants will consume their assigned supplement within 60 minutes of completing their workout. On non-training days, participants will consume their assigned supplement with their first meal of the day. All doses will be consumed with 8-12 ounces of water.
PlaceboPlaceboParticipants will supplement daily for 10 weeks with 2 grams rice flower placebo in capsule form. On training days, participants will consume their assigned supplement within 60 minutes of completing their workout. On non-training days, participants will consume their assigned supplement with their first meal of the day. All doses will be consumed with 8-12 ounces of water.
Primary Outcome Measures
NameTimeMethod
Leg Press 1RM10 weeks

Leg Press 1RM will be measured using the leg press (lower-body) exercise.

Fat-Free Mass10 weeks

Fat-free mass will be determined via Dual-Energy X-Ray Absorptiometry

Maximal Isometric Mid-Thigh Pull Force Production10 weeks

Maximal Isometric Mid-Thigh Pull Force Production will be measured using an isometric mid-thigh pull test

Bench Press 1RM10 weeks

Bench Press 1RM will be measured using the bench press (upper-body) exercise.

Secondary Outcome Measures
NameTimeMethod
Extracellular Body Water10 weeks

Extracellular Body Water will be determined via bioelectrical impedance analysis

Bench Press Repetitions to Fatigue10 weeks

Bench Press repetitions to fatigue will be measured using the bench press (upper-body) exercises on four separate occasions (visits 2, 3, 4, and 5). To complete this assessment, study participants will use a load that corresponds to 80% of their Visit 2 1RM for bench press exercise and will be instructed to complete as many repetitions as they can until failure for one set of each exercise. Failure will be defined as resting for more than two seconds throughout any point on the exercise set or technique failure.

Rate of Fatigue10 weeks

Rate of Fatigue will be measured using a Wingate Anaerobic Test lasting 30-seconds at a load set to 7.5% of week 0 body mass

Fat Mass10 weeks

Fat mass will be determined via Dual-Energy X-Ray Absorptiometry

Total body water10 weeks

Total Body Water will be determined via bioelectrical impedance analysis

Maximal Concentric Rate of Force Development10 weeks

Maximal concentric rate of force development will be measured using a countermovement jump performed on a force plate

% Body Fat10 weeks

% Body Fat will be determined via Dual-Energy X-Ray Absorptiometry

Leg Press Repetitions to Fatigue10 weeks

Leg Press repetitions to fatigue will be measured using the leg press (lower-body) exercises on four separate occasions (visits 2, 3, 4, and 5). To complete this assessment, study participants will use a load that corresponds to 80% of their Visit 2 1RM for leg press exercise and will be instructed to complete as many repetitions as they can until failure for one set of each exercise. Failure will be defined as resting for more than two seconds throughout any point on the exercise set or technique failure.

Peak Anaerobic Power10 weeks

Peak Anaerobic Power will be measured using a Wingate Anaerobic Test lasting 30-seconds at a load set to 7.5% of week 0 body mass

Lean mass10 weeks

Lean mass will be determined via Dual-Energy X-Ray Absorptiometry

Intracellular Body Water10 weeks

Intracellular Body Water will be determined via bioelectrical impedance analysis

Skeletal muscle cross-sectional area10 weeks

Skeletal muscle cross-sectional area will be measured using ultrasound measurements of the participants thigh muscles.

Mean Anaerobic Power10 weeks

Mean Anaerobic Power will be measured using a Wingate Anaerobic Test lasting 30-seconds at a load set to 7.5% of week 0 body mass

Trial Locations

Locations (1)

Exercise and Performance Nutrition Laboratory

🇺🇸

Saint Charles, Missouri, United States

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