UMIN-ICDS Clinical Trial
| Unique ID issued by UMIN | UMIN000063205 |
|---|---|
| Receipt number | R000072340 |
| Scientific Title | Effects of acute combined ingestion of L-arginine and L-citrulline on resistance exercise performance and muscle soreness: A randomized, double-blind, placebo-controlled, crossover trial |
| Date of disclosure of the study information | 2026/10/07 |
| Last modified on | 2026/10/07 14:57:24 |
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Basic information
Public title
Effects of Combined Ingestion of Arginine and Citrulline on Resistance Exercise Performance and Muscle Soreness
Acronym
Arg-Cit Resistance Exercise Trial
Scientific Title
Effects of acute combined ingestion of L-arginine and L-citrulline on resistance exercise performance and muscle soreness: A randomized, double-blind, placebo-controlled, crossover trial
Scientific Title:Acronym
Effects of acute combined ingestion of L-arginine and L-citrulline on resistance exercise performance and muscle soreness: A randomized, double-blind, placebo-controlled, crossover trial
Region
| Japan |
Condition
Condition
Healthy adults (Volleyball players / Resistance-trained males)
Classification by specialty
| Not applicable | Adult |
Classification by malignancy
Others
Genomic information
NO
Objectives
Narrative objectives1
To evaluate the acute effects of combined L-arginine (Arg) and L-citrulline (Cit) ingestion (low dose: 1.5g each; high dose: 5.0g each) on high-intensity resistance exercise performance (total repetitions in back squat and bench press at 70% 1RM) and post-exercise muscle soreness (VAS at 24, 48, and 72 hours) in healthy resistance-trained adult males using a randomized, double-blind, placebo-controlled crossover trial.
Basic objectives2
Efficacy
Basic objectives -Others
Trial characteristics_1
Exploratory
Trial characteristics_2
Developmental phase
Not applicable
Assessment
Primary outcomes
Total repetitions in high-intensity resistance exercise
1) Repetitions to exhaustion per set and total in back squat (70% 1RM, 6 sets, 1-min interval)
2) Repetitions to exhaustion per set and total in flat bench press (70% 1RM, 6 sets, 1-min interval)
Key secondary outcomes
Subjective Muscle Soreness (Visual Analogue Scale: VAS, 0-100 mm)
Muscle soreness and fatigue levels evaluated at immediately post-exercise, 24h, 48h, and 72h post-exercise for specified anatomical sites (chest, anterior shoulder, posterior upper arm, buttocks, posterior thigh, medial thigh, anterior thigh, and whole body).
Base
Study type
Interventional
Study design
Basic design
Cross-over
Randomization
Randomized
Randomization unit
Individual
Blinding
Double blind -all involved are blinded
Control
Placebo
Stratification
NO
Dynamic allocation
NO
Institution consideration
Institution is not considered as adjustment factor.
Blocking
Concealment
No need to know
Intervention
No. of arms
3
Purpose of intervention
Educational,Counseling,Training
Type of intervention
| Food |
Interventions/Control_1
Test Food A (Low-dose combination): Single ingestion of 100 mL beverage containing low doses of L-arginine and L-citrulline 60 minutes prior to exercise. Washout period is at least 7 days.
Interventions/Control_2
Test Food B (High-dose combination): Single ingestion of 100 mL beverage containing high doses of L-arginine and L-citrulline 60 minutes prior to exercise. Washout period is at least 7 days.
Interventions/Control_3
Test Food C (Placebo control)**: Single ingestion of 100 mL beverage matching test foods A and B in appearance and flavor but without L-arginine or L-citrulline, 60 minutes prior to exercise. Washout period is at least 7 days.
Interventions/Control_4
Interventions/Control_5
Interventions/Control_6
Interventions/Control_7
Interventions/Control_8
Interventions/Control_9
Interventions/Control_10
Eligibility
Age-lower limit
| 18 | years-old | <= |
Age-upper limit
| Not applicable |
Gender
Male
Key inclusion criteria
1) Male athletes / volleyball players belonging to a University Men's Volleyball Club or equivalent.
2) Able to comply with and complete all study protocols and scheduled visits.
3) Provided written informed consent after receiving and fully understanding explanations of the study.
Key exclusion criteria
1) Medical history or current presence of severe cardiac, hepatic, renal, or gastrointestinal diseases.
2) Surgical operations within 6 months prior to consent that may affect study outcomes (e.g., colonoscopic surgery, cholecystectomy).
3) Known allergy to study foods or ingredients.
4) Deemed unsuitable for participation by the principal or co-investigator.
Target sample size
30
Research contact person
Name of lead principal investigator
| 1st name | Manabu |
| Middle name | |
| Last name | Nakata |
Organization
Juntendo University
Division name
Graduate School of Health and Sports Science
Zip code
2701695
Address
1-1 Hirakagakendai, Inzai, Chiba, Japan
TEL
+81-476-98-1001
m-nakata@juntendo.ac.jp
Public contact
Name of contact person
| 1st name | Yoshio |
| Middle name | |
| Last name | Suzuki |
Organization
Juntendo University
Division name
Graduate School of Health and Sports Science
Zip code
2701695
Address
1-1 Hirakagakuendai, Inzai, Chiba, Japan
TEL
+81-476-98-1001
Homepage URL
yssuzuki@juntendo.ac.jp
Sponsor or person
Institute
Juntendo University
Institute
Department
Personal name
Funding Source
Organization
Kowa Company, Ltd.
Organization
Division
Category of Funding Organization
Profit organization
Nationality of Funding Organization
Other related organizations
Co-sponsor
Name of secondary funder(s)
IRB Contact (For public release)
Organization
Ethics Committee of the Juntendo University Faculty and Graduate School of Health and Sports Science
Address
1-1 Hiraka Gakuendai, Inzai, Chiba 270-1695, Japan
Tel
+81-476-1001
sc-gradkyomu@juntendo.ac.jp
Secondary IDs
Secondary IDs
NO
Study ID_1
Org. issuing International ID_1
Study ID_2
Org. issuing International ID_2
IND to MHLW
Institutions
Institutions
Other administrative information
Date of disclosure of the study information
| 2026 | Year | 10 | Month | 07 | Day |
Related information
URL releasing protocol
Publication of results
Unpublished
Result
URL related to results and publications
Number of participants that the trial has enrolled
26
Results
Results date posted
Results Delayed
Results Delay Reason
Date of the first journal publication of results
Baseline Characteristics
Participant flow
Adverse events
Outcome measures
Plan to share IPD
IPD sharing Plan description
Progress
Recruitment status
No longer recruiting
Date of protocol fixation
| 2026 | Year | 05 | Month | 07 | Day |
Date of IRB
| 2026 | Year | 05 | Month | 07 | Day |
Anticipated trial start date
| 2026 | Year | 08 | Month | 01 | Day |
Last follow-up date
| 2026 | Year | 10 | Month | 15 | Day |
Date of closure to data entry
Date trial data considered complete
Date analysis concluded
Other
Other related information
Management information
Registered date
| 2026 | Year | 10 | Month | 07 | Day |
Last modified on
| 2026 | Year | 10 | Month | 07 | Day |
Link to view the page
Value
https://center6.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000072340
