Effect of Citrulline Malate Supplementation on Physical Function and Biochemical Parameters in Physically Active Older Women

NCT07143305 | Completed

• 1 other identifier: CITMAL
• Study Type: interventional
• Target: 20
• Locations: 1 country
• Sites: 1

Brief Summary

A randomised, double-blind, placebo-controlled pilot trial was conducted with thirty-three community-dwelling women aged 65 years or over. Participants were assigned to a multicomponent training programme (three days per week) and received either 3 g per day of citrulline malate or a placebo. Assessments were conducted before and after the intervention, including tests of physical performance (6MWT, sit-to-stand, SPPB), blood biomarkers (vitamin D, glucose, CK, hormones), and perceived quality of life (WHOQOL-BREF).

Conditions

Supplementation

Keywords

citrulline; Physical Performance; older women

Outcome Measures

Primary Outcomes (12)

• Handgrip strength

  Handgrip strength (kg) was assessed with a digital handheld dynamometer (JAMAR®, 0-90 kg; Performance Health, Warrenville, IL, USA), by standardised procedures.

  At baseline, immediately before the start of the supplementation protocol, and at the end of the six-week intervention period, within 24 hours of the final exercise session

• Cardiorespiratory

  Cardiorespiratory fitness was evaluated using the six-minute walk test (6MWT) on a standardised indoor 400-metre track.

  At baseline, immediately before the start of the supplementation protocol, and at the end of the six-week intervention period, within 24 hours of the final exercise session

• Gait speed

  Gait speed was measured over four metres using photoelectric timing gates. Participants began walking five metres before the start line to ensure a consistent pace throughout the timed section.

  At baseline, immediately before the start of the supplementation protocol, and at the end of the six-week intervention period, within 24 hours of the final exercise session

• Lower limb strength

  Lower limb strength was assessed using the Five Times Sit-to-Stand Test (5xSTS), which involved recording the time taken to rise from a 45 cm highchair five times as quickly as possible without using the arms for support.

  At baseline, immediately before the start of the supplementation protocol, and at the end of the six-week intervention period, within 24 hours of the final exercise session

• Balance

  Balance was assessed via static balance testing in three different stances, held for 10 seconds each: side-by-side, semi-tandem and tandem

  At baseline, immediately before the start of the supplementation protocol, and at the end of the six-week intervention period, within 24 hours of the final exercise session

• Frailty and global physical function

  Frailty and global physical function were evaluated using the Short Physical Performance Battery (SPPB), which incorporates tests of gait speed, balance, and the ability to rise from a chair. Based on the total score obtained in all tests (range from 0 to 10), participants are identified as having severe limitations (0-4), moderate limitations (4-6), mild limitations (7-9) and minimal limitations (10-12).

  At baseline, immediately before the start of the supplementation protocol, and at the end of the six-week intervention period, within 24 hours of the final exercise session

• High-density lipoprotein (HDL)

  High-density lipoprotein (HDL) was evaluated to explore potential cardiovascular implications. Venous blood samples were collected under standardised conditions between 08:00 and 08:30 a.m., following a minimum of 12 hours' fasting and at least eight hours' rest overnight. All extractions were performed by a certified nurse at an accredited clinical laboratory (Det Norske Veritas, certification no. 18031, Spain). A total of 10 ml of serum was drawn into clot-activator tubes, centrifuged and stored at -20 °C until analysis. Meanwhile, 3-5 mL of plasma was collected in EDTA® tubes and refrigerated at 4 °C for subsequent processing. All analytical procedures were conducted using standardised and validated platforms. Haematological assessments were performed using the Coulter Counter MAX-M® system, while biochemical and hormonal analyses were conducted using the Architect 2000® analyser (Abbott Diagnostics).

  At baseline, immediately before the start of the supplementation protocol, and at the end of the six-week intervention period, within 24 hours of the final exercise session

• Creatine kinase

  Creatine kinase was measured as an indicator of muscle damage. Venous blood samples were collected under standardised conditions between 08:00 and 08:30 a.m., following a minimum of 12 hours' fasting and at least eight hours' rest overnight. All extractions were performed by a certified nurse at an accredited clinical laboratory (Det Norske Veritas, certification no. 18031, Spain). A total of 10 ml of serum was drawn into clot-activator tubes, centrifuged and stored at -20 °C until analysis. Meanwhile, 3-5 mL of plasma was collected in EDTA® tubes and refrigerated at 4 °C for subsequent processing. All analytical procedures were conducted using standardised and validated platforms. Haematological assessments were performed using the Coulter Counter MAX-M® system, while biochemical and hormonal analyses were conducted using the Architect 2000® analyser (Abbott Diagnostics).

  At baseline, immediately before the start of the supplementation protocol, and at the end of the six-week intervention period, within 24 hours of the final exercise session

• Liver enzyme activity

  Liver enzyme activity was assessed via serum levels of aspartate aminotransferase (AST/GOT) and alanine aminotransferase (ALT/GPT). Venous blood samples were collected under standardised conditions between 08:00 and 08:30 a.m., following a minimum of 12 hours' fasting and at least eight hours' rest overnight. All extractions were performed by a certified nurse at an accredited clinical laboratory (Det Norske Veritas, certification no. 18031, Spain). A total of 10 ml of serum was drawn into clot-activator tubes, centrifuged and stored at -20 °C until analysis. Meanwhile, 3-5 mL of plasma was collected in EDTA® tubes and refrigerated at 4 °C for subsequent processing. All analytical procedures were conducted using standardised and validated platforms. Haematological assessments were performed using the Coulter Counter MAX-M® system, while biochemical and hormonal analyses were conducted using the Architect 2000® analyser (Abbott Diagnostics).

  At baseline, immediately before the start of the supplementation protocol, and at the end of the six-week intervention period, within 24 hours of the final exercise session

• Low-density lipoprotein (LDL)

  Low-density lipoprotein (HDL) was evaluated to explore potential cardiovascular implications. Venous blood samples were collected under standardised conditions between 08:00 and 08:30 a.m., following a minimum of 12 hours' fasting and at least eight hours' rest overnight. All extractions were performed by a certified nurse at an accredited clinical laboratory (Det Norske Veritas, certification no. 18031, Spain). A total of 10 ml of serum was drawn into clot-activator tubes, centrifuged and stored at -20 °C until analysis. Meanwhile, 3-5 mL of plasma was collected in EDTA® tubes and refrigerated at 4 °C for subsequent processing. All analytical procedures were conducted using standardised and validated platforms. Haematological assessments were performed using the Coulter Counter MAX-M® system, while biochemical and hormonal analyses were conducted using the Architect 2000® analyser (Abbott Diagnostics).

  At baseline, immediately before the start of the supplementation protocol, and at the end of the six-week intervention period, within 24 hours of the final exercise session

• Glucose

  Glucose provided insight into metabolic regulation. Venous blood samples were collected under standardised conditions between 08:00 and 08:30 a.m., following a minimum of 12 hours' fasting and at least eight hours' rest overnight. All extractions were performed by a certified nurse at an accredited clinical laboratory (Det Norske Veritas, certification no. 18031, Spain). A total of 10 ml of serum was drawn into clot-activator tubes, centrifuged and stored at -20 °C until analysis. Meanwhile, 3-5 mL of plasma was collected in EDTA® tubes and refrigerated at 4 °C for subsequent processing. All analytical procedures were conducted using standardised and validated platforms. Haematological assessments were performed using the Coulter Counter MAX-M® system, while biochemical and hormonal analyses were conducted using the Architect 2000® analyser (Abbott Diagnostics).

  At baseline, immediately before the start of the supplementation protocol, and at the end of the six-week intervention period, within 24 hours of the final exercise session

• Testosterone

  Testosterone was used to evaluate the hormonal status and potential anabolic-catabolic shifts. Venous blood samples were collected under standardised conditions between 08:00 and 08:30 a.m., following a minimum of 12 hours' fasting and at least eight hours' rest overnight. All extractions were performed by a certified nurse at an accredited clinical laboratory (Det Norske Veritas, certification no. 18031, Spain). A total of 10 ml of serum was drawn into clot-activator tubes, centrifuged and stored at -20 °C until analysis. Meanwhile, 3-5 mL of plasma was collected in EDTA® tubes and refrigerated at 4 °C for subsequent processing. All analytical procedures were conducted using standardised and validated platforms. Haematological assessments were performed using the Coulter Counter MAX-M® system, while biochemical and hormonal analyses were conducted using the Architect 2000® analyser (Abbott Diagnostics).

  At baseline, immediately before the start of the supplementation protocol, and at the end of the six-week intervention period, within 24 hours of the final exercise session

Secondary Outcomes (1)

• Quality of life questionnaire

  At baseline, immediately before the start of the supplementation protocol, and at the end of the six-week intervention period, within 24 hours of the final exercise session

Study Arms (2)

Placebo

ACTIVE COMPARATOR

Placebo supplementation with 3 g/day of maltodextrine

Other: Multicomponent physical exercise programme

Supplementation

EXPERIMENTAL

3 g/day of citrulline malate

Other: Multicomponent physical exercise programme

Interventions

Multicomponent physical exercise programme OTHER

Participants engaged in a multicomponent physical exercise programme designed specifically for older adults. The programme was based on the latest evidence and international recommendations for sarcopenia and functional maintenance in ageing population.

Placebo; Supplementation

Eligibility Criteria

• Age: 60 Years - 75 Years
• Gender Eligibility Details: Identified as women
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Sex: women.
• Age: 60-75 years.

You may not qualify if:

• Functional limitations (Barthel Index \<100 and/or Lawton-Brody Scale \<8).
• Musculoskeletal injuries within the past six months.
• Cardiovascular disease (e.g. advanced heart failure, unstable angina, recent myocardial infarction, arrhythmias, uncontrolled hypertension or hypotension, aortic stenosis, thromboembolic events).
• Respiratory disorders (e.g. chronic respiratory failure or a moderate/severe BODEx index).
• Endocrine/metabolic diseases (e.g. uncontrolled diabetes).
• Neurological or psychiatric disorders (e.g. dementia).
• Prior use of ergogenic nutritional supplements.
• Any other condition deemed incompatible with moderate physical activity by the clinical team.

Sponsors & Collaborators

• Universidad de Burgos: lead

Study Sites (1)

City Council of Soria

Soria, Spain

Location

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: QUADRUPLE
• Who Masked: PARTICIPANT, CARE PROVIDER, INVESTIGATOR, OUTCOMES ASSESSOR
• Purpose: PREVENTION
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Principal Investigator

Study Record Dates

• First Submitted: August 8, 2025
• First Posted: August 27, 2025
• Study Start: March 15, 2020
• Primary Completion: April 15, 2020
• Study Completion: May 15, 2020
• Last Updated: October 2, 2025

Record last verified: 2025-08

Data Sharing

• IPD Sharing: Will not share

Locations

ES (1)