The Effect of Individual Sodium Citrate Consumption on Repeated Sprint Performance in Female Soccer Players

NCT07737327 | Not Yet Recruiting

• 2 other identifiers: SBA 25/791225S791
• Study Type: interventional
• Target: 20
• Locations: 0 countries
• Sites: N/A

Brief Summary

The aim of this research is to determine whether sodium citrate supplementation, taken at the best individual time, would improve repeated sprint performance in professional female soccer players. The main questions it aims to answer are:

1. 1.Does sodium citrate improve sprint times, peak power, minimum power, and mean power during repeated sprints?
2. 2.Does sodium citrate lower fatigue index (the drop in power across sprints) during repeated sprint exercise?
3. 3.Does sodium citrate change blood bicarbonate, pH, and lactate levels before and after exercise?
4. 4.Does sodium citrate affect how hard exercise feels (perceived exertion)?

Conditions

Exercise-Induced Fatigue; Athletic Performance; Soccer

Keywords

Sodium citrate; Buffering agent; Repeated sprint performance; Female athletes; Soccer; Anaerobic performance; Blood bicarbonate; Individualized timing

Outcome Measures

Primary Outcomes (2)

• Minimum Power

  The lowest power output recorded across six maximal 35-meter sprints during the Running-based Anaerobic Sprint Test (RAST). Calculated as body weight (kg) multiplied by the square of sprint distance (m) divided by the cube of the slowest sprint time (s).

  Measured during the RAST test, administered immediately after the individualized ingestion-to-exercise interval (T_peak for sodium citrate; 120-150 minutes post-ingestion for placebo)

• Fatigue Index

  The rate of power decline across six maximal 35-meter sprints during the Running-based Anaerobic Sprint Test (RAST). Calculated as the difference between peak power and minimum power divided by total sprint time (W/s).

  Measured during the RAST test, administered immediately after the individualized ingestion-to-exercise interval (T_peak for sodium citrate; 120-150 minutes post-ingestion for placebo)

Secondary Outcomes (7)

• Peak Power

  Measured during the RAST test, administered immediately after the individualized ingestion-to-exercise interval (T_peak for sodium citrate; 120-150 minutes post-ingestion for placebo)

• Mean Power

  Measured during the RAST test, administered immediately after the individualized ingestion-to-exercise interval (T_peak for sodium citrate; 120-150 minutes post-ingestion for placebo)

• Sprint Times

  Measured during the RAST test, administered immediately after the individualized ingestion-to-exercise interval (T_peak for sodium citrate; 120-150 minutes post-ingestion for placebo)

• Blood Bicarbonate Concentration

  Measured at baseline (pre-ingestion), pre-exercise (at T_peak for sodium citrate; 120-150 minutes post-ingestion for placebo), and at 1, 3, 5, and 7 minutes post-exercise.

• Blood pH

  Measured at baseline (pre-ingestion), pre-exercise (at T_peak for sodium citrate; 120-150 minutes post-ingestion for placebo), and at 1, 3, 5, and 7 minutes post-exercise.

Study Arms (2)

Sodium Citrate

EXPERIMENTAL

Participants will ingest sodium citrate at a dose of 0.5 g/kg body weight dissolved in flavored water. Capillary blood sampling will begin 90 minutes post-ingestion and continue at regular intervals. Exercise will begin when blood bicarbonate concentration reaches its individual peak (T\_peak).

Dietary Supplement: Sodium Citrate Oral Product

Placebo

EXPERIMENTAL

Participants will ingest sodium chloride (NaCl) at a taste-matched dose. Exercise will begin 120-150 minutes post-ingestion, consistent with the expected digestion timeline and the typical T\_peak window observed with sodium citrate supplementation.

Other: Placebo

Interventions

Sodium Citrate Oral Product DIETARY_SUPPLEMENT

0.5 g/kg body weight of sodium citrate dissolved in flavored water, ingested orally. Exercise begins at individual peak blood bicarbonate time (T\_peak), determined through serial capillary blood sampling starting 90 minutes post-ingestion.

Also known as: Trisodium citrate

Sodium Citrate

Placebo OTHER

Sodium chloride (NaCl) at a taste-matched dose dissolved in flavored water, ingested orally. Exercise begins 120-150 minutes post-ingestion.

Also known as: Sodium Chloride, NaCl

Placebo

Eligibility Criteria

• Age: 18 Years - 25 Years
• Gender Eligibility Details: Female only.
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Female professional soccer players competing in the Turkish Women's Third League
• Age between 18-25 years
• Active training status (minimum 3 sessions per week)
• Regular menstrual cycles
• Both experimental trials scheduled in the same phase of the menstrual cycle, outside of menstruation
• No use of nutritional supplements in the 4 weeks prior to the study
• Willingness to provide written informed consent

You may not qualify if:

• Use of oral contraceptives
• Irregular menstrual cycle
• History of gastrointestinal disorders
• Any musculoskeletal injury preventing maximal sprint performance
• Smoking
• Use of any medication that may affect acid-base balance
• Pregnancy

Sponsors & Collaborators

• Hacettepe University: lead

Related Publications (18)

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Related Links

• Related Info

MeSH Terms

Interventions

trisodium citrate; Sodium Chloride

Intervention Hierarchy (Ancestors)

Chlorides; Hydrochloric Acid; Chlorine Compounds; Inorganic Chemicals; Sodium Compounds

Study Officials

• Hüseyin Hüsrev TURNAGÖL, Professor

  Hacettepe University, Faculty of Sport Sciences

  PRINCIPAL INVESTIGATOR

• Muhammed M Atakan, Associate Professor

  Hacettepe University

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Dilara KURU, PhD Candidate

CONTACT

+905317242084; dytdilarakuru@gmail.com

Hüseyin Hüsrev TURNAGÖL, Professor

CONTACT

+905323975259; husrevturnagol@gmail.com

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, INVESTIGATOR
• Masking Details: The lead researcher managed randomization and was not involved in blood sampling or performance testing. Participants and the blood-sampling investigator were blinded to treatment allocation.
• Purpose: BASIC SCIENCE
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Associate Professor

Model Details: Each participant will complete both the sodium citrate and placebo trials in a randomized order, with a washout period of at least three days between trials.

Study Record Dates

• First Submitted: July 27, 2026
• First Posted: July 30, 2026
• Study Start (Estimated): August 20, 2026
• Primary Completion (Estimated): November 30, 2026
• Study Completion (Estimated): February 1, 2027
• Last Updated: July 30, 2026

Record last verified: 2026-07

Data Sharing

• IPD Sharing: Will not share