The Impact of Omega-3 Fatty Acid Supplementation on the Composition of Erythrocyte Membranes in Athletes (OMEGA-PERFORM)

August 14, 2026 updated by: Małgorzata Magdalena Michalczyk, The Jerzy Kukuczka Academy of Physical Education in Katowice

Effects of Omega-3 Fatty Acid Supplementation on Omega-3 Index, Cognitive Function, Hormonal Profile, Speed, and Endurance in Competitive Athletes Aged 16-35 Years: A Randomized Placebo-Controlled Trial

The aim of this study is to evaluate the effects of omega-3 fatty acid supplementation on the Omega-3 Index, erythrocyte membrane composition, cognitive function, hormonal profile, speed, endurance performance, and hematological parameters in competitive athletes aged 16-35 years.

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Recruiting

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Detailed Description

Skeletal muscle function, including the ability to generate force, sustain repeated high-intensity efforts, and resist fatigue, is essential for soccer performance. In addition to neuromuscular adaptations, increasing evidence suggests that nutritional interventions, particularly omega-3 fatty acid supplementation, may influence muscle function, recovery, inflammation, and cognitive performance. However, despite growing interest in omega-3 fatty acids, evidence regarding their effects on physical and cognitive performance in competitive soccer players remains limited.

The present randomized, placebo-controlled trial aims to evaluate the effects of four weeks of high-dose omega-3 fatty acid supplementation in competitive male soccer players aged 16 to 35 years. Participants will continue their regular soccer training and maintain their habitual mixed diet throughout the study.

The primary objective is to determine the effects of supplementation on the Omega-3 Index and the erythrocyte fatty acid profile, including omega-3, omega-6, trans fatty acids, and arachidonic acid (AA). In addition, the study will evaluate changes in cognitive function, hormonal profile, speed and endurance performance, hematological parameters, lipid profile, inflammatory markers, oxidative-antioxidant status, and erythrocyte membrane composition.

The fatty acid profile will be assessed using a validated laboratory method that enables quantitative determination of individual fatty acids in erythrocyte membranes, providing an objective biomarker of long-term omega-3 status and membrane lipid composition. This approach allows comprehensive evaluation of the biological response to omega-3 supplementation in competitive athletes.

The findings of this study are expected to improve understanding of the physiological effects of high-dose omega-3 fatty acid supplementation in soccer players and may contribute to evidence-based nutritional strategies aimed at optimizing health, recovery, cognitive function, and athletic performance.

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Interventional

Enrollment (Estimated)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
200

Phase

Phase

The stage of a clinical trial studying a drug or biological product, based on definitions developed by the U.S. Food and Drug Administration (FDA). The phase is based on the study's objective, the number of participants, and other characteristics. There are five phases: Early Phase 1 (formerly listed as Phase 0), Phase 1, Phase 2, Phase 3, and Phase 4. Not Applicable is used to describe trials without FDA-defined phases, including trials of devices or behavioral interventions.
  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact

The name and contact information for the person who can answer enrollment questions for a clinical study. Each location where the study is being conducted may also have a specific contact, who may be better able to answer those questions.

Study Contact Backup

Study Locations

  • Poland
    • Mikolowska 72a
      • Katowice, Mikolowska 72a, Poland, 40-065
        • Recruiting
        • Jerzy Kukuczka Academy of Physical Education in Katowice
        • Contact:
        • Contact:

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

  • Child
  • Adult

Accepts Healthy Volunteers

Yes

Description

**Inclusion Criteria:**

  • Male competitive soccer players aged 16-35 years.
  • Regular participation in organized soccer training and competition.
  • A minimum of 6 years of systematic soccer training experience.
  • Participation in regular team training during the study period.
  • Habitual mixed diet.
  • Ability and willingness to maintain usual dietary habits and training load throughout the 4-week intervention.
  • Written informed consent provided by the participant.
  • For participants under 18 years of age, written informed consent provided by a parent or legal guardian and assent provided by the participant.

**Exclusion Criteria:**

  • Current use of omega-3 fatty acid supplements or fish-oil products.
  • Use of omega-3 supplements within the 3 months preceding enrollment.
  • Known allergy or hypersensitivity to fish, seafood, fish oil, or any ingredient of the study supplements.
  • Diagnosed cardiovascular, metabolic, endocrine, gastrointestinal, neurological, inflammatory, autoimmune, or hematological disease.
  • Acute infection, injury, or illness that could affect participation in training or study assessments.
  • Use of medications or dietary supplements that could influence lipid metabolism, inflammatory status, hormonal profile, blood coagulation, cognitive function, or physical performance.
  • Regular use of anticoagulant or antiplatelet medication.
  • Significant change in diet, training volume, or supplementation during the study period.
  • Failure to comply with the supplementation protocol or attendance requirements.
  • Participation in another clinical or nutritional intervention study during the study period.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Diagnostic
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Double

Arms and Interventions

Participant Group / Arm

Participant Group / Arm

A group or subgroup of participants in a clinical trial that receives a specific intervention/treatment, or no intervention, according to the trial's protocol.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
Experimental: Omega-3 fatty acid supplementation group
Participants will received 3.5g EPA+ DHA for 4 weeks
Dietary supplement: EPA + DHA supplements
Participants will randomly assigned to the supplemented group. The supplement will be administered in a dose of 4 capsules twice a day for 4 weeks. Daily dose will contain 3500mg EPA + DHA
Placebo Comparator: Placebo group
Participants will received 3.5g placebo for 4 weeks
Dietary supplement: Placebo
Participants will randomly assigned to the Placebo group. The placebo will be administered in a dose of 4 capsules twice a day for 4 weeks. Daily dose will contain 3500mg MCT.

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Measure Description
Time Frame
Change in Omega Index
Time Frame: From enrollment to the end of 4-week supplementation
The Omega-3 Index will be assessed in erythrocytes as the combined percentage of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) relative to total fatty acids in erythrocyte membranes. Blood samples will be collected at baseline and after the 4-week supplementation period. In addition to the Omega-3 Index, the erythrocyte fatty acid profile, including individual omega-3 and omega-6 fatty acids, arachidonic acid (AA), and trans fatty acids, will be assessed. Changes from baseline to the end of the 4-week intervention will be evaluated.
From enrollment to the end of 4-week supplementation

Secondary Outcome Measures

Secondary Outcome Measures

In a clinical study's protocol, a planned outcome measure that is not as important as the primary outcome measure for evaluating the effect of an intervention but is still of interest. Most clinical studies have more than one secondary outcome measure.
Outcome Measure
Measure Description
Time Frame
Neuromuscular function
Time Frame: From enrollment to the end of supplementation period of 4 weeks
Neuromuscular function was assessed using tensiomyography (TMG), a non-invasive method for evaluating the contractile properties of skeletal muscles. Parameters including contraction time (Tc), delay time (Td), sustain time (Ts), relaxation time (Tr), and maximal radial displacement (Dm) were measured at baseline and after the 4-week intervention.
From enrollment to the end of supplementation period of 4 weeks
Hematological parameters and hormones
Time Frame: From enrollment to the end of supplementation period of 4 weeks
Hematological parameters were assessed using fasting venous blood samples. Outcome measures included complete blood count variables, including red blood cell count, white blood cell count, hemoglobin, hematocrit, platelet count, and red blood cell indices. Also testosteron and cortisol concentration was measured. Changes from baseline to the end of the 4-week intervention were evaluated.
From enrollment to the end of supplementation period of 4 weeks
Lipoprteine profile
Time Frame: From enrollment to the end of supplementation period of 4 weeks
The lipoprotein profile was assessed using fasting blood samples. Outcome measures included total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, and triglycerides. Changes from baseline to the end of the 4-week intervention were evaluated.
From enrollment to the end of supplementation period of 4 weeks
Cognitive function
Time Frame: From enrollment to the end of supplementation period of 4 weeks
Cognitive function was assessed using the Corsi Block-Tapping Test, which evaluates visuospatial working memory, short-term memory capacity, and executive cognitive performance. Changes in test performance were compared between baseline and the end of the 4-week intervention.
From enrollment to the end of supplementation period of 4 weeks
Speed on 5 and 30m
Time Frame: From enrollment to the end of supplementation period of 4 weeks
Running times will be recorded using two pairs of dual-beam Witty Gate photocells (Microgate, Bolzano, Italy), a valid and reliable system for sprint performance assessment. Following a standardized warm-up, participants will perform two maximal 30-m sprint trials on an indoor artificial grass surface, with 15 minutes of passive recovery between trials. To prevent premature activation of the timing system, participants will start with the leading foot positioned 0.5 m behind the first timing gate. Split times at 5 m and 30 m will be recorded automatically, and the best performance from the two trials will be used for statistical analysis.
From enrollment to the end of supplementation period of 4 weeks
Anaerobic performance
Time Frame: From enrollment to the end of supplementation period of 4 weeks
Anaerobic performance will be assessed using the Running-Based Anaerobic Sprint Test (RAST). Following a standardized warm-up, participants will perform six maximal 35-m sprints separated by 10 seconds of passive recovery. Sprint times will be recorded using an electronic timing system. Peak power, mean power, minimum power, fatigue index, and total sprint time will be calculated according to the standard RAST protocol. All tests will be performed under standardized environmental conditions, and participants will receive standardized verbal encouragement throughout the test.
From enrollment to the end of supplementation period of 4 weeks
CMJ performance
Time Frame: From enrollment to the end of 4-week supplementation

Countermovement jump performance will be assessed using dual force plates (ForceDecks, VALD Performance, Australia), a validated system for quantifying vertical jump kinetics and kinematics. Before testing, participants will stand quietly on the force plates for 3 seconds to determine body mass and baseline force.

The testing protocol will include bilateral countermovement jumps with arm swing (CMJa) and unilateral countermovement jumps performed separately on the dominant and non-dominant limbs. Participants will perform a rapid countermovement followed immediately by a maximal vertical jump. Three maximal trials will be completed for each test, with 1 minute of passive recovery between bilateral trials and 30 seconds between unilateral trials. The best trial for each test will be retained for analysis.

Vertical ground reaction force data will be sampled at 1000 Hz and analyzed using the manufacturer's software. Outcome measures will incl
From enrollment to the end of 4-week supplementation
Change in Reactive Strength and Leg Stiffness
Time Frame: From enrollment to the end of 4-week supplementation
Reactive strength and lower-limb stiffness will be assessed using the Myotest Pro system during three consecutive maximal plyometric jumps. Outcome measures will include reactive strength index (RSI) and leg stiffness. Changes from baseline to the end of the 4-week intervention will be evaluated.
From enrollment to the end of 4-week supplementation

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
The Jerzy Kukuczka Academy of Physical Education in Katowice

Investigators

Investigators

A researcher involved in a clinical study. Related terms include site principal investigator, site sub-investigator, study chair, study director, and study principal investigator.
  • Study Director: Małgorzata M Michalczyk, Proffesor, Institute of Sport Sciences, Jerzy Kukuczka Academy of Physical Education in Katowice

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
January 7, 2025

Primary Completion (Actual)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
February 14, 2025

Study Completion (Estimated)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
December 31, 2028

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
August 7, 2026

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
August 14, 2026

First Posted (Actual)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
August 17, 2026

Study Record Updates

Last Update Posted (Actual)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
August 17, 2026

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
August 14, 2026

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
August 1, 2026

More Information

Terms related to this study

Keywords

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • 4-I/2024 (Other Grant/Funding Number: The Jerzy Kukuczka Academy of Physical Education in Katowice)

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

YES

IPD Plan Description

Anonymised data will be available upon reasonable request.

IPD Sharing Supporting Information Type

  • STUDY_PROTOCOL

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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