Fermented Milk Drink With Lacticaseibacillus Paracasei Strain Shirota Helps Triathletes With Cold-Like Symptoms Before and After a Race

NCT06970964 | Completed

• 1 other identifier: 7.349.261
• Study Type: interventional
• Target: 80
• Locations: 1 country
• Sites: 1

Brief Summary

This study aims to evaluate whether a fermented milk drink containing the probiotic strain Lacticaseibacillus paracasei strain Shirota (LCS), commonly found in Yakult®, can help reduce upper respiratory symptoms in triathletes before and after competition. Athletes often experience cold-like symptoms due to physical stress, intense training, and immune system challenges. The study investigates whether daily consumption of this probiotic drink can help improve immune response and reduce the incidence or severity of symptoms such as sore throat, nasal congestion, or coughing. This is a randomized, double-blind, placebo-controlled, parallel-group study involving healthy adult triathletes. Participants will be randomly assigned to receive either the probiotic drink or a placebo for a specific period before and after a triathlon event. Symptoms and health markers will be tracked through questionnaires and biological samples. The goal is to explore whether probiotic supplementation can provide practical, non-pharmacological support for athletes' immune health and well-being during intense physical activity.

Conditions

Systemic Inflammation; Depressive Disorder; Exercise-Induced Immunosuppression; Athletic Performance; Upper Respiratory Tract Symptoms; Mental Health; Cytokine Response; Probiotic Therapy; Respiratory Tract Infections (RTI); Mucosal Immunity

Keywords

Immune Function; Sports Nutrition; Endurance Athletes; Lacticaseibacillus paracasei strain Shirota; Upper Respiratory Symptoms; Respiratory Tract Infections; Immunity; Mucosal; Inflammation; Probiotics; Exercise

Outcome Measures

Primary Outcomes (1)

• Salivary IgA Concentration

  The primary outcome measure is the change in salivary immunoglobulin A (IgA) concentration after daily intake of fermented milk containing Lacticaseibacillus paracasei strain Shirota. Saliva samples will be collected from participants at five time points: 30 days before the competition, 24 hours before, immediately after, 72 hours after, and 14 days post-competition. The concentration of salivary IgA will be measured to assess the impact of probiotic supplementation on immune function.

  Pre-study: 30 days before the competition (baseline) During study: 24 hours before the competition Post-study: Immediately after the competition, 72 hours post-competition, and 14 days after the competition

Secondary Outcomes (1)

• Immune/Inflammatory Response

  Pre-study: 30 days before the competition (baseline) During study: 24 hours before the competition Post-study: Immediately after the competition, 72 hours post-competition, and 14 days after the competition

Other Outcomes (2)

• Upper Airway Symptoms

  Pre-study: 30 days before the competition (baseline) During study: 24 hours before the competition Post-study: Immediately after the competition, 72 hours post-competition, and 14 days after the competition

• Mood State

  Pre-study: 30 days before the competition (baseline) During study: 24 hours before the competition Post-study: Immediately after the competition, 72 hours post-competition, and 14 days after the competition

Study Arms (2)

Probiotic

EXPERIMENTAL

Participants will receive one bottle per day of fermented milk containing 40 billion colony-forming units of Lacticaseibacillus paracasei strain Shirota (LcS) for 44 days.Intervention: Type: Dietary Supplement Name: Lacticaseibacillus paracasei strain Shirota Description: Daily intake of fermented milk containing 40 billion CFU of LcS.

Dietary Supplement: Intervention Name: Fermented milk containing Lacticaseibacillus paracasei strain Shirota. Intervention Name: Non-fermented milk (placebo)

Placebo Group

PLACEBO COMPARATOR

Name: Non-fermented milk Description: Daily intake of placebo (non-fermented milk) matched in appearance and taste to the probiotic.

Dietary Supplement: Non-fermented milk (placebo)

Interventions

Non-fermented milk (placebo) DIETARY_SUPPLEMENT

Participants will ingest 80 mL per day of non-fermented milk identical in taste, appearance, and packaging to the probiotic drink, but without Lacticaseibacillus paracasei strain Shirota. Administration follows the same schedule as the probiotic group.

Also known as: Placebo milk

Placebo Group

Intervention Name: Fermented milk containing Lacticaseibacillus paracasei strain Shirota. Intervention Name: Non-fermented milk (placebo) DIETARY_SUPPLEMENT

Participants will ingest 80 mL per day of fermented milk containing 40 billion colony-forming units (CFU) of Lacticaseibacillus paracasei strain Shirota (LcS), starting 30 days before a triathlon competition and continuing until 14 days post-race. The fermented milk is stored refrigerated and consumed once daily.

Also known as: LcS, Lacticaseibacillus casei Shirota, Probiotic milk drink

Probiotic

Eligibility Criteria

• Age: 25 Years - 45 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Aged between 25 and 45 years.
• Amateur triathletes with regular endurance training and prior competition experience.
• In good general health, with no history of chronic diseases or conditions affecting immune or inflammatory responses.
• Willing and able to comply with all study procedures, including sample collections and completion of validated questionnaires at five time points.
• Agree to consume a daily dose of fermented milk containing Lacticaseibacillus paracasei strain Shirota (LcS) or placebo from 30 days before until 14 days after the competition.
• No use of probiotics, antibiotics, or immunomodulatory supplements in the 30 days prior to enrollment

You may not qualify if:

• Known allergy or intolerance to dairy products, including lactose.
• Use of probiotics or antibiotics within 30 days prior to enrollment.
• Current use of any pharmacological treatment.
• History of chronic rhinopathy.
• Diagnosis of autoimmune disease.
• History of recurrent infections not involving the upper airway.
• Presence of major medical conditions or chronic diseases, including but not limited to respiratory or gastrointestinal disorders.
• Incomplete or missing data necessary for determining eligibility or for study outcomes.

Sponsors & Collaborators

• Federal University of São Paulo: lead

Study Sites (1)

Federal University of Sao Paulo

São Paulo, São Paulo, 04039-032, Brazil

Location

Related Publications (1)

• Vaisberg M, Paixao V, Almeida EB, Santos JMB, Foster R, Rossi M, Pithon-Curi TC, Gorjao R, Momesso CM, Andrade MS, Araujo JR, Garcia MC, Cohen M, Perez EC, Santos-Dias A, Vieira RP, Bachi ALL. Daily Intake of Fermented Milk Containing Lactobacillus casei Shirota (Lcs) Modulates Systemic and Upper Airways Immune/Inflammatory Responses in Marathon Runners. Nutrients. 2019 Jul 22;11(7):1678. doi: 10.3390/nu11071678.

  PMID: 31336570 BACKGROUND

Related Links

• ORL Lab -Official website of the laboratory where the activities will be carried out at the Federal University of Sao Paulo-Brazil
• instagram ORL LAB page

MeSH Terms

Conditions

Respiratory Tract Infections; Depressive Disorder; Psychological Well-Being; Signs and Symptoms, Respiratory; Inflammation; Motor Activity

Condition Hierarchy (Ancestors)

Infections; Respiratory Tract Diseases; Mood Disorders; Mental Disorders; Personal Satisfaction; Behavior; Signs and Symptoms; Pathological Conditions, Signs and Symptoms; Pathologic Processes

Study Officials

• Jonatas B do Amaral, PHD

  Federal University of São Paulo

  PRINCIPAL INVESTIGATOR

• André Luis L Bachi, PHD

  Santo Amaro University

  STUDY CHAIR

• Cesar Miguel M dos Santos, PHD

  Enau College

  STUDY CHAIR

• Mauro W Vaisberg, PHD

  Federal University of São Paulo

  STUDY CHAIR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: QUADRUPLE
• Who Masked: PARTICIPANT, CARE PROVIDER, INVESTIGATOR, OUTCOMES ASSESSOR
• Masking Details: This is a double-blind study. Participants, care providers, investigators, and outcomes assessors will be blinded to group assignments to prevent bias.
• Purpose: PREVENTION
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Principal Investigator

Model Details: Participants will be randomly assigned to one of two parallel groups: one receiving fermented milk containing Lacticaseibacillus paracasei strain Shirota and the other receiving placebo (non-fermented milk).

Study Record Dates

• First Submitted: April 30, 2025
• First Posted: May 14, 2025
• Study Start: August 13, 2025
• Primary Completion: August 21, 2025
• Study Completion: November 5, 2025
• Last Updated: January 15, 2026

Record last verified: 2025-05

Data Sharing

• IPD Sharing: Will share
• Shared Documents: STUDY PROTOCOL, SAP, ICF, CSR, ANALYTIC CODE
• Time Frame: IPD and supporting documents will be available beginning 6 months after publication of the study results and will remain available for 3 years.
• Access Criteria: Researchers who provide a methodologically sound proposal will be able to access the IPD and supporting information. Requests should be directed to the principal investigator by email. A data access agreement will be required prior to sharing.

Locations

BR (1)