Effects of Sodium Bicarbonate on Endurance Performance

NCT ID: NCT07171047

Last Updated: 2025-09-12

Basic Information

• Recruitment Status: RECRUITING
• Clinical Phase: NA
• Total Enrollment: 15 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2025-09-15
• Study Completion Date: 2026-02-28

Brief Summary

This study is investigating whether taking sodium bicarbonate, a common supplement used by endurance athletes, can improve cycling performance during prolonged exercise and in a time trial. Sodium bicarbonate may help reduce muscle acidity, which could delay fatigue and improve performance. The goal of this study is to determine if this supplement can help athletes perform better during long, intense efforts like those seen in real competitions.

Participants in this study are well-trained cyclists who will complete two exercise trials in a laboratory setting. Each trial involves three hours of moderate cycling followed by a 20-30-minute time trial at maximum effort. Before each trial, participants will take either sodium bicarbonate or a placebo.

The study will measure performance outcomes, such as time trial results, as well as physiological responses, including heart rate, oxygen use, and muscle fatigue. Researchers hope to better understand how sodium bicarbonate can help endurance athletes and provide guidelines for its use in competitive sports.

Conditions

Healthy; Athlete; Well-trained Athletes; Performance

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: CROSSOVER
• Primary Study Purpose: TREATMENT
• Blinding Strategy: DOUBLE

Study Groups

Placebo then Verum

Placebo then Verum 3 hour low-intensity ride followed by a 16 km time trial for both conditions. Supplementation of Placebo or Verum before the exercise start.

Group Type: OTHER

Placebo then Verum

Intervention Type: DIETARY_SUPPLEMENT

Intake of 0.3 g/kg bodyweight of maltodextrin with hydrogel as placebo and 0.3 g/kg bodyweight of sodium bicarbonate with hydrogel as Verum

Verum then Placebo

Verum then Placebo 3 hour low-intensity ride followed by a 16 km time trial for both conditions. Supplementation of Placebo or Verum before the exercise start.

Group Type: OTHER

Verum then Placebo

Intervention Type: DIETARY_SUPPLEMENT

Intake of 0.3 g/kg bodyweight of maltodextrin with hydrogel as placebo and 0.3 g/kg bodyweight of sodium bicarbonate with hydrogel as Verum

Interventions

Placebo then Verum

Intake of 0.3 g/kg bodyweight of maltodextrin with hydrogel as placebo and 0.3 g/kg bodyweight of sodium bicarbonate with hydrogel as Verum

Intervention Type: DIETARY_SUPPLEMENT

Verum then Placebo

Intake of 0.3 g/kg bodyweight of maltodextrin with hydrogel as placebo and 0.3 g/kg bodyweight of sodium bicarbonate with hydrogel as Verum

Intervention Type: DIETARY_SUPPLEMENT

Eligibility Criteria

Inclusion Criteria

• age 16-50 years
• well-trained cyclists
• Proof of physical fitness (e.g. sports medical examination required) for measurements with higher intensities (e.g. endurance tests, competition simulation)
• >10h endurance training per week

Exclusion Criteria

• Systemic disease or other known pathology in the organs: heart, lungs, kidney, stomach, spleen, liver, gall bladder, and intestines.
• Evidence of pulmonary disease: forced expiratory volume in one second/forced expiratory volume < 70% with/without symptoms (cough, sputum) or other evidence of pulmonologic disease.

Diabetes II.

• Minimum Eligible Age: 16 Years
• Maximum Eligible Age: 50 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

Red Bull Athlete Performance Center

UNKNOWN

Sponsor Role: collaborator

University of Salzburg

OTHER

Sponsor Role: lead

Responsible Party

Nils Haller, PhD

Senior Researcher

Responsibility Role: PRINCIPAL_INVESTIGATOR

Locations

Red Bull Athlete Performance Center

Thalgau, Salzburg, Austria

Site Status: RECRUITING

Countries

Austria

Central Contacts

Nils Haller, PD PhD

Role: CONTACT

nils.haller@plus.ac.at

+4961313923587

Tilmann Strepp, Master of Science

Role: CONTACT

tilmann.strepp@redbullperformance.com

Facility Contacts

Tilmann Strepp, Master of Science

Role: primary

tilmann.strepp@redbullperformance.com

+4366488379557

Other Identifiers

BICARB_Haller

Identifier Type: -

Identifier Source: org_study_id