Acute Sodium Bicarbonate Supplementation in Female Basketball Players

NCT07730606 | Recruiting Phase 3

• 1 other identifier: ZDS_2026_1
• Study Type: interventional
• Target: 100
• Locations: 1 country
• Sites: 1

Brief Summary

This randomized, double-blind, placebo-controlled crossover study aims to evaluate the effect of acute sodium bicarbonate supplementation, compared with placebo, on physical capacity and blood biochemical marker concentrations in highly trained female basketball players.

Conditions

Supplementation; Sports

Keywords

Acid-base balance; Acute supplementation; Anaerobic performance; Basketball; Blood biochemical markers; Ergogenic aids; Female athletes; Gastrointestinal symptoms; Physical capacity; Sodium bicarbonate; Sports nutrition; Team sports

Outcome Measures

Primary Outcomes (9)

• Changes in anaerobic power during the repeated modified Wingate Anaerobic Test

  Assessment of peak power (PP), average power (AP), minimum power (MP), and power drop (PD) \[W (watts)\] during the repeated modified Wingate Anaerobic Test using the Monark 894E cycle ergometer (Monark, Sweden)

  At the Day 0 (familiarization visit), Day 7 (baseline visit), Day 14 (experimental visit 1), and Day 21 (experimental visit 2)

• Changes in interval mean power during the repeated modified Wingate Anaerobic Test

  Assessment of mean power \[W (watts)\] in predefined 5 second intervals, including 1 to 5 s and 6 to 10 s, during each 10 second effort of the repeated modified Wingate Anaerobic Test using the Monark 894E cycle ergometer (Monark, Sweden)

  At the Day 0 (familiarization visit), Day 7 (baseline visit), Day 14 (experimental visit 1), and Day 21 (experimental visit 2)

• Changes in second-by-second power output during the repeated modified Wingate Anaerobic Test

  Assessment of power output \[W (watts)\] for each 1 second segment, including 1 s, 2 s, 3 s, 4 s, 5 s, 6 s, 7 s, 8 s, 9 s, and 10 s, during each 10 second effort of the repeated modified Wingate Anaerobic Test using the Monark 894E cycle ergometer (Monark, Sweden)

  At the Day 0 (familiarization visit), Day 7 (baseline visit), Day 14 (experimental visit 1), and Day 21 (experimental visit 2)

• Changes in time to peak power during the repeated modified Wingate Anaerobic Test

  Assessment of time to peak power (TTP) \[s (seconds)\] during each 10 second effort of the repeated modified Wingate Anaerobic Test using the Monark 894E cycle ergometer (Monark, Sweden)

  At the Day 0 (familiarization visit), Day 7 (baseline visit), Day 14 (experimental visit 1), and Day 21 (experimental visit 2)

• Changes in countermovement jump height

  Assessment of countermovement jump (CMJ) height \[cm (centimeters)\] during three consecutive CMJ attempts using the OptoJump Next optical measurement system (Microgate, Italy)

  At the Day 0 (familiarization visit), Day 7 (baseline visit), Day 14 (experimental visit 1), and Day 21 (experimental visit 2)

• Changes in countermovement jump power

  Assessment of countermovement jump (CMJ) power \[W (watts)\] during three consecutive CMJ attempts using the OptoJump Next optical measurement system (Microgate, Italy).

  At the Day 0 (familiarization visit), Day 7 (baseline visit), Day 14 (experimental visit 1), and Day 21 (experimental visit 2)

• Changes in blood bicarbonate, base excess, anion gap, and lactate concentrations

  Assessment of blood bicarbonate, base excess, anion gap, and lactate concentrations \[mmol/L\] in capillary blood using the ABL90 FLEX PLUS blood gas analyzer (Radiometer, Denmark)

  At the Day 0 (familiarization visit), Day 7 (baseline visit), Day 14 (experimental visit 1), and Day 21 (experimental visit 2)

• Changes in hydrogen ion concentration

  Assessment of hydrogen ion concentration \[nmol/L\] in capillary blood using the ABL90 FLEX PLUS blood gas analyzer (Radiometer, Denmark)

  At the Day 0 (familiarization visit), Day 7 (baseline visit), Day 14 (experimental visit 1), and Day 21 (experimental visit 2)

• Changes in pH in blood

  Assessment of blood pH \[pH units\] in capillary blood using the ABL90 FLEX PLUS blood gas analyzer (Radiometer, Denmark)

  At the Day 0 (familiarization visit), Day 7 (baseline visit), Day 14 (experimental visit 1), and Day 21 (experimental visit 2)

Secondary Outcomes (25)

• Changes in oxygen uptake, carbon dioxide production, and minute ventilation during the repeated modified Wingate Anaerobic Test

  At the Day 0 (familiarization visit), Day 7 (baseline visit), Day 14 (experimental visit 1), and Day 21 (experimental visit 2)

• Changes in relative oxygen uptake during the repeated modified Wingate Anaerobic Test

  At the Day 0 (familiarization visit), Day 7 (baseline visit), Day 14 (experimental visit 1), and Day 21 (experimental visit 2)

• Changes in respiratory exchange ratio during the repeated modified Wingate Anaerobic Test

  At the Day 0 (familiarization visit), Day 7 (baseline visit), Day 14 (experimental visit 1), and Day 21 (experimental visit 2)

• Changes in breathing frequency during the repeated modified Wingate Anaerobic Test

  At the Day 0 (familiarization visit), Day 7 (baseline visit), Day 14 (experimental visit 1), and Day 21 (experimental visit 2)

• Changes in tidal volume during the repeated modified Wingate Anaerobic Test

  At the Day 0 (familiarization visit), Day 7 (baseline visit), Day 14 (experimental visit 1), and Day 21 (experimental visit 2)

Study Arms (2)

Sodium bicarbonate

EXPERIMENTAL

Dietary Supplement: Sodium Bicarbonate (NaHCO3)

PLA treatment

PLACEBO COMPARATOR

Other: Placebo

Interventions

Sodium Bicarbonate (NaHCO3) DIETARY_SUPPLEMENT

Sodium bicarbonate supplementation; Participants will receive a single oral dose of sodium bicarbonate (SB) at 0.3 g/kg body mass, administered in opaque gelatin capsules 90 minutes before the exercise protocol during the first intervention visit.

Sodium bicarbonate

Placebo OTHER

Participants will receive a single oral dose of placebo (PL), administered in identical opaque gelatin capsules 90 minutes before the exercise protocol during the first intervention visit.

PLA treatment

Eligibility Criteria

• Age: 16 Years - 35 Years
• Sex: female
• Healthy Volunteers: Yes
• Age Groups: Child (0-17), Adult (18-64)

You may qualify if:

• female sex,
• age 16 to 35 years,
• good general health condition and well-being,
• regular menstrual cycles,
• written informed consent to participate in the study before its commencement,
• at least a high level of training status,
• at least 4 years of training experience in basketball,
• participation in at least 3 basketball-specific training sessions per week,
• participation in at least 1 basketball game per week.

You may not qualify if:

• male sex,
• use of hormonal contraceptives,
• current injury or musculoskeletal condition limiting participation in training or competition,
• health-related or medical contraindications, including menstrual disorders, planned pregnancy, or anemia,
• use of supplements within 3 months before the study, except for regular use of protein supplements, carbohydrate supplements, or isotonic drinks,
• failure to meet the study protocol assumptions or unwillingness to follow study procedures.

Sponsors & Collaborators

• Krzysztof Durkalec-Michalski: lead

Study Sites (1)

Department of Sports Dietetics, Poznan University of Physical Education Poznań

Poznan, 61-871, Poland

RECRUITING

MeSH Terms

Interventions

Sodium Bicarbonate

Intervention Hierarchy (Ancestors)

Bicarbonates; Carbonates; Carbonic Acid; Carbon Compounds, Inorganic; Inorganic Chemicals; Sodium Compounds

Study Officials

• Krzysztof Durkalec-Michalski, PhD

  Department of Sports Dietetics, Poznan University of Physical Education, Poznan, Poland

  STUDY CHAIR

Central Study Contacts

Jakub Adamczewski, MSc

CONTACT

+48 66 317 56 06; adamczewski@awf.poznan.pl

Krzysztof Durkalec-Michalski, PhD

CONTACT

+48 61 835 51 65; durkalec-michalski@awf.poznan.pl

Study Design

• Study Type: interventional
• Phase: phase 3
• Allocation: RANDOMIZED
• Masking: QUADRUPLE
• Who Masked: PARTICIPANT, CARE PROVIDER, INVESTIGATOR, OUTCOMES ASSESSOR
• Purpose: TREATMENT
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: SPONSOR INVESTIGATOR
• PI Title: Prof.

Study Record Dates

• First Submitted: July 5, 2026
• First Posted: July 28, 2026
• Study Start: March 1, 2026
• Primary Completion (Estimated): December 1, 2027
• Study Completion (Estimated): December 1, 2027
• Last Updated: July 28, 2026

Record last verified: 2026-07

Locations

PL (1)