SupplementationPhase 3NCT07730606
Acute Sodium Bicarbonate Supplementation in Female Basketball Players
A Phase 3 study testing Sodium Bicarbonate (NaHCO3) in people with Supplementation and Sports, run by Krzysztof Durkalec-Michalski at 1 site in Poland.
Trial 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. Read more about this study
- Who is it for?
- Ages 16 to 35 years, women onlyHealthy volunteers can take part
- Conditions the study is for
- Supplementation, Sports
- What is being tested?
- Sodium Bicarbonate (NaHCO3)
- Type of treatment
- Pill or oral medicine
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 100 participants
- Where
- 1 sitePoland
- Study dates
- 1 Mar 2026to 1 Dec 2027
- Phase
- Phase 3
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 16 to 35 years
- Women only
- Healthy volunteers accepted
- Child, Adult
Who may be able to join
- 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,
Show all 9Show fewer
- 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.
Who cannot join
- 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.
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Poland1 site, 1 recruiting
- Recruiting
Department of Sports Dietetics, Poznan University of Physical Education Poznań
Poznan, 61-871
Jakub Adamczewski, MSc, +48 66 317 56 06, adamczewski@awf.poznan.pl
Krzysztof Durkalec-Michalski, PhD, durkalec-michalski@awf.poznan.pl
About this study
Official title: Evaluation of the Effect of Acute Sodium Bicarbonate Supplementation on Physical Capacity and Blood Biochemical Marker Concentrations in Highly Trained Female Basketball Players
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.
Read the detailed description
Sodium bicarbonate (SB) is commonly proposed as an ergogenic aid due to its potential to enhance extracellular buffering capacity, thereby supporting acid-base balance and delaying fatigue during repeated high-intensity exercise. This mechanism may be particularly relevant in basketball, where performance depends on repeated short-duration, high-intensity efforts, rapid recovery between actions, and the ability to maintain power output during demanding phases of play. Although the ergogenic effects of SB supplementation have been widely investigated, existing evidence has primarily focused on male participants, and data regarding highly trained female athletes remain limited. This creates an important knowledge gap, especially in team sports such as basketball, where sex-specific physiological responses, training status, and sport-specific demands may influence the effectiveness and tolerability of supplementation strategies. This study will evaluate the effect of a single dose of SB compared with placebo. Participants will receive SB or placebo in a randomized, double-blind, placebo-controlled crossover design. The SB dose will be 0.3 g/kg body mass, administered 90 minutes before the exercise protocol, with intervention visits separated by a washout period. By using a randomized, double-blind, placebo-controlled crossover design, this study will allow for the evaluation of individual responses to acute SB supplementation under controlled laboratory conditions. The findings may help clarify whether acute SB intake is an effective and tolerable strategy for supporting physical capacity and biochemical responses in highly trained female basketball players.
- Conditions
- Supplementation, Sports
- Being tested
- Sodium Bicarbonate (NaHCO3), Placebo
- 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
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
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.
PlaceboOther
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.
| Study group | Role | What they receive |
|---|---|---|
| Sodium bicarbonate | Experimental | Not described Receives: Dietary Supplement: Sodium Bicarbonate (NaHCO3) |
| PLA treatment | Placebo comparator | Not described Receives: Other: Placebo |
What is being measured
The primary outcome is the main question the study is designed to answer.
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)
Measured: 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)
Measured: 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)
Measured: 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)
Measured: 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)
Measured: 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).
Measured: 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)
Measured: 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)
Measured: 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)
Measured: 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
Assessment of oxygen uptake (VO₂), carbon dioxide production (VCO₂), and minute ventilation (VE) [L/min] during the repeated modified Wingate Anaerobic Test using the K5 wearable metabolic system (Cosmed, Italy)
Measured: 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
Assessment of relative oxygen uptake (VO₂), and carbon dioxide production (VCO₂) [mL/kg/min] during the repeated modified Wingate Anaerobic Test using the K5 wearable metabolic system (Cosmed, Italy)
Measured: 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
Assessment of respiratory exchange ratio (RER) [ratio] during the repeated modified Wingate Anaerobic Test using the K5 wearable metabolic system (Cosmed, Italy)
Measured: 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
Assessment of breathing frequency (BF) [breaths/min] during the repeated modified Wingate Anaerobic Test using the K5 wearable metabolic system (Cosmed, Italy)
Measured: 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
Assessment of tidal volume (VT) [L] during the repeated modified Wingate Anaerobic Test using the K5 wearable metabolic system (Cosmed, Italy)
Measured: At the Day 0 (familiarization visit), Day 7 (baseline visit), Day 14 (experimental visit 1), and Day 21 (experimental visit 2)
Changes in heart rate during the exercise protocol
Assessment of maximum heart rate (HRmax) and mean heart rate (HRmean) [bpm] during the exercise protocol using the HRM-Dual heart rate monitor (Garmin Ltd., United States)
Measured: At the Day 0 (familiarization visit), Day 7 (baseline visit), Day 14 (experimental visit 1), and Day 21 (experimental visit 2)
Changes in rate of perceived exertion
Assessment of rate of perceived exertion (RPE) [Borg scale points] using the 15 point Borg scale, ranging from 6 to 20 points
Measured: At the Day 0 (familiarization visit), Day 7 (baseline visit), Day 14 (experimental visit 1), and Day 21 (experimental visit 2)
Changes in gastrointestinal symptoms
Assessment of gastrointestinal symptoms (GI) [NRS points] using a 19 item gastrointestinal symptom questionnaire with an 11 point numerical rating scale, ranging from 0 to 10 points
Measured: At the Day 0 (familiarization visit), Day 7 (baseline visit), Day 14 (experimental visit 1), and Day 21 (experimental visit 2)
Changes in body mass, fat-free mass, fat mass, total body water, intracellular water, and extracellular water
Assessment of body mass, fat-free mass, fat mass, total body water, intracellular water, and extracellular water [kg (kilograms)] using the WPT 60/150 OW scale with integrated stadiometer (Radwag, Poland) and the 101 BIVA PRO body composition analyzer (Akern S.r.l., Italy)
Measured: At the Day 0 (familiarization visit), Day 7 (baseline visit), Day 14 (experimental visit 1), and Day 21 (experimental visit 2)
Changes in fat-free mass percentage, fat mass percentage, total body water percentage, intracellular water percentage, and extracellular water percentage
Assessment of fat-free mass percentage, fat mass percentage, total body water percentage, intracellular water percentage, and extracellular water percentage [% (percent)] using the 101 BIVA PRO body composition analyzer (Akern S.r.l., Italy)
Measured: At the Day 0 (familiarization visit), Day 7 (baseline visit), Day 14 (experimental visit 1), and Day 21 (experimental visit 2)
Changes in white blood cell count, white blood cell subpopulations, red blood cell count, and platelet count
Assessment of white blood cell count, white blood cell subpopulations, red blood cell count, and platelet count [count/L] in capillary blood using the Mythic 18 hematology analyzer (Orphée, Switzerland)
Measured: At the Day 0 (familiarization visit), Day 7 (baseline visit), Day 14 (experimental visit 1), and Day 21 (experimental visit 2)
Changes in hemoglobin concentration
Assessment of hemoglobin concentration [mmol/L] in capillary blood using the Mythic 18 hematology analyzer (Orphée, Switzerland)
Measured: At the Day 0 (familiarization visit), Day 7 (baseline visit), Day 14 (experimental visit 1), and Day 21 (experimental visit 2)
Changes in hematocrit
Assessment of hematocrit [L/L] in capillary blood using the Mythic 18 hematology analyzer (Orphée, Switzerland)
Measured: At the Day 0 (familiarization visit), Day 7 (baseline visit), Day 14 (experimental visit 1), and Day 21 (experimental visit 2)
Changes in alanine aminotransferase, aspartate aminotransferase, creatine kinase, and lactate dehydrogenase activities
Assessment of alanine aminotransferase (ALAT), aspartate aminotransferase (ASAT), creatine kinase (CK), and lactate dehydrogenase (LDH) activities [U/L] in capillary blood using the ACCENT-220S biochemical analyzer (PZ Cormay S.A., Poland).
Measured: At the Day 0 (familiarization visit), Day 7 (baseline visit), Day 14 (experimental visit 1), and Day 21 (experimental visit 2)
Changes in creatinine concentration
Assessment of creatinine concentration [µmol/L] in capillary blood using the ACCENT-220S biochemical analyzer (PZ Cormay S.A., Poland).
Measured: At the Day 0 (familiarization visit), Day 7 (baseline visit), Day 14 (experimental visit 1), and Day 21 (experimental visit 2)
Changes in urea concentration
Assessment of urea concentration [mmol/L] in capillary blood using the ACCENT-220S biochemical analyzer (PZ Cormay S.A., Poland).
Measured: At the Day 0 (familiarization visit), Day 7 (baseline visit), Day 14 (experimental visit 1), and Day 21 (experimental visit 2)
Changes in iron, unsaturated iron-binding capacity, and total iron-binding capacity concentrations
Assessment of iron, unsaturated iron-binding capacity (UIBC), and total iron-binding capacity (TIBC) concentrations [µg/dL] in capillary blood using the ACCENT-220S biochemical analyzer (PZ Cormay S.A., Poland).
Measured: At the Day 0 (familiarization visit), Day 7 (baseline visit), Day 14 (experimental visit 1), and Day 21 (experimental visit 2)
Changes in ferritin concentration
Assessment of ferritin concentration [ng/mL] in capillary blood using the ACCENT-220S biochemical analyzer (PZ Cormay S.A., Poland).
Measured: At the Day 0 (familiarization visit), Day 7 (baseline visit), Day 14 (experimental visit 1), and Day 21 (experimental visit 2)
Changes in transferrin concentration
Assessment of transferrin concentration [g/L] in capillary blood using the ACCENT-220S biochemical analyzer (PZ Cormay S.A., Poland).
Measured: At the Day 0 (familiarization visit), Day 7 (baseline visit), Day 14 (experimental visit 1), and Day 21 (experimental visit 2)
Changes in partial pressure of carbon dioxide and oxygen
Assessment of partial pressure of carbon dioxide (pCO₂) and partial pressure of oxygen (pO₂) [mmHg] in capillary blood using the ABL90 FLEX PLUS blood gas analyzer (Radiometer, Denmark).
Measured: At the Day 0 (familiarization visit), Day 7 (baseline visit), Day 14 (experimental visit 1), and Day 21 (experimental visit 2)
Changes in oxygen saturation and hemoglobin fractions
Assessment of oxygen saturation (sO₂), oxyhemoglobin fraction (FO₂Hb), carboxyhemoglobin fraction (FCOHb), deoxyhemoglobin fraction (FHHb), and methemoglobin fraction (FMetHb) [% (percent)] in capillary blood using the ABL90 FLEX PLUS blood gas analyzer (Radiometer, Denmark).
Measured: At the Day 0 (familiarization visit), Day 7 (baseline visit), Day 14 (experimental visit 1), and Day 21 (experimental visit 2)
Changes in potassium, sodium, ionized calcium, and chloride concentration
Assessment of potassium (K⁺), sodium (Na⁺), ionized calcium (Ca²⁺), and chloride (Cl-) concentrations [mmol/L] in capillary blood using the ABL90 FLEX PLUS blood gas analyzer (Radiometer, Denmark).
Measured: At the Day 0 (familiarization visit), Day 7 (baseline visit), Day 14 (experimental visit 1), and Day 21 (experimental visit 2)
Changes in plasma osmolality
Assessment of plasma osmolality [mOsm/kg] in capillary blood using the ABL90 FLEX PLUS blood gas analyzer (Radiometer, Denmark).
Measured: At the Day 0 (familiarization visit), Day 7 (baseline visit), Day 14 (experimental visit 1), and Day 21 (experimental visit 2)
Changes in dietary energy intake
Assessment of dietary energy intake [kcal] based on 48 hour dietary records analyzed using AvoDiet dietary software (JustForFood sp. z o.o., Poland).
Measured: At the Day 0 (familiarization visit), Day 7 (baseline visit), Day 14 (experimental visit 1), and Day 21 (experimental visit 2)
Changes in dietary macronutrient intake
Assessment of protein, carbohydrate, fat, and dietary fiber intake [g (grams)] based on 48 hour dietary records analyzed using AvoDiet dietary software (JustForFood sp. z o.o., Poland).
Measured: At the Day 0 (familiarization visit), Day 7 (baseline visit), Day 14 (experimental visit 1), and Day 21 (experimental visit 2)
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted28 Jul 2026
- Study start1 Mar 2026
- Primary completion1 Dec 2027 (estimated)
- Study completion1 Dec 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for SupplementationStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 3
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- Quadruple blind
- Who is masked
- Participant, Care provider, Investigator, Outcomes assessor
- Enrolment
- 100 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Krzysztof Durkalec-Michalski
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor-investigator, Krzysztof Durkalec-Michalski, Poznan University of Physical Education
- Investigators
- Krzysztof Durkalec-Michalski, PhD, Study chair, Department of Sports Dietetics, Poznan University of Physical Education, Poznan, Poland
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07730606
- Sponsor's protocol ID
- ZDS_2026_1
- Status last verified
- Jul 2026
- First submitted
- 5 Jul 2026
- Last updated
- 28 Jul 2026
- Results posted
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Undecided: Shared data will be exclusively related to the level of recorded indicators, without personal data. The data obtained will be attached to scientific publications, depending on the requirements of the journal.
Study at a glance
From the registry record, last updated by the sponsor on 28 Jul 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Evaluation of the Effect of Acute Sodium Bicarbonate Supplementation on Physical Capacity and Blood Biochemical Marker Concentrations in Highly Trained Female Basketball Players
- ClinicalTrials.gov ID
- NCT07730606
- Acronym / sponsor ID
- ZDS_2026_1
- Conditions
- Supplementation, Sports
- Keywords
- Acid-base balance, Acute supplementation, Anaerobic performance, Basketball, Blood biochemical markers, Ergogenic aids, Female athletes, Gastrointestinal symptoms
- Phase
- Phase 3
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 100 participants (estimated)
- Lead sponsor
- Krzysztof Durkalec-MichalskiUniversity, hospital or other
- Study start
- 1 Mar 2026 (actual)
- Primary completion
- 1 Dec 2027 (estimated)
- Study completion
- 1 Dec 2027 (estimated)
- First posted
- 28 Jul 2026 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
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.
Detailed description
Sodium bicarbonate (SB) is commonly proposed as an ergogenic aid due to its potential to enhance extracellular buffering capacity, thereby supporting acid-base balance and delaying fatigue during repeated high-intensity exercise. This mechanism may be particularly relevant in basketball, where performance depends on repeated short-duration, high-intensity efforts, rapid recovery between actions, and the ability to maintain power output during demanding phases of play. Although the ergogenic effects of SB supplementation have been widely investigated, existing evidence has primarily focused on male participants, and data regarding highly trained female athletes remain limited. This creates an important knowledge gap, especially in team sports such as basketball, where sex-specific physiological responses, training status, and sport-specific demands may influence the effectiveness and tolerability of supplementation strategies. This study will evaluate the effect of a single dose of SB compared with placebo. Participants will receive SB or placebo in a randomized, double-blind, placebo-controlled crossover design. The SB dose will be 0.3 g/kg body mass, administered 90 minutes before the exercise protocol, with intervention visits separated by a washout period. By using a randomized, double-blind, placebo-controlled crossover design, this study will allow for the evaluation of individual responses to acute SB supplementation under controlled laboratory conditions. The findings may help clarify whether acute SB intake is an effective and tolerable strategy for supporting physical capacity and biochemical responses in highly trained female basketball players.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- Quadruple blind (participant, care provider, investigator, outcomes assessor)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Sodium bicarbonate | Experimental | Dietary Supplement: Sodium Bicarbonate (NaHCO3) |
| PLA treatment | Placebo comparator | Other: Placebo |
Who may qualify
- Ages
- 16 to 35 years
- Sex
- Female only
- Healthy volunteers
- Accepted
- Age groups
- Child, Adult
Key inclusion criteria (9 listed)
- 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,
Key exclusion criteria (6 listed)
- 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,
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Sodium Bicarbonate (NaHCO3)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. | Dietary supplement | Sodium bicarbonate |
| PlaceboParticipants 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. | Other | PLA treatment |
Primary outcome
Changes in anaerobic power during the repeated modified Wingate Anaerobic Test
Time frame: At the Day 0 (familiarization visit), Day 7 (baseline visit), Day 14 (experimental visit 1), and Day 21 (experimental visit 2)
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)
Changes in interval mean power during the repeated modified Wingate Anaerobic Test
Time frame: At the Day 0 (familiarization visit), Day 7 (baseline visit), Day 14 (experimental visit 1), and Day 21 (experimental visit 2)
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)
Changes in second-by-second power output during the repeated modified Wingate Anaerobic Test
Time frame: At the Day 0 (familiarization visit), Day 7 (baseline visit), Day 14 (experimental visit 1), and Day 21 (experimental visit 2)
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)
Changes in time to peak power during the repeated modified Wingate Anaerobic Test
Time frame: At the Day 0 (familiarization visit), Day 7 (baseline visit), Day 14 (experimental visit 1), and Day 21 (experimental visit 2)
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)
Changes in countermovement jump height
Time frame: At the Day 0 (familiarization visit), Day 7 (baseline visit), Day 14 (experimental visit 1), and Day 21 (experimental visit 2)
Assessment of countermovement jump (CMJ) height [cm (centimeters)] during three consecutive CMJ attempts using the OptoJump Next optical measurement system (Microgate, Italy)
Changes in countermovement jump power
Time frame: At the Day 0 (familiarization visit), Day 7 (baseline visit), Day 14 (experimental visit 1), and Day 21 (experimental visit 2)
Assessment of countermovement jump (CMJ) power [W (watts)] during three consecutive CMJ attempts using the OptoJump Next optical measurement system (Microgate, Italy).
Changes in blood bicarbonate, base excess, anion gap, and lactate concentrations
Time frame: At the Day 0 (familiarization visit), Day 7 (baseline visit), Day 14 (experimental visit 1), and Day 21 (experimental visit 2)
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)
Changes in hydrogen ion concentration
Time frame: At the Day 0 (familiarization visit), Day 7 (baseline visit), Day 14 (experimental visit 1), and Day 21 (experimental visit 2)
Assessment of hydrogen ion concentration [nmol/L] in capillary blood using the ABL90 FLEX PLUS blood gas analyzer (Radiometer, Denmark)
Changes in pH in blood
Time frame: At the Day 0 (familiarization visit), Day 7 (baseline visit), Day 14 (experimental visit 1), and Day 21 (experimental visit 2)
Assessment of blood pH [pH units] in capillary blood using the ABL90 FLEX PLUS blood gas analyzer (Radiometer, Denmark)
25 secondary outcomes
Changes in oxygen uptake, carbon dioxide production, and minute ventilation during the repeated modified Wingate Anaerobic Test
Time frame: 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
Time frame: 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
Time frame: 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
Time frame: 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
Time frame: At the Day 0 (familiarization visit), Day 7 (baseline visit), Day 14 (experimental visit 1), and Day 21 (experimental visit 2)
Changes in heart rate during the exercise protocol
Time frame: At the Day 0 (familiarization visit), Day 7 (baseline visit), Day 14 (experimental visit 1), and Day 21 (experimental visit 2)
Changes in rate of perceived exertion
Time frame: At the Day 0 (familiarization visit), Day 7 (baseline visit), Day 14 (experimental visit 1), and Day 21 (experimental visit 2)
Changes in gastrointestinal symptoms
Time frame: At the Day 0 (familiarization visit), Day 7 (baseline visit), Day 14 (experimental visit 1), and Day 21 (experimental visit 2)
Changes in body mass, fat-free mass, fat mass, total body water, intracellular water, and extracellular water
Time frame: At the Day 0 (familiarization visit), Day 7 (baseline visit), Day 14 (experimental visit 1), and Day 21 (experimental visit 2)
Changes in fat-free mass percentage, fat mass percentage, total body water percentage, intracellular water percentage, and extracellular water percentage
Time frame: At the Day 0 (familiarization visit), Day 7 (baseline visit), Day 14 (experimental visit 1), and Day 21 (experimental visit 2)
Changes in white blood cell count, white blood cell subpopulations, red blood cell count, and platelet count
Time frame: At the Day 0 (familiarization visit), Day 7 (baseline visit), Day 14 (experimental visit 1), and Day 21 (experimental visit 2)
Changes in hemoglobin concentration
Time frame: At the Day 0 (familiarization visit), Day 7 (baseline visit), Day 14 (experimental visit 1), and Day 21 (experimental visit 2)
Changes in hematocrit
Time frame: At the Day 0 (familiarization visit), Day 7 (baseline visit), Day 14 (experimental visit 1), and Day 21 (experimental visit 2)
Changes in alanine aminotransferase, aspartate aminotransferase, creatine kinase, and lactate dehydrogenase activities
Time frame: At the Day 0 (familiarization visit), Day 7 (baseline visit), Day 14 (experimental visit 1), and Day 21 (experimental visit 2)
Changes in creatinine concentration
Time frame: At the Day 0 (familiarization visit), Day 7 (baseline visit), Day 14 (experimental visit 1), and Day 21 (experimental visit 2)
Changes in urea concentration
Time frame: At the Day 0 (familiarization visit), Day 7 (baseline visit), Day 14 (experimental visit 1), and Day 21 (experimental visit 2)
Changes in iron, unsaturated iron-binding capacity, and total iron-binding capacity concentrations
Time frame: At the Day 0 (familiarization visit), Day 7 (baseline visit), Day 14 (experimental visit 1), and Day 21 (experimental visit 2)
Changes in ferritin concentration
Time frame: At the Day 0 (familiarization visit), Day 7 (baseline visit), Day 14 (experimental visit 1), and Day 21 (experimental visit 2)
Changes in transferrin concentration
Time frame: At the Day 0 (familiarization visit), Day 7 (baseline visit), Day 14 (experimental visit 1), and Day 21 (experimental visit 2)
Changes in partial pressure of carbon dioxide and oxygen
Time frame: At the Day 0 (familiarization visit), Day 7 (baseline visit), Day 14 (experimental visit 1), and Day 21 (experimental visit 2)
Changes in oxygen saturation and hemoglobin fractions
Time frame: At the Day 0 (familiarization visit), Day 7 (baseline visit), Day 14 (experimental visit 1), and Day 21 (experimental visit 2)
Changes in potassium, sodium, ionized calcium, and chloride concentration
Time frame: At the Day 0 (familiarization visit), Day 7 (baseline visit), Day 14 (experimental visit 1), and Day 21 (experimental visit 2)
Changes in plasma osmolality
Time frame: At the Day 0 (familiarization visit), Day 7 (baseline visit), Day 14 (experimental visit 1), and Day 21 (experimental visit 2)
Changes in dietary energy intake
Time frame: At the Day 0 (familiarization visit), Day 7 (baseline visit), Day 14 (experimental visit 1), and Day 21 (experimental visit 2)
Changes in dietary macronutrient intake
Time frame: At the Day 0 (familiarization visit), Day 7 (baseline visit), Day 14 (experimental visit 1), and Day 21 (experimental visit 2)
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 28 Jul 2026.
- Individual participant dataSharing planned: Undecided. Shared data will be exclusively related to the level of recorded indicators, without personal data. The data obtained will be attached to scientific publications, depending on the requirements of the journal.
Related trials for Supplementation
Recruiting
Micronutrient Supplementation and Chronotherapy in Children With ADHD
Attention Deficit Hyperactivity Disorder (ADHD)
Recruiting
Effects of Red Panax Ginseng Supplementation on Cognitive Performance and Emotional Well-Being in Young Healthy Adults
Mental Acuity
Not yet recruiting
Efficacy of Carnitine Complex in Improving Hepatic Steatosis in Potential Liver Donors
Hepatic Steatosis, Fatty Liver
RecruitingPhase 2
FAST for DM - Fatty Acid Supplementation Trial (FAST) for Dermatomyositis (DM)
Dermatomyositis (DM), Juvenile Dermatomyositis (JDM)
Enrolling by invitation
Effect of Omega-3 Supplementation on Pregnant Outcomes and Inflammation Markers of Women Infected With HIV Using Antiretroviral Therapy
Pregnant HIV Positive Women
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
Krzysztof Durkalec-Michalski, PhD study chair
Department of Sports Dietetics, Poznan University of Physical Education, Poznan, Poland
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 3 study testing Sodium Bicarbonate (NaHCO3) in people with Supplementation and Sports, run by Krzysztof Durkalec-Michalski at 1 site in Poland.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 9 inclusion and 6 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 28 Jul 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Poland. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. Some participants in this study may receive a placebo. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 3 studies compare the treatment with the current standard treatment or a placebo in a large group, to confirm how well it works and watch for side effects.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Jakub Adamczewski, MSc (+48 66 317 56 06, adamczewski@awf.poznan.pl), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Changes in anaerobic power during the repeated modified Wingate Anaerobic Test (time frame: At the Day 0 (familiarization visit), Day 7 (baseline visit), Day 14 (experimental visit 1), and Day 21 (experimental visit 2)). The study lists 9 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 28 Jul 2026.