Sodium Bicarbonate Supplementation in Athletes

The Effect of Sodium Bicarbonate Supplementation on Physical Capacity and Body Composition in Trained Athletes

The purpose of this study was to verify the effect of 10-day sodium bicarbonate (NaHCO3) and placebo (PLA) supplementation on body composition, physical capacity, as well as concentrations of the selected biochemical blood markers in trained athletes, in a randomised, double-blind, placebo-controlled crossover trial.

Study Overview

• Status: Completed
• Conditions: Supplementation; Sport
• Intervention / Treatment: Dietary supplement: Sodium bicarbonate supplementation; Dietary supplement: Placebo treatment

Detailed Description

Sodium bicarbonate (NaHCO3) was proposed as an ergogenic agent, because it improves high-intensity and resistance exercise performance. Until now the major limitation to NaHCO3 supplementation has been the gastrointestinal (GI) side effects. Therefore, this study aims to examine the effect of chronic, progressive- dose NaHCO3 ingestion on physical capacity, body composition and concentrations of the selected biochemical blood markers in trained athletes, in a randomised, double-blind, placebo-controlled crossover trial.

• Study Type: Interventional
• Enrollment (Actual): 26
• Phase: Phase 3

Contacts and Locations

Study Locations

• Poland
  • Wielkopolska
    • Poznań, Wielkopolska, Poland, 60-624
      • Poznan University of Life Sciences, ul.Wojska Polskiego 31

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 41 years (Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• written consent to participate,
• a current medical clearance to practice sports,
• training experience: at least 2 years (of CrossFit training),
• minimum of 3 workout sessions (CrossFit) a week,
• 20-43 years.

Exclusion Criteria:

• current injury,
• any health-related contraindication,
• declared general feeling of being unwell,
• unwilling to follow the study protocol.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Triple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Sodium bicarbonate; Group taking oral NaHCO3 supplementation in a progressive-dose regimen. Interventions: The experimental procedure for each athlete included a 10-day NaHCO3 supplementation in a progressive-dose regimen in order to reduce the likelihood of gastrointestinal side effects (from 37.5 to 150 mg ∙ kg-1). NaHCO3 was administered in the form of unmarked disk-shaped tablets (Alkala T, SANUM, Poland). The tablets were ingested with at least 250 mL of water and could be either swallowed or dissolved in the mouth. On training days the supplements were taken in the morning, in the evening and 1.5 hours before training session. On rest days the supplements were taken in the morning, in the afternoon and in the evening. Between the 10-day NaHCO3 and PLA or a PLA and NaHCO3 treatments, a 14-day washout period was introduced.	Dietary supplement: Sodium bicarbonate supplementation
Placebo Comparator: Placebo (maltodextrin); Group taking oral supplementation with placebo (maltodextrin). Interventions: The experimental procedure for each athlete included a 10-day placebo administration. Placebo was ingested with at least 250 mL of water. On training days the supplements were taken in the morning, in the evening and 1.5 hours before training session. On rest days the supplements were taken in the morning, in the afternoon and in the evening. Between the 10-day NaHCO3 and PLA or a PLA and NaHCO3 treatments, a 14-day washout period was introduced.	Dietary supplement: Placebo treatment

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Changes in aerobic capacity after sodium bicarbonate supplementation	The incremental cycling test (ICT)	Baseline and after 10 days
Changes in specific performance capacity after sodium bicarbonate supplementation	The CrossFit-specific physical fitness test: Fight Gone Bad (FGB)	Baseline and after 10 days

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Changes in fat mass and fat free mass after sodium bicarbonate supplementation	Fat mass (kg) and fat free mass (kg) analysis	Baseline and after 10 days
Changes of red and white blood cell concentration in blood after sodium bicarbonate supplementation	Red blood cells (RBC) [mln/mm³] and white blood cells (WBC) [mln/mm³] concentration analysis	Baseline and after 10 days
Changes in blood glucose and hemoglobin concentration after sodium bicarbonate supplementation	Hemoglobin (Hb) [g/dl] and glucose [g/dl] concentration analysis	Baseline and after 10 days
Changes in blood hematocrit levels after sodium bicarbonate supplementation	Hematocrit (HCT) [%] level analysis	Baseline and after 10 days
Changes of lactate and pyruvate concentration in blood after sodium bicarbonate supplementation	Lactate [mmol/L] and pyruvate [mmol/L] concentration analysis	Baseline and after 10 days
Changes of creatine kinase and lactate dehydrogenase activity in blood after sodium bicarbonate supplementation	Creatine kinase [U/L] and lactate dehydrogenase [U/L] activity analysis	Baseline and after 10 days

Collaborators and Investigators

• Sponsor: Poznan University of Life Sciences
• Collaborators: Poznan University of PhysED
• Investigators: Study Chair: Jan Jeszka, Professor, Department of Hygiene and Human Nutrition, Poznan University of Life Sciences, Poznan, Poland

Study record dates

Study Major Dates

• Study Start (Actual): October 10, 2015
• Primary Completion (Actual): March 10, 2016
• Study Completion (Actual): April 5, 2016

Study Registration Dates

• First Submitted: May 22, 2017
• First Submitted That Met QC Criteria: May 23, 2017
• First Posted (Actual): May 24, 2017

Study Record Updates

• Last Update Posted (Actual): May 24, 2017
• Last Update Submitted That Met QC Criteria: May 23, 2017
• Last Verified: May 1, 2017

More Information

Terms related to this study

• Keywords: Physical capacity; Sodium bicarbonate; Crossfit
• Other Study ID Numbers: ULS00002

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: Undecided
• IPD Plan Description: Shared data will be exclusively related to the level recorded indicators (body composition, aerobic and anaerobic capacity indicators, levels of biochemical markers), without personal data. The data obtained will be attached to scientific publications, depending on the requirements of the journal