Influence of Sodium Bicarbonate on Time-to-exhaustion at Critical Power in Endurance Athletes

During endurance exercise in the heavy and severe intensity domains, the rate at which metabolites that have been associated with the fatigue process (e.g. Pi, ADP, H, and extracellular K) accumulate increases. possibly leading to exercise cessation. Sodium bicarbonate, as a nutritional supplement, has gained attention over the past decades, because it might delay of offset fatigue. To date, there is a controversial discussion about which delivery mode (amount and frequency) might be best in optimizing endurance performance. Since the high ion load consequent to multiple ingestions might increase plasma volume, and consequently decrease bicarbonate concentrations, single acute ingestion could be more beneficial. However, in multi-day competitions or tournaments it might be necessary to use the supplement on a daily basis. Here, the investigators aim at investigating the effects of single dose or multiple dose (on five consecutive days) administration of bicarbonate vs. placebo increases endurance performance and acid-base homeostasis in trained male endurance athletes.

Study Overview

• Status: Completed
• Conditions: Performance
• Intervention / Treatment: Dietary supplement: Sodium bicarbonate; Dietary supplement: Placebo

• Study Type: Interventional
• Enrollment (Actual): 12
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Switzerland
  • ZH
    • Zurich, ZH, Switzerland, 8091
      • University Hospital Zurich, Division of Neurology

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 45 years (ADULT)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: Male

Description

Inclusion criteria: - male

• no cold or temperature at beginning or during the study
• between 18 and 45 years of age
• active in endurance sports (3 to 5 times per week a moderate to hart training)
• non-smoker
• no known cardiovascular or orthopedic problems
• no known limitations of kidney function
• no bearer of a cardiac pacemaker
• no medications with direct influence on the measurements. The whole intake of medicaments has to be declared in the health questionnaire by the participant.
• requirements of the health questionnaire fulfilled

Exclusion criteria: - female

• male and age under 18 or over 45 years
• cold or temperature at the beginning or during the study
• untrained (less than 3 moderate trainings per week)
• smoker
• cardiovascular or orthopedic problems
• limitations of the kidney function
• bearer of a cardiac pacemaker
• medication with direct influence on the measurements. The whole intake of medicaments has to be declared in the health questionnaire by the participant.
• requirements of the health questionnaire not fulfilled

Study Plan

How is the study designed?

Design Details

• Allocation: RANDOMIZED
• Interventional Model: CROSSOVER
• Masking: DOUBLE

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
PLACEBO_COMPARATOR: Placebo	Dietary supplement: Placebo; Placebo effect
ACTIVE_COMPARATOR: Sodium bicarbonate	Dietary supplement: Sodium bicarbonate; Ergogenic effect

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Time-to-exhaustion	5 weeks

Collaborators and Investigators

• Sponsor: University of Zurich
• Collaborators: Swiss Federal Institute of Technology
• Investigators: Study Director: Neurologie: Neurologische Forschung, University Hospital Zurich, Division of Neurology; Principal Investigator: Marco Toigo, PhD, Swiss Federal Institute of Technology Zurich

Publications and helpful links

General Publications

• Mueller SM, Gehrig SM, Frese S, Wagner CA, Boutellier U, Toigo M. Multiday acute sodium bicarbonate intake improves endurance capacity and reduces acidosis in men. J Int Soc Sports Nutr. 2013 Mar 26;10(1):16. doi: 10.1186/1550-2783-10-16.

Study record dates

Study Major Dates

• Study Start: October 1, 2011
• Primary Completion (ACTUAL): August 1, 2012
• Study Completion (ACTUAL): January 1, 2013

Study Registration Dates

• First Submitted: June 12, 2012
• First Submitted That Met QC Criteria: June 14, 2012
• First Posted (ESTIMATE): June 15, 2012

Study Record Updates

• Last Update Posted (ESTIMATE): April 12, 2013
• Last Update Submitted That Met QC Criteria: April 11, 2013
• Last Verified: April 1, 2013

More Information

Terms related to this study

• Other Study ID Numbers: nbc