Dietary Nitrate Supplementation and Crossfit Athletes

Performance Clinical Trial

Official title:

The Effects of Six-day Dietary Nitrate Supplementation on Strength and Endurance Measurements in Male CrossFit Athletes

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT02162927
• Other study ID #: HSC2014
• Status: Completed
• Phase: N/A
• First received: June 9, 2014
• Last updated: March 2, 2015
• Start date: August 2014
• Est. completion date: November 2014

Study information

• Verified date: March 2015
• Source: Florida State University
• Contact: n/a
• Is FDA regulated: No
• Health authority: United States: Institutional Review Board
• Study type: Interventional

Clinical Trial Summary

In the past, dietary nitrate supplementation has been shown to have clinical benefits in the treatment of cardiovascular issues. More recently, however, the focus of nitrate supplementation has shifted to focus of human performance, and has shown to increase the time to exhaustion during maximal intensity exercise and lower the cost of oxygen consumption during submaximal intensity exercise. Acutely, nitrate supplementation in the form of beetroot juice has been shown to increase strength measurements, as well as increase the time to complete a 2000 meter rowing ergometer test. However, to the author's knowledge, there are no studies that link the relationship between multi-day nitrate supplementation and the rowing test or the nitrate's effect on strength when in the salt form. Additionally, to the author's knowledge, no evidence has been published which relates dietary nitrate supplementation and its effects on a CrossFit circuit workout.

Our central hypothesis is that six days of dietary nitrate supplementation will improve strength, endurance, a power more than a placebo in male CrossFit athletes.

Description:

The purpose of this randomized, double-blind, crossover study is to identify if dietary nitrate supplementation improves strength , endurance, and power measurements in male CrossFit athletes. Specifically, the strength measurements will be taken using isometric and isokinetic tests on the Biodex dynamometer. Endurance will be measured using time trials for a 2000 meter rowing test and the "Fran" CrossFit workout. Finally, power will be analyzed using the Wingate cycle test.

The treatment group will receive 1 serving of f potassium nitrate KNO3- (N) (8 mmols NO3-). The placebo group will receive 1 serving of the nitrate-free placebo (PL) potassium chloride (8 mmol KCl).

The participants will complete two three-day baseline testing, with a six-day supplementation period following each round of baseline testing. Following the first six-day supplementation period, there will be a 10 day washout period before the second baseline testing begins.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 12
• Est. completion date: November 2014
• Est. primary completion date: October 2014
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: Male
• Age group: 20 Years to 35 Years

Eligibility

Inclusion Criteria:

• College-aged male CrossFit between the ages of 20 and 35 years (yr), a peak maximum oxygen uptake (VO2peak) of at least 50 ml/kg/min will be recruited to participate in this study.

Exclusion Criteria:

• Having any thyroid and/or kidney diseases that could affect NO synthesis and/or metabolism, any illness, smoking, taking other medications, injured, not well-trained (as noted by the VO2peak), consuming any other supplements at the time of the study except protein or multivitamin, allergic to any component of the supplement, including tree nuts, in case of potential packaging mixing and contamination. Women and children as well are excluded.

Study Design

Allocation: Randomized, Intervention Model: Crossover Assignment, Masking: Double Blind (Subject, Investigator), Primary Purpose: Treatment

Related Conditions & MeSH terms

• Performance

Intervention

Dietary Supplement:
• Dietary Nitrate
This pill must be taken on an empty stomach (2-3 hours after eating) and must be taken about 2-3 hours before exercise.
• Potassium Chloride (placebo)
This pill must be taken on an empty stomach (2-3 hours after eating) and must be taken about 2-3 hours before exercise.

Locations

Country	Name	City	State
United States	CrossFit Blackbox	Tallahassee	Florida
United States	Florida State University	Tallahassee	Florida

Sponsors (1)

Lead Sponsor	Collaborator
Florida State University

Country where clinical trial is conducted

United States, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Muscular Strength	Muscular Strength will be tested using the isometric and isokinetic strength tests.	During 1 month of study	No
Primary	Muscular Endurance	Endurance will be tested using the 2000 meter rowing ergometer test and CrossFit circuit known as "Fran".	1 month	No
Primary	Muscular Power	Power will be measured using the Wingate cycle test.	1 month	No