Dietary Nitrate Supplementation and Crossfit Athletes

Florida State University

Status: Completed

Conditions: Performance

Treatments: Dietary Supplement: Potassium Chloride (placebo); Dietary Supplement: Dietary Nitrate

Study type: Interventional

Funder types: Other

Identifiers

NCT02162927

HSC2014

Details and patient eligibility

About

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.

Full 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.

Enrollment: 12 patients

Sex: Male

Ages: 20 to 35 years old

Volunteers: Accepts Healthy Volunteers

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.

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Crossover Assignment

Masking: Double Blind

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12 participants in 2 patient groups, including a placebo group

Potassium Nitrate (N)

Experimental group

Description:

This involves 1 serving (2 pills) of potassium nitrate KNO3- (N) (8 mmols NO3-). The supplementation period is six days. This pill must be taken on an empty stomach (2-3 hours after eating) and must be taken about 2-3 hours before exercise.

Treatment:

Dietary Supplement: Dietary Nitrate

Potassium Chloride

Placebo Comparator group

Description:

This involves 1 serving (2 pills) of the nitrate-free placebo (PL) potassium chloride (8 mmol KCl) for a six-day supplementation period. This pill must be taken on an empty stomach (2-3 hours after eating) and must be taken about 2-3 hours before exercise.

Treatment:

Dietary Supplement: Potassium Chloride (placebo)