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Nitrato: suplementação, fontes dietéticas e efeitos na performance - Nitrate: supplementation, dietary sources and effects on performance.

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O óxido nítrico possui papel importante na regulação de parâmetros funcionais e fisiológicos relacionados ao desempenho esportivo. Recentemente, foi comprovada sua ação vasodilatadora e hipotensiva, bem como no aumento da eficiência energética e na melhora da contração muscular além de conversão de fibras musculares. Sua principal via de formação é dependente das óxido nítrico sintases, enzimas dependentes de oxigênio que, em hipóxia, reduzem sua ação. Nestas situações, o NO é formado a partir do nitrato inorgânico (NO3-) e nitrito provenientes da alimentação. O aumento da ingestão de NO3-, por alimentação ou suplementação, parece promover aumento de desempenho esportivos em diversos tipos de exercício. Entretanto, seu efeito ergogênico é dependente do condicionamento físico, tipo e duração do exercício e da dose administrada. Indivíduos com menor condicionamento físico parecem se beneficiar mais dos efeitos da suplementação que indivíduos treinados. Além disso, a suplementação parece potencializar o desempenho de forma mais consistente frente a exercícios de alta intensidade e curta duração quando comparada com seus efeitos sobre exercícios de endurance.
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Revista Brasileira de
Brazilian Journal of Functional Nutrition
NUTRIÇÃO
FUNCIONAL
ano 17. edição 71
www.vponline.com.br
ISSN 2176-4522
Interpretando a
dosagem da vitamina B12
Nitrato: suplementação,
fontes dietéticas e efeitos na performance
Série Agroecologia: Parte II
A importância das abelhas para a agroecologia
RECEITA
Tortinha de Legumes com
Taioba
2
Revista Brasileira de Nutrição Funcional
Editorial
Nesta nova edição, importantes atualizações cientícas nas áreas de Nutrição Clínica,
Nutrição Esportiva e Fitoterapia contribuirão para a prática clínica de nossos
leitores.
Em Nutrição Esportiva, uma esclarecedora revisão acerca do papel do nitrato
na performance esportiva, proveniente de fontes alimentares ou suplementares,
mostrará ao prossional dessa área que a ação desse componente pode ir além
da vasodilatação: se bem aplicado, pode potencializar o desempenho em exer-
cícios de alta intensidade e curta duração. Ainda sobre nutrição e esporte, uma
atualização sobre o papel da vitamina D no esporte abre evidências de sua atuação
como importante estratégia para o processo de hipertroa muscular.
Em Nutrição Clínica, uma revisão sobre a interpretação da dosagem da vitamina
B12 incita discussões importantes para a prática clínica. A adequada interpretação
das dosagens de vitamina B12 é essencial para os âmbito preventivos e terapêuticos
das doenças correlacionadas à deciência dessa vitamina, prevalente especialmente em alguns grupos
de risco, como crianças, idosos, gestantes e veganos.
Em Fitoterapia, trazemos um estudo de caso com a aplicação clíni-
ca de Astragalus membranaceus, com resultados iniciais interessantes
sobre a modulação do sistema imune.
Na sessão de Gastronomia, uma receita nutritiva, prática e saborosa
que valoriza nossa biodiversidade: tortinha de legumes com taioba.
Dando continuidade à séria sobre Agroecologia, a matéria desta
edição mostra um tema preocupante e de grande relevância, acerca
do risco de extinção das abelhas, que tem como uma das causas o uso
excessivo de agrotóxicos.
Excelente leitura!
Dra. Valéria Paschoal
Diretora da VP Centro de Nutrição Funcional
Dra. Paula Gandin
Presidente do Instuto Brasileiro de Nutrição Funcional
3
www.vponline.com.br
Expediente
Conselho Editorial
Ana Cláudia Poleo
Nutricionista pela Universidade Estadual do Centro-Oeste (2002) e mestre em Ciências, com ênfase em
Fisiologia Humana pela Universidade de São Paulo (2006). Pesquisadora (doutoranda, desde 2007) do
programa de Fisiologia Humana da Universidade de São Paulo. Tem experiência na área de Fisiologia
Endócrina, atuando nos temas: mecanismos transcricionais envolvidos na regulação da expressão do gene
SLC2A4, sensibilidade à insulina, metabolismo lipídico, obesidade e diabetes mellitus.
Ana Vládia Bandeira Moreira
Nutricionista graduada pela Universidade Estadual do Ceará (1996), mestre em Ciências dos Alimentos pela
Universidade de São Paulo (1999) e doutora em Ciências dos Alimentos pela Universidade de São Paulo (2003).
Atualmente é professora adjunta da Universidade Federal de Viçosa (MG). Coordenadora do Laboratório
de Análise de alimentos e coordenadora do Projeto de extensão pró-celíaco. Ministra as disciplinas de

especialização na UFV.
Andréia Naves
Nutricionista e Educadora Física. Diplomada pelo The Instute for Funconal Medicine (USA) em 2007. Editora


Centro de Nutrição Funcional em parceria com a Universidade Cruzeiro do Sul. Autora dos Livros “Nutrição

     
The Instute
for Funconal Medicine
Funcional da VP Centro de Nutrição Funcional em parceria com a Universidade Cruzeiro do Sul.
Revista Brasileira de Nutrição Funcional - 2017 - edição 71
Indexação: Sumários (www.sumarios.org) e ESALQ (hp://dibd.esalq.usp.br)
Diretoras Responsáveis
Valéria Paschoal e Andréia Naves
Coordenação Cientíca
Ana Beatriz Baptistella Leme da Fonseca
consultoriacientica@vponline.com.br
Neiva dos Santos Souza
neiva.souza@vponline.com.br
Jornalista Responsável
José Maria M. Filho
MTB – 19.852 - josemaria@vponline.com.br
Revisão Ortográca
Lemuel Cintra
lcintra@gmail.com
Capa, Ilustrações e Editoração
Bárbara Feracin Meira
Ctp e Impressão
A.R. Fernandez Pré-Impressão e Gráca
www.arfernandez.com.br
comercial@arfernandez.com.br
Redação, Publicidade e Administração
VP Centro de Nutrição Funcional
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contato@vponline.com.br
www.vponline.com.br
Revista Brasileira de
Brazilian Journal of Functional Nutrition
NUTRIÇÃO
FUNCIONAL
ano 17. edição 69
www.vponline.com.br
ISSN 2176-4522
Utilização do ômega-3 na
síntese proteica e recuperação muscular
Impacto ambiental
dos alimentos transgênicos
Série Agroecologia: Parte I -
Conceito e diferentes técnicas de cultivo
RECEITA
Filé de linguado assado
com molho de castanha
e gengibre e purê de
banana-da-terra
capa.indd 1 26/06/2017 12:06:45
Revista Brasileira de
Brazilian Journal of Functional Nutrition
NUTRIÇÃO
FUNCIONAL
ano 17. edição 70
www.vponline.com.br
ISSN 2176-4522
O efeito da carqueja (Baccharis trimera)
na síndrome metabólica: estudo de caso
Envelhecimento saudável, exercício físico,
nutrientes estimulantes e a biogênese mitocondrial
Dieta Cetogênica :
como colocar em prática?
RECEITA
Barra de cereal funcional
Coordenação e Autores
4
Revista Brasileira de Nutrição Funcional
Coordenação e Autores
Anna Cecília Queiroz de Medeiros
       

Experiência na área de Nutrição, com ênfase em Nutrição e metabolismo de nutrientes nos diversos estados

Fáma Aparecida Arantes Sardinha


EPM. Docente convidada do curso de pós-graduação em Nutrição Clínica Funcional da VP Centro de Nutrição
Funcional em parceria com a Universidade Cruzeiro do Sul.
Fernanda Serpa


Funcional da VP Centro de Nutrição Funcional em parceria com a Universidade Cruzeiro do Sul. Docente
convidada dos cursos de pós-graduação e extensão da VP Centro de Nutrição Funcional em parceria com


Gilber Hübscher


dos cursos de pós-graduação em Nutrição Clínica Funcional da VP Centro de Nutrição Funcional em parceria


Márcia Crisna Paiva

pós-graduanda em Fitoterapia Funcional da VP Centro de Nutrição Funcional em parceria com a Universidade


dos Campos - SP.
Rosangela Passos de Jesus

de Medicina da USP. Mestre em Nutrição pela Universidade Federal de São Paulo. Especialista em Nutrição
Clínica Funcional, coordenadora do Ambulatório de Nutrição e Hepatologia do Hospital Universitário Prof
Edgard Santos.
Sandra Matsudo

doutorado em Ciências pela Escola Paulista de Medicina - UNIFESP. Diretora Geral do Centro de Estudos do





Valéria Paschoal
     
   
   
Universidade Cruzeiro do Sul. Diretora da VP Centro de Nutrição Funcional. Autora dos Livros “Nutrição

 
The
Instute for Funconal Medicine Community Supported Agriculture -


5
www.vponline.com.br
Coordenação e Autores
Lista de Autores
Crisane de Oliveira Cravo
 
em Nutrição Clínica Funcional pela Universidade Cruzeiro do Sul em parceria com a VP Centro de Nutrição

graduação Universidade Cruzeiro do Sul em parceria com a VP Centro de Nutrição Funcional. Docente de

Débora Kelly Oliveira das Neves



consultório.
Gabriela Pimentel
Nutricionista graduada pela Universidade Federal de Santa Catarina. Pós-graduada em Nutrição nas doenças
crônico não transmissíveis pelo Albert Einstein. Pós-graduada em Nutrição Clínica Funcional pela Universidade
Cruzeiro do Sul. Pós-graduada em Fitoterapia Funcional pela Universidade Cruzeiro do Sul. Docente dos
cursos de pós-graduação em Fitoterapia Funcional Universidade Cruzeiro do Sul. Atua em atendimento
clínico nutricional em consultório.
Gustavo Barbosa dos Santos
   

Hugo Comparoo



   


Isabela Pereira Gouveia
Graduanda em Nutrição pelo Centro Universitário São Camilo. Estagiária em Nutrição no departamento

Luiz Lannes Loureiro
 



especiais.
Rodrigo Minoru Manda




      
colaborador do Centro de Metabolismo em Exercício e Nutrição (CeMENutri) da Faculdade de Medicina de

Wagner Alessandro dos Reis



Pós-graduando em Nutrição Clínica Funcional pela Universidade Cruzeiro do Sul. Docente convidado do curso

Personal Nutrion 
palestras em empresas, escolas e academias.
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Revista Brasileira de Nutrição Funcional
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7
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Nitrato: suplementação, fontes dietéticas e efeitos na performance
Receita: Tortinha de Legumes com Taioba
Interpretando a dosagem da vitamina B12
Série Agroecologia: Parte II - A importância das abelhas para a agroecologia
Astragalus membranaceus e os seus benefícios para a saúde: um estudo de caso
Os efeitos da vitamina D na hipertroa muscular
7
www.vponline.com.br
Luiz Lannes Loureiro e Gustavo Barbosa dos Santos
Nitrato: suplementação, fontes dietéticas e
efeitos na performance
Nitrate: supplementation, dietary sources and effects on performance
Resumo




3
- 3
-





Abstract
Nitric oxide (NO) plays an important role in regulating functional and physiological parameters related to sports performance. It has
been recently recognized to favor muscle ber type shifting, as well as having vasodilator and hypotensive properties and the potential
to improve both energetic eciency and muscular contraction. Its main production pathway depends on nitric oxide synthase, i.e.,
oxygen dependent enzymes that have their function reduced during hypoxia. In such conditions, NO can be produced from inorganic
nitrate (NO3
-) and nitrite provided by a healthy diet. Higher ingestions of (NO3
-), derived either from food or supplements, seem to
benet sports performance in various types of exercises. However, its ergogenic eects depend on the duration of exercise, modality
and the subject's physical conditioning, as well as on the dose of NO previously ingested. The benets of supplementing NO seem to be
greater in subjects with inferior physical conditioning than in those well trained. In addition, NO supplementation appears to be more
eective in improving performance when the subject is under a high intensity and short duration training rather than an endurance
training protocol.
Keywords: Nitrate, Beetroot Juice, High intensity, Performance, Endurance.
8
Revista Brasileira de Nutrição Funcional
Luiz Lannes Loureiro e Gustavo Barbosa dos Santos
N
Introdução

macronutrientes e micronutrientes com capacidade





arterial2
de O2, fosfocreatina e custo por ATP3, estímulo
 4
5, captação de glicose
6     
7

   

L-arginina em L-citrulina na reação catalisada
pelas enzimas da família das óxido nítrico
8

32
-), ocorria independente
    in vitro9  
10      




     
    
oxig
mais importância durante o exercício físico de

11
               

ê
     


--2+ 
NO3
-2
-
Fonte: Traduzido de Jones12
Figura 1. Vias de produção do NO.
Dieta
NO
NO
L-Arginina +O
NOS
NO
Vasodilatação
Angiogênese 
mitocondrial 
mitocondrial
Captação de
glicose
Manipulação
de Ca2+

à fadiga 
 Desempenho

9
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Nitrato: suplementação, fontes dietéticas e efeitos na performance

13
32
-

por ação da nitrato redutase (Figura 2) e, então,
ômago14

15,16
   
     
   
   

a ingestão em bolus17
proteínas e nutrientes, incluindo xantina oxidase,
  

18,19
   
 




Fonte:22
Figura 2. A circulação entero-salivar do nitrato em seres humanos.
Nitrato, e pouco nitrito,
oriundos da alimentação

reduzem nitrato em nitrito
No meio ácido presente
no estômago, ocorre

nitrito em NO
Nitrato e nitrito
remanescente
são absorvidos no

Nitrato é excretado
pelos rins
Nitrato e nitrito sanguíneos,
originados da alimentação e
produção sistêmica de NO

ciclo entero-salivar por meio

    
     20 e,

 20,21, reiniciando o ciclo

    
 20  


10
Revista Brasileira de Nutrição Funcional
Luiz Lannes Loureiro e Gustavo Barbosa dos Santos
Fontes alimentares e biodisponibilidade
    
23,24
23,25
    
   26, e as doses usuais dos


kg12,27,28
   

    


29,30
    
realizados com alimentos produzidos em solo

Apesar de o suco de beterraba ser a fonte de
nitrato inorgânico mais utilizada nos estudos
   

    
   
aumento do consumo de nitrato13
26    

    

31

conforme o teor de nitrato por 100 g de alimento



sendo 0,1 mmol para cada 6,4 mg29

  
 32
compararam a biodisponibilidade entre nitrato de
sódio, espinafre, alface e beterraba e concluíram



Fonte:13
Tabela 1

(mg) em 100 g de
alimento fresco
Alimentos
Muito baixo < 20 mg
50 mg
Moderado < 100 mg
Alto < 250 mg
Muito alto > 250 mg
Aspargo, cebola, feijão, cogumelos, ervilha, pimenta,
tomate, melancia e alho
     
chicória

Avelã, repolho chinês, endívia, funcho, alho-poró,
salsinha e couve-rábano
Aipo, agrião, cerefólio, alface, beterraba, espinafre e

Nitrato e exercício de endurance
 33   
suplementação de cristais de beterraba combinados

       

     
    



    
     
11
www.vponline.com.br
Nitrato: suplementação, fontes dietéticas e efeitos na performance
suplementação de beterraba foi realizada durante


  

cinco doses dadas a cada 15 minutos, começando
 
   

    34 utilizaram
a suplementação de suco de beterraba em
   
    
    




 

    
 não aconteça por


    
de endurance35

    
    
contra o relógio, tempo de exaustão e esforço
 

  
      


3


   

da utilização de O2, para mesma intensidade
de exercício e de fosfocreatina, demonstrando


    
    
 
  


    

    
 2max), tipo, dose
e duração da suplementação, influenciou nos


no teste de exaustão (e apenas nele), esta situação

a competição de endurance  
     


    
endurance
Variáveis de interferência no efeito da
suplementação
   

  
2
36    
2pico

dias de nitrato inorgânico (5,5 mmol), realizando
   
       

    
 Os grupos baixo e moderado
2 e do tempo de

23
  

   
   

   
37    

2max
    
12
Revista Brasileira de Nutrição Funcional
Luiz Lannes Loureiro e Gustavo Barbosa dos Santos
2max
  

2max
    
    

    
    
    
       
38
a suplementação de nitrato de sódio e de suco

crossover  
    

2pico com diferentes dosagens de nitrato (3,


controlada e não ingeriram alimentos ricos em


A suplementação de beterraba com 6 mmol foi



de beterraba reduziu a pressão arterial sistólica
     

    


     

    
39
tempo de conclusão do exercício de intensidade
  
      
   
40   

suplementação crônica de suco de beterraba (15




    
nitrato sobre a performance do exercício de
endurance são, em sua maioria, discretos e
    
   
demonstrando efeito 

intensidade41-46

Efeitos do nitrato no exercício de alta in-
tensidade
    
nitrato em exercícios de alta intensidade parece
ocorrer tanto pela diminuição do consumo de O2,

da respiração mitocondrial5
da contração muscular3 
48



redução do consumo de O2 


   48 sugeriram


2
 e
Pi, modulação do metabolismo
     
Outros estudos49,50   
   


  50    
   

   
140 mL de suco de beterraba (11,2 mmol) ou
      
   
 
49
de beterraba (8,4 mmol) por 9 dias pode aumentar
    
13
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Nitrato: suplementação, fontes dietéticas e efeitos na performance
   
    





  51  
    
    

em cicloergômetro (4 a 6 sprints de 30 segundos
    
    
   
    
     
    

  
o teste em cicloergômetro ocorreu dentro de

m, reduzindo a fração inspirada de O2 de 20,9

grupos com exercício reduziram a proporção de
      


   
52 realizaram protocolo de suplementação de 4
semanas com suco de beterraba (13 mmol) em 36



    
    

Todos os grupos realizaram teste de protocolo de
rampa em cicloergômetro e, após 10 minutos, teste

suplementação, os grupos exercitados realizaram

   
sprints
    
    sprints2
      





   
      
suplementado em comparação aos outros grupos, e



    


   3 pode ser



em modalidades intermitentes de alta intensidade

     
    53
realizaram estudo muito bem controlado, com

washout
proibição do uso de enxaguante bucal para não

13 atletas de diferentes esportes com testes
     
       
beterraba rico (11,2 mmol) e pobre em nitrato
   
    







de estudo crossover com suplementação de
     
   
  performance


  Wingate
    
   54
14
Revista Brasileira de Nutrição Funcional
Luiz Lannes Loureiro e Gustavo Barbosa dos Santos

    
    



 55   
suplementação de suco de beterraba (6,4 mmol)
sprint (5,

de alta intensidade (Yo-Yo test) em comparação

      
     



(Yo-yo test)    
   

    
   
se compararmos os resultados das Olimpíadas do


56
57 examinaram o efeito da
suplementação de suco de beterraba na recuperação
     
    sprints

 
    
sprints
ingeriu duas garrafas de 250 ml cada, sendo uma


   
 e limiar de dor


 58  

com 140 mL de suco de beterraba (12,5 mmol)
 

com nitrato aumentou a biodisponibilidade do

    
   
    
    
     
3 parece ser
   
ou de alta intensidade e curta duração, tais como



59

com suco de beterraba concentrado (400 mg - 6,4
mmol) ou placebo, durante seis dias, antes do teste

     
    

tendo a mesma percepção de esforço em relação
   

Conclusão

   
      
    
como condicionamento físico, tipo e duração do

   
     
exercícios de alta intensidade e curta duração

endurance. Ademais, doses
       


Referências
  Free Radic Biol
Med
15
www.vponline.com.br
Nitrato: suplementação, fontes dietéticas e efeitos na performance

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   Avaliação das concentrações de nitrato e nitrito em hortaliças produzidas em
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
in humans. Toxicol Le
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
Int J Sport Nutr Exerc Metab; 9: 1-24, 2017.

Performance. J Strength Cond Res; 30 (12): 3520-4, 2016.
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Abstract Purpose This study evaluated the effects of dietary nitrate (NO3-) supplementation on physiological functioning and exercise performance in trained runners/ triathletes conducting short and longer distance treadmill running time-trials (TT). Method Eight trained male runners or triathletes completed four exercise performance tests comprising a 10 minute warm up followed by either a 1500 m or 10,000 m treadmill TT. Exercise performance tests were preceded 3 hours before the exercise by supplementation with either 140 ml concentrated nitrate-rich (~ 12.5 mmol nitrate) (BRJ) or nitrate-deplete (~ 0.01 mmol nitrate) (PLA) beetroot juice. Results BRJ supplementation significantly elevated plasma [NO2-] (P < 0.05). Resting blood pressure and exercise V̇O2 were not significantly different between BRJ and PLA (P > 0.05). However, post-exercise blood [lactate] was significantly greater in BRJ following the 1500 m TT (6.6 ± 1.2 vs. 6.1 ± 1.5 mM; P < 0.05), but not significantly different between conditions in the 10,000 m TT (P > 0.05). Performance in the 1500 m TT was significantly faster in BRJ versus PLA (319.6 ± 36.2 vs. 325.7 ± 38.8 s; P < 0.05). Conversely, there was no significant difference in 10,000 m TT performance between conditions (2643.1 ± 324. 1 vs. 2649.9 ± 319.8 s, P > 0.05). Conclusion Acute BRJ supplementation significantly enhanced 1500 m but not 10,000 m TT performance. These findings suggest that BRJ might be ergogenic during shorter-distance TTs which allow for a high work rate, but not during longer-distance TTs, completed at a lower work rate.
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Background While it is well established that dietary nitrate reduces the metabolic cost of exercise, recent evidence suggests this effect is maintained 24 h following the final nitrate dose when plasma nitrite levels have returned to baseline. In addition, acute dietary nitrate was recently reported to enhance peak power production. Our purpose was to examine whether chronic dietary nitrate supplementation enhanced peak power 24 h following the final dose and if this impacted performance in a heavily power-dependent sport. Methods In a double-blind, randomized, crossover design, maximal aerobic capacity, body composition, strength, maximal power (30 s Wingate), endurance (2 km rowing time trial), and CrossFit performance (Grace protocol) were assessed before and after six days of supplementation with nitrate (NO) (8 mmol·potassium nitrate·d⁻¹) or a non-caloric placebo (PL). A 10-day washout period divided treatment conditions. Paired t-tests were utilized to assess changes over time and to compare changes between treatments. Results Peak Wingate power increased significantly over time with NO (889.17 ± 179.69 W to 948.08 ± 186.80 W; p = 0.01) but not PL (898.08 ± 183.24 W to 905.00 ± 157.23 W; p = 0.75). However, CrossFit performance was unchanged, and there were no changes in any other performance parameters. Conclusion Consuming dietary nitrate in the potassium nitrate salt form improved peak power during a Wingate test, but did not improve elements of strength or endurance in male CrossFit athletes.
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Purpose: To investigate the effects of NO3(-) supplementation on sprint running performance, and cognitive function and exercise performance during the sport-specific Yo-Yo Intermittent Recovery level 1 test (IR1). Methods: In a double-blind, randomised, crossover study, 36 male team-sport players received NO3(-)-rich (BR; 70 mL·day(-1); 6.4 mmol of NO3(-)), and NO3(-)-depleted (PL; 70 mL·day(-1); 0.04 mmol NO3(-)) beetroot juice for 5 days. On day 5 of supplementation, subjects completed a series of maximal 20-m sprints followed by the Yo-Yo IR1. Cognitive tasks were completed prior to, during and immediately following the Yo-Yo IR1. Results: BR improved sprint split times relative to PL at 20 m (1.2%; BR 3.98 ± 0.18 vs. PL 4.03 ± 0.19 s; P < 0.05), 10 m (1.6%; BR 2.53 ± 0.12 vs. PL 2.57 ± 0.19 s; P < 0.05) and 5 m (2.3%; BR 1.73 ± 0.09 vs. PL 1.77 ± 0.09 s; P < 0.05). The distance covered in the Yo-Yo IR1 test improved by 3.9% (BR 1422 ± 502 vs. PL 1369 ± 505 m; P < 0.05). The reaction time to the cognitive tasks was shorter in BR (615 ± 98 ms) than PL (645 ± 120 ms; P < 0.05) at rest but not during the Yo-Yo IR1. There was no difference in response accuracy. Conclusions: Dietary NO3(-) supplementation enhances maximal sprint and high-intensity intermittent running performance in competitive team sport players. Our findings suggest that NO3(-) supplementation has the potential to improve performance in single-sprint or multiple-sprint (team) sports.