Red Spinach Extract Increases Ventilatory Threshold during Graded Exercise Testing.
Sports (Basel)
; 5(4)2017 Oct 16.
Article
em En
| MEDLINE
| ID: mdl-29910440
ABSTRACT
Background:
We examined the acute effect of a red spinach extract (RSE) (1000 mg dose; ~90 mg nitrate (NO 3 - )) on performance markers during graded exercise testing (GXT).Methods:
For this randomized, double-blind, placebo (PBO)-controlled, crossover study, 15 recreationally-active participants (aged 23.1 ± 3.3 years; BMI 27.2 ± 3.7 kg/m²) reported >2 h post-prandial and performed GXT 65â»75 min post-RSE or PBO ingestion. Blood samples were collected at baseline (BL), pre-GXT (65â»75 min post-ingestion; PRE), and immediately post-GXT (POST). GXT commenced with continuous analysis of expired gases.Results:
Plasma concentrations of NO 3 - increased PRE (+447 ± 294%; p < 0.001) and POST (+378 ± 179%; p < 0.001) GXT with RSE, but not with PBO (+3 ± 26%, -8 ± 24%, respectively; p > 0.05). No effect on circulating nitrite (NO 2 - ) was observed with RSE (+3.3 ± 7.5%, +7.7 ± 11.8% PRE and POST, respectively; p > 0.05) or PBO (-0.5 ± 7.9%, -0.2 ± 8.1% PRE and POST, respectively; p > 0.05). When compared to PBO, there was a moderate effect of RSE on plasma NO 2 - at PRE (g = 0.50 [-0.26, 1.24] and POST g = 0.71 [-0.05, 1.48]). During GXT, VO2 at the ventilatory threshold was significantly higher with RSE compared to PBO (+6.1 ± 7.3%; p < 0.05), though time-to-exhaustion (-4.0 ± 7.7%; p > 0.05) and maximal aerobic power (i.e., VO2 peak; -0.8 ± 5.6%; p > 0.05) were non-significantly lower with RSE.Conclusions:
RSE as a nutritional supplement may elicit an ergogenic response by delaying the ventilatory threshold.
Texto completo:
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Coleções:
01-internacional
Base de dados:
MEDLINE
Tipo de estudo:
Clinical_trials
Idioma:
En
Revista:
Sports (Basel)
Ano de publicação:
2017
Tipo de documento:
Article
País de afiliação:
Estados Unidos