RESUMEN
The purpose of this study was to investigate the effects of acute nitrate (NO3-)-rich beetroot juice ingestion on explosive and high-intensity exercise performance, oral microbiota composition, and cognitive flexibility (i.e., function), before and after maximal intermittent running exercise. Fifteen women team-sport athletes were assigned in a randomized, double-blind, crossover design to consume concentrated NO3--depleted beetroot juice (PL; 0.1 mmol NO3-) and NO3--rich beetroot juice (BR; 12.0 mmol NO3-) 2.5 h prior to performing a battery of exercise performance tasks and cognitive testing before and after the Yo-Yo intermittent recovery level 1 (YYIR1) running test. Resting plasma [NO3-] and plasma nitrite ([NO2-]) were elevated following BR (P < 0.001). BR did not impact global composition or relative abundance of taxa in the oral microbiome (P > 0.05) or cognitive flexibility before or after exercise (P > 0.05). There was no significant difference in performance during 20-m (PRE, PL: 4.38 ± 0.27 vs. BR: 4.38 ± 0.32 s; POST, PL: 4.45 ± 0.29 vs. BR: 4.43 ± 0.35 s) and 10-m sprints (PRE, PL 2.78 ± 0.15 vs. BR 2.79 ± 0.18 s; POST, PL: 2.82 ± 0.16 vs. BR: 2.81 ± 0.19 s), isokinetic handgrip dynamometry, medicine ball throw, horizontal countermovement jump, or YYIR1 (PL: 355 ± 163 m vs. BR: 368 ± 184 m) between BR and PL (P > 0.05). These findings indicate that acute dietary NO3- may not influence the oral microbiome, explosive and high-intensity exercise performance, or cognitive function in women team-sport athletes.
RESUMEN
This study (a) examined the associations among different performance metrics derived from different strategies (i.e., maximum and average scores) and trials from product-oriented measures of motor skills, and (b) explored how different performance metrics from product-oriented assessments of motor skills change in young children with typical development. Children (N = 279; 156 girls; Mage = 4.44 years) completed a battery of product-oriented assessments for throwing (in meters per second, five trials); kicking (in meters per second, five trials); jumping (in centimeters, five trials); running (in meters per second, two trials); and hopping (in meters per second, four trials-two preferred foot, two nonpreferred foot). A total of 36 performance metrics were derived-throw (n = 7), kick (n = 7), jump (n = 7), run (n = 4), and hop (n = 11). Intraclass correlations examined reliability among performance metrics for each skill; linear mixed models examined whether variations changed across early childhood. There was excellent reliability among all performance metrics for each skill (all ICC> .90). Linear mixed models revealed that children's motor performance improved for two metrics of the throw, five variations of the jump, and three metrics of the hop (all p <.05). Researchers should be aware that some performance metrics from product-oriented assessments (e.g., maximum and average of three or five trials) are highly related and change, whereas others do not.