Caffeine, exercise physiology, and time-trial performance: no effect of ADORA2A or CYP1A2 genotypes.
Appl Physiol Nutr Metab
; 46(6): 541-551, 2021 Jun.
Article
em En
| MEDLINE
| ID: mdl-33170731
ABSTRACT
The aim of this study was to investigate the influence of ADORA2A and CYP1A2 genotypes on the physiological and ergogenic effects of caffeine. Sixty-six male cyclists were screened for ADORA2A and CYP1A2 genotypes; with 40 taking part subsequently in a randomised, double-blind, placebo-controlled study. Trial 1 was used to establish the oxygen uptake-power output relationship and maximal oxygen uptake. In trials 2 and 3, participants ingested 5 mg·kg-1 of caffeine or placebo 1 h before completing a submaximal incremental cycling test, followed by a time-trial (â¼30 min). Relative to placebo, caffeine led to a significant reduction in time to complete the time-trial (caffeine 29.7 ± 1.8 min; placebo 30.8 ± 2.3 min); but there was no effect of genotype. During submaximal exercise, caffeine reduced mean heart rate by 2.9 ± 3.7 beats·min-1, with effects dissipating as exercise intensity increased. Caffeine also significantly reduced perceived exertion by 0.5 ± 0.8, and increased blood lactate by 0.29 ± 0.42 mmol·L-1, respiratory exchange ratio by 0.013 ± 0.032, and minute ventilation by 3.1 ± 6.8 L·min-1. Nonetheless, there were no supplement × genotype interactions. In conclusion, caffeine influences physiological responses to submaximal exercise and improves time-trial performance irrespective of ADORA2A or CYP1A2 genotypes. Novelty Caffeine affects physiological responses at rest and during submaximal exercise independent of ADORA2A or CYP1A2 genotypes. Variability in the effect of caffeine on time-trial performance is not explained by ADORA2A or CYP1A2 genotypes.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Cafeína
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Exercício Físico
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Citocromo P-450 CYP1A2
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Receptor A2A de Adenosina
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Substâncias para Melhoria do Desempenho
Tipo de estudo:
Clinical_trials
Limite:
Adult
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Humans
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Male
Idioma:
En
Revista:
Appl Physiol Nutr Metab
Assunto da revista:
CIENCIAS DA NUTRICAO
/
FISIOLOGIA
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MEDICINA ESPORTIVA
/
METABOLISMO
Ano de publicação:
2021
Tipo de documento:
Article
País de afiliação:
Reino Unido