RESUMO
Background: The benefits of caffeine to physical performance have been extensively demonstrated, however, it has recently been speculated that there is an effect of the administration route on its effectiveness. Purpose: The current study investigated the effect of caffeine mouth rinse in isolation or combined with ingestion on performance in a 30-minute constant-load exercise followed by a 10-km cycling time trial. Methods: Ten physically active men performed a 30-minute constant-load exercise at 50% of the graded test Wmax, followed by a 10-km cycling time trial. Before and at the middle points of the constant-load exercise and 10-km cycling time trial, the following conditions were administered: PLA (cellulose ingestion plus mouth rinsing with magnesium sulfate), ING (5 mg.kg-1 of caffeine ingestion plus mouth rinsing with magnesium sulfate), MR (cellulose ingestion plus mouth rinsing with 1.2% caffeine), and COMB (5 mg.kg-1 of caffeine ingestion plus mouth rinsing with 1.2% caffeine). Results: During the 30-minute constant-load exercise, COMB presented a lower rating of perceived exertion (RPE) than MR (p = .04). For the 10-km time trial, the COMB was faster than MR (MR = 1363 ± 345 vs. COMB = 1291 ± 308s, Δ% = 5.57, p = .05). Mean power output was higher in COMB than PLA, ING, and MR (234 ± 15 vs. 169 ± 29, 148 ± 11, and 145 ± 12 W, respectively). There were no differences between conditions for heart rate and RPE during the 10-km time trial. Conclusion: In summary, caffeine mouth rinsing potentiated the effects of caffeine ingestion during the 10-km time trial compared to caffeine mouth rinsing alone.
RESUMO
Objetivos: Analisar a interação do consumo máximo de oxigênio com diferentes indicadores de risco cardiovascular entre adultos jovens do sexo masculino e sem histórico prévio de doenças. Métodos: Estudo transversal realizado com universitários. A amostra foi composta por 32 adultos jovens do sexo masculino e sem histórico prévio de doenças. Foram adotados como indicadores de risco: peso corporal, circunferência de cintura, percentual de gordura, glicemia em jejum, pressão arterial sistólica e diastólica. O consumo máximo de oxigênio foi avaliado de maneira direta em teste de esteira. A análise de variância e teste qui-quadrado analisaram os dados. Resultados: Menor consumo máximo de oxigênio associou-se com maior excesso de peso (p= 0,005), mas não com hipertensão (p= 0,059). Além disso, o mesmo associou-se com a menor ocorrência de riscos cardiovasculares. Conclusão: O consumo máximo de oxigênio é um indicador de risco mesmo entre adultos jovens sem diagnóstico prévio de doenças.
Objectives: To analyze the relationship between maximum oxygen uptake and cardiovascular risk factors among young male adults with no previously detected disease. Methods: Cross-sectional study with undergraduate subjects. The sample was composed by 32 young male adults without previously detected disease. Body weight, waist circumference, percentage body fat, fasting glucose, systolic and diastolic blood pressure were utilized as cardiovascular risk factors. Maximum oxygen uptake was assessed through treadmill test. Analysis of variance and chi-square test analyzed the data. Results: Lower maximum oxygen uptake was associated with higher overweight (p= 0,005), but not with arterial hypertension (p= 0,059). Moreover, the maximum oxygen uptake was also associated with lower occurrence of cardiovascular risk. Conclusion: The maximum oxygen uptake is an indicator of higher risk even among young adults without previously detected disease.
