Coffee Ingestion Enhances 1-Mile Running Race Performance

Purpose: Caffeine, often in the form of coffee, is frequently supplemented by athletes in an attempt to facilitate improved performance during exercise. The aim of the present study was to investigate the effectiveness of coffee ingestion as an ergogenic aid prior to a one-mile (1609 m) race. Methods: In a double-blind, randomised, crossover, placebo-controlled design 13 trained male runners completed a one-mile race 60 minutes following the ingestion of 0.09 g·kg-1 coffee (COF), 0.09 g·kg-1 decaffeinated coffee (DEC), or a placebo (PLA). All trials were dissolved in 300 ml of hot water.Results:The race completion time was 1.3% faster following the ingestion of COF (04:35:37 ± 00:10:51 mm·ss) compared with DEC (04:39:14 ± 00:11:21 mm·ss; P=0.018; 95%CI: -0.11, -0.01; d=0.32) and 1.9% faster compared with PLA (04:41:00 ± 00:09:57 mm:ss; P=0.006; 95%CI: -0.15, -0.03; d=0.51). A large trial and time interaction for salivary caffeine concentration was observed (P<0.001; η2P=0.69) with a very large increase (6.40 ± 1.57 μg·ml-1, 95%CI: 5.5, 7.3; d=3.86) following the ingestion of COF. However, only a trivial difference between DEC and PLA was observed (P=0.602; 95%CI: -0.09, 0.03; d=0.17). Furthermore, only trivial differences for blood glucose (P=0.839; η2P=0.02) and lactate (P=0.096; η2P=0.18), and maximal heart rate (P=0.286; η2P=0.13) were observed between trials.Conclusions:The results of the present study show that 60 minutes after ingesting 0.09 g·kg-1 of caffeinated coffee one-mile race performance was enhanced by 1.9% and 1.3% compared with placebo and decaffeinated coffee respectively, in trained male runners

Can Doping be a Good Thing? Using Psychoactive Drugs to Facilitate Physical Activity Behaviour

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Efeitos do consumo agudo de cafeína sobre parâmetros metabólicos e de desempenho em indivíduos do sexo masculino Effects of caffeine acute consumption on the metabolic and performance parameters in male individuals

O objetivo deste estudo foi avaliar o efeito do consumo agudo de cafeína sobre a oxidação de lipídeos e desempenho durante o exercício aeróbico. Foram avaliados 15 indivíduos do sexo masculino, com idade média de 22,3 ± 2,7 anos, que realizaram teste de cargas progressivas em esteira rolante para determinação do consumo máximo de oxigênio (VO2máx) e limiares ventilatórios (LV). Cada voluntário realizou três testes submáximos na intensidade de 10% abaixo do segundo LV, sendo orientados a permanecer em exercício até a exaustão. Trinta minutos antes de cada teste submáximo, foram ingeridos 250ml de uma das bebidas compostas por: café com adoçante (CAD), café com açúcar (CA) e café descafeinado com adoçante (CD). Durante o exercício, os indivíduos foram monitorados pelo ergoespirômetro e frequencímetro. A oxidação de lipídeos foi predita pelo quociente respiratório (QR) durante o teste, e o desempenho foi verificado pelo tempo de exercício. Para comparar os resultados de QR e tempo de exercício entre os grupos, foi utilizado Anova fatorial, e considerou-se significância estatística um valor de p < 0,05. A média de VO2máx foi de 50,18 ± 9,9ml/kg/min. Com a ingestão de CAD, a média do QR foi de 0,98 ± 0,18 e o tempo médio em exercício foi de 24,1 ± 17,04 minutos. Com a ingestão de CA, a média do QR foi de 0,96 ± 0,2 e o tempo médio em exercício foi de 24,4 ± 17,8min. No teste com ingestão de CD, a média do QR foi de 1,01 ± 0,24 e a média do tempo em exercício foi de 20,6 ± 9,7min. Não houve diferença significativa entre os testes nos valores do QR e nem tempo de exercício (p = 0,697 e p = 0,598, respectivamente). A cafeína não aumentou a oxidação de lipídeos nem o desempenho de indivíduos jovens do sexo masculino.<br>The purpose of this study was to evaluate the effect of acute caffeine consumption on lipid oxidation and performance during aerobic exercise. Fifteen healthy male individuals, 22.3 ± 2.7 years old, performed a progressive test on treadmill for determination of maximal oxygen uptake (VO2max) and ventilatory thresholds. Each volunteer performed three submaximal tests at the intensity of 10% below the second ventilatory threshold, being guided to remain on exercise until exhaustion. Thirty minutes before each submaximal test, the subjects ingested 250ml of one of following drinks: coffee with sweetener (CSW), coffee with sugar (CS) or decaffeinated coffee with sweetener (CD). During the exercise, the individuals's heart rate was monitored and respiratory gases analyses were done. The lipid oxidation was predicted by the respiratory quotient (RQ) during the test and performance was verified by exercise duration. In order to compare the RQ results and time of exercise among the three groups, factorial Anova was used, and a value of p < 0.05 was considered as statistically significant. The individuals had VO2max of 50.18 ± 9.9 ml/kg/min. CAD ingestion caused RQ average of 0.98 ± 0.18, and the average exercise duration was of 24.1 ± 17.04 min; CA ingestion caused RQ average of 0.96 ± 0.2 and the average exercise duration was 24.4 ± 17.8 min. Finally, CD ingestion caused the RQ average of 1.01 ± 0.24, and the average exercise duration was of 20.6 ± 9.7 min. There were no significant differences in the RQ values or exercise duration among the three interventions (p = 0.697 and p = 0.598, respectively). Caffeine did not increase lipid oxidation or performance of young male individuals