Influence of caffeine on perception of effort, metabolism and exercise performance following a high-fat meal
- 1 August 2006
- journal article
- research article
- Published by Taylor & Francis Ltd in Journal of Sports Sciences
- Vol. 24 (8), 875-887
- https://doi.org/10.1080/02640410500249399
Abstract
This study examined the effects of caffeine, co-ingested with a high fat meal, on perceptual and metabolic responses during incremental (Experiment 1) and endurance (Experiment 2) exercise performance. Trained participants performed three constant-load cycling tests at approximately 73% of maximal oxygen uptake ([Vdot]O2max) for 30 min at 20°C (Experiment 1, n = 8) and to the limit of tolerance at 10°C (Experiment 2, n = 10). The 30 min constant-load exercise in Experiment 1 was followed by incremental exercise (15 W · min−1) to fatigue. Four hours before the first test, the participants consumed a 90% carbohydrate meal (control trial); in the remaining two tests, the participants consumed a 90% fat meal with (fat + caffeine trial) and without (fat-only trial) caffeine. Caffeine and placebo were randomly assigned and ingested 1 h before exercise. In both experiments, ratings of perceived leg exertion were significantly lower during the fat + caffeine than fat-only trial (Experiment 1: P < 0.001; Experiment 2: P < 0.01). Ratings of perceived breathlessness were significantly lower in Experiment 1 (P < 0.01) and heart rate higher in Experiment 2 (P < 0.001) on the fat + caffeine than fat-only trial. In the two experiments, oxygen uptake, ventilation, blood [glucose], [lactate] and plasma [glycerol] were significantly higher on the fat + caffeine than fat-only trial. In Experiment 2, plasma [free fatty acids], blood [pyruvate] and the [lactate]:[pyruvate] ratio were significantly higher on the fat + caffeine than fat-only trial. Time to exhaustion during incremental exercise (Experiment 1: control: 4.9, s = 1.8 min; fat-only: 5.0, s = 2.2 min; fat + caffeine: 5.0, s = 2.2 min; P > 0.05) and constant-load exercise (Experiment 2: control: 116 (88 – 145) min; fat-only: 122 (96 – 144) min; fat + caffeine: 127 (107 – 176) min; P > 0.05) was not different between the fat-only and fat + caffeine trials. In conclusion, while a number of metabolic responses were increased during exercise after caffeine ingestion, perception of effort was reduced and this may be attributed to the direct stimulatory effect of caffeine on the central nervous system. However, this caffeine-induced reduction in effort perception did not improve exercise performance.Keywords
This publication has 34 references indexed in Scilit:
- Effect of different protocols of caffeine intake on metabolism and endurance performanceJournal of Applied Physiology, 2002
- Influence of caffeine on metabolic and cardiovascular functions during sustained light intensity cycling and at rest.International Journal of Sport Nutrition, 1999
- Tissue‐specific effects ofin vivoadenosine receptor blockade on glucose uptake in Zucker ratsThe FASEB Journal, 1998
- Effect of Caffeine Ingestion on Perception of Effort and Subsequent Work ProductionInternational Journal of Sport Nutrition, 1996
- Caffeine Ingestion Prior to Incremental Cycling to Exhaustion in Recreational CyclistsInternational Journal of Sports Medicine, 1990
- Caffeine: a double-blind, placebo-controlled study of its thermogenic, metabolic, and cardiovascular effects in healthy volunteersThe American Journal of Clinical Nutrition, 1990
- A simple one-step enzymatic fluorometric method for the determination of glycerol in 20 μl of plasmaClinica Chimica Acta; International Journal of Clinical Chemistry, 1983
- Effects of Caffeine Ingestion on Utilization of Muscle Glycogen and Lipid During Leg Ergometer CyclingInternational Journal of Sports Medicine, 1980
- On-line computer analysis and breath-by-breath graphical display of exercise function tests.Journal of Applied Physiology, 1973
- Diet, Muscle Glycogen and Physical PerformanceActa Physiologica Scandinavica, 1967