Effects of carbohydrate and caffeine ingestion on performance during a rugby union simulation protocol.
In this study, we investigated the effect of ingesting carbohydrate alone or with caffeine on performance of a rugby union-specific shuttle running protocol. On three occasions, at least one week apart in a counterbalanced trial order, eight male rugby union forwards ingested either placebo or carbohydrate (1.2 g x kg(-1) body mass x h(-1)) before and during a rugby union-specific protocol, with pre-exercise caffeine ingestion (4 mg x kg(-1)) before one of the carbohydrate trials (carbohydrate + caffeine). The intermittent exercise protocol included walking, jogging, and cruising at pre-determined intensities, simulated contact events, a sustained high-intensity test of speed and agility (Performance Test), and a 15-m sprint. Ratings of perceived exertion (RPE) were recorded every 5 min and a motor skills test was performed after each 21-min block. Performance Test times were not significantly different between trials but the likelihood of 2% improvements for carbohydrate + caffeine over placebo and carbohydrate were 98% and 44%, respectively. For carbohydrate + caffeine, 15-m sprints were faster than for placebo (P=0.05) and the motor skills test was performed faster in the carbohydrate + caffeine trial than the carbohydrate and placebo trials (P < 0.05), while RPE was lower in the carbohydrate + caffeine trial than the carbohydrate and placebo trials (P < 0.05). The results indicate a likely benefit to rugby performance following co-ingestion of carbohydrate and caffeine.
Roberts
Simon P
SP
Sport and Exercise Science Research Group, School for Health, University of Bath, Bath, UK. spsspr@bath.ac.uk
Stokes
Keith A
KA
Trewartha
Grant
G
Doyle
Jenny
J
Hogben
Patrick
P
Thompson
Dylan
D
D000328:Adult; D054874:Athletic Performance / Q000502:physiology*; D002110:Caffeine / Q000494:pharmacology*; D040503:Coffea / Q000737:chemistry; D004040:Dietary Carbohydrates / Q000494:pharmacology*; D005538:Football / Q000502:physiology*; D006801:Humans; D008297:Male; D009048:Motor Skills / Q000187:drug effects*; D005082:Physical Exertion / Q000187:drug effects*; D010936:Plant Extracts / Q000494:pharmacology; D012420:Running / Q000502:physiology; D013997:Time Factors; D016138:Walking / Q000502:physiology; D055815:Young Adult
D004040:Dietary Carbohydrates; D010936:Plant Extracts; D002110:Caffeine