title: Carbohydrate-electrolyte drink ingestion and skill performance during and after 2 hr of indoor tennis match play.
abstract: Twenty-two tennis players were individually studied on 2 occasions. They performed a prematch skill test, a 2-hr tennis match against an equally ranked opponent, and a postmatch skill test. A carbohydrate-electrolyte (CHO-E; Lucozade Sport) or flavor-matched placebo-electrolyte (PL) beverage was administered in a double-blind fashion. During the trials, heart-rate and movement intensity were monitored, and the match was recorded for performance analysis. There were no differences in skill-test scores pre- to postmatch or between trials (154±38 pre- and 160±35 postmatch on PL, 155±36 pre- and 165±33 postmatch on CHO-E). CHO-E ingestion elevated blood glucose concentration throughout the match, and participants reported feeling more energetic (general activation) and more tense (high activation) 1 hr into the match than at baseline (p<.05). Participants in the CHO-E trial spent more time in moderate-intensity activity and less time in low-intensity activity than on PL. Performance analysis revealed that CHO-E ingestion increased overall serve success (M±SD, 68%±7% for CHO-E vs. 66%±7% for PL; p<.05) and success of first serves (65%±9% for CHO-E, 61%±7% for PL; p<.01) and serves to the advantage side (70%±9% for CHO-E, 66%±7% for PL; p<.05). Return success was greater during the second set of the match (p<.05) in the CHO-E trial. Differences in serve and return success were not associated with blood glucose response to CHO or player ability.
authors.affiliation: Health and Exercise Sciences Research Group, School of Sport, University of Stirling, Stirling, Scotland.
authors.forename: Kirsty A
authors.initials: KA
authors.lastname: McRae
authors.forename: Stuart D R
authors.initials: SD
authors.lastname: Galloway
mesh_terms: D000293:Adolescent; D000328:Adult; D054874:Athletic Performance / Q000502:physiology*; D001786:Blood Glucose / Q000032:analysis; D018592:Cross-Over Studies; D004040:Dietary Carbohydrates / Q000008:administration & dosage*; D019587:Dietary Supplements; D004311:Double-Blind Method; D004573:Electrolytes / Q000008:administration & dosage*; D005221:Fatigue / Q000097:blood / Q000517:prevention & control; D005260:Female; D006339:Heart Rate; D006801:Humans; D008297:Male; D009048:Motor Skills; D058573:Performance-Enhancing Substances / Q000008:administration & dosage*; D010807:Physical Endurance / Q000502:physiology*; D010809:Physical Fitness / Q000502:physiology*; D013715:Tennis; D055815:Young Adult
chemical_list: D001786:Blood Glucose; D004040:Dietary Carbohydrates; D004573:Electrolytes; D058573:Performance-Enhancing Substances