PMID- 9509824
OWN - NLM
STAT- MEDLINE
DCOM- 19980407
LR  - 20170126
IS  - 0022-4707 (Print)
IS  - 0022-4707 (Linking)
VI  - 37
IP  - 4
DP  - 1997 Dec
TI  - Metabolic and ergogenic effects of carbohydrate and caffeine beverages in tennis.
PG  - 258-66
AB  - OBJECTIVE: Metabolic and ergogenic effects of carbohydrate and caffeine 
      concentrations, common in commercial available beverages, were investigated in 16 
      tournament players (8 males and 8 females) during a 4 hrs interrupted tennis 
      match (30 min rest after 150 min). METHODS: On three double-blind occasions 
      players ingested a placebo (PLA), carbohydrate (CHO) or caffeine drink (CAF) at 
      court changeover and during the resting period. In men (women) total intake 
      consisted of 2.8 l (2.0 l) fluid, supplemented with 243 g (182 g) carbohydrates 
      (CHO) or with 364 mg (260 mg) caffeine (CAF), respectively. Postexercise all 
      players performed a ball-machine test (BMT) and a tennis-sprint test (TST). 
      RESULTS: During match play blood glucose (GLU) was higher in CHO and did not 
      differ between CAF and PLA. Immediately after the resting period GLU temporary 
      declined in CHO and PLA, while no significant changes occurred in CAF. Increases 
      of serum FFA and glycerol as well as the decrease of insulin were similar during 
      the PLA and CAF trials and less pronounced in CHO. Postexercise urine 
      concentrations of epinephrine and caffeine were significantly higher in CAF. 
      Perception ratings and hitting accuracy (BMT) were not affected by treatment. CHO 
      resulted in higher blood lactate levels during match play and a better 
      post-exercise sprint performance (TST). Under CAF women won significantly more 
      games than during both other treatments. CONCLUSIONS: CHO enhances 
      tennis-specific running-speed but has no ergogenic effect on tennis performance 
      under the conditions of our study. CAF improves glucose homeostasis at the 
      beginning of work load after rest and may increase tennis success in women.
FAU - Ferrauti, A
AU  - Ferrauti A
AD  - Institute of Sports Games, German Sport University, Cologne, Germany.
FAU - Weber, K
AU  - Weber K
FAU - Struder, H K
AU  - Struder HK
LA  - eng
PT  - Clinical Trial
PT  - Controlled Clinical Trial
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - Italy
TA  - J Sports Med Phys Fitness
JT  - The Journal of sports medicine and physical fitness
JID - 0376337
RN  - 0 (Adrenergic Agonists)
RN  - 0 (Blood Glucose)
RN  - 0 (Dietary Carbohydrates)
RN  - 0 (Fatty Acids, Nonesterified)
RN  - 0 (Insulin)
RN  - 0 (Lactates)
RN  - 0 (Placebos)
RN  - 3G6A5W338E (Caffeine)
RN  - IY9XDZ35W2 (Glucose)
RN  - PDC6A3C0OX (Glycerol)
RN  - YKH834O4BH (Epinephrine)
SB  - IM
MH  - Adrenergic Agonists/urine
MH  - Adult
MH  - *Beverages
MH  - Blood Glucose/analysis
MH  - Caffeine/administration & dosage/*pharmacology/urine
MH  - Dietary Carbohydrates/administration & dosage/*pharmacology
MH  - Double-Blind Method
MH  - Energy Metabolism/*drug effects
MH  - Epinephrine/urine
MH  - Fatty Acids, Nonesterified/blood
MH  - Female
MH  - Glucose/metabolism
MH  - Glycerol/blood
MH  - Homeostasis/drug effects
MH  - Humans
MH  - Insulin/blood
MH  - Lactates/blood
MH  - Male
MH  - Motor Skills/drug effects
MH  - Perception/drug effects
MH  - Placebos
MH  - Psychomotor Performance/*drug effects
MH  - Rest/physiology
MH  - Running/physiology
MH  - Sex Factors
MH  - Tennis/*physiology
MH  - Work
EDAT- 1998/03/24 00:00
MHDA- 1998/03/24 00:01
CRDT- 1998/03/24 00:00
PHST- 1998/03/24 00:00 [pubmed]
PHST- 1998/03/24 00:01 [medline]
PHST- 1998/03/24 00:00 [entrez]
PST - ppublish
SO  - J Sports Med Phys Fitness. 1997 Dec;37(4):258-66.