PMID- 9843546
OWN - NLM
STAT- MEDLINE
DCOM- 19990201
LR  - 20171213
IS  - 8750-7587 (Print)
IS  - 0161-7567 (Linking)
VI  - 85
IP  - 6
DP  - 1998 Dec
TI  - Carbohydrate intake during prolonged cycling minimizes effect of glycemic index 
      of preexercise meal.
PG  - 2220-6
AB  - We studied the effects of the glycemic index (GI) of preexercise meals on 
      metabolism and performance when carbohydrate (CHO) was ingested throughout 
      exercise. Six well-trained cyclists performed three counterbalanced trials of 2-h 
      cycling at approximately 70% of maximal oxygen uptake, followed by a performance 
      ride of 300 kJ. Meals consumed 2 h before exercise consisted of 2 g CHO/kg body 
      mass of either high-GI potato (HGI trial) or low-GI pasta (LGI trial), or of a 
      low-energy jelly (Con trial). Immediately before and throughout exercise, 
      subjects ingested a 10 g/100 ml [U-14C]glucose solution for a total of 24 ml/kg 
      body mass. Despite differences in preexercise glucose, insulin, and free fatty 
      acids concentrations among trials, both total CHO oxidation for HGI, LGI, and Con 
      trials, respectively, during steady-state exercise [403 +/- 16, 376 +/- 29, and 
      373 +/- 24 (SE) g/2 h] and oxidation of the ingested CHO (65 +/- 6, 57 +/- 6, and 
      63 +/- 5 g/2 h) were similar. There was no difference in time to complete the 
      subsequent performance ride (946 +/- 23, 954 +/- 35, and 970 +/- 26 s for HGI, 
      LGI, and Con trials, respectively). When CHO is ingested during exercise in 
      amounts presently recommended by sports nutrition guidelines, preexercise CHO 
      intake has little effect on metabolism or on subsequent performance during 
      prolonged cycling (approximately 2.5 h).
FAU - Burke, L M
AU  - Burke LM
AD  - Department of Sports Nutrition, Australian Institute of Sport, Bruce, Australian 
      Capital Territory 2617, Australia.
FAU - Claassen, A
AU  - Claassen A
FAU - Hawley, J A
AU  - Hawley JA
FAU - Noakes, T D
AU  - Noakes TD
LA  - eng
PT  - Clinical Trial
PT  - Journal Article
PT  - Randomized Controlled Trial
PT  - Research Support, Non-U.S. Gov't
PL  - United States
TA  - J Appl Physiol (1985)
JT  - Journal of applied physiology (Bethesda, Md. : 1985)
JID - 8502536
RN  - 0 (Blood Glucose)
RN  - 0 (Dietary Carbohydrates)
RN  - 0 (Fatty Acids, Nonesterified)
RN  - 0 (Insulin)
SB  - IM
MH  - Adult
MH  - Bicycling/physiology
MH  - Blood Glucose/*metabolism
MH  - Dietary Carbohydrates/*administration & dosage
MH  - Exercise/*physiology
MH  - Exercise Test
MH  - Fatty Acids, Nonesterified/blood
MH  - Humans
MH  - Insulin/blood
MH  - Male
MH  - Nutritional Physiological Phenomena
MH  - Physical Endurance/physiology
MH  - Time Factors
EDAT- 1998/12/08 00:00
MHDA- 1998/12/08 00:01
CRDT- 1998/12/08 00:00
PHST- 1998/12/08 00:00 [pubmed]
PHST- 1998/12/08 00:01 [medline]
PHST- 1998/12/08 00:00 [entrez]
AID - 10.1152/jappl.1998.85.6.2220 [doi]
PST - ppublish
SO  - J Appl Physiol (1985). 1998 Dec;85(6):2220-6. doi: 10.1152/jappl.1998.85.6.2220.