PMID- 2689427
OWN - NLM
STAT- MEDLINE
DCOM- 19900208
LR  - 20171213
IS  - 8750-7587 (Print)
IS  - 0161-7567 (Linking)
VI  - 67
IP  - 5
DP  - 1989 Nov
TI  - Effects of 4- and 8-h preexercise feedings on substrate use and performance.
PG  - 2066-71
AB  - Seven well-trained male cyclists were studied during 105 min of cycling (65% of 
      maximal oxygen uptake) and a 15-min "performance ride" to compare the effects of 
      4- and 8-h preexercise carbohydrate (CHO) feedings on substrate use and 
      performance. A high CHO meal was given 1) 4-h preexercise (M-4), 2) 8-h 
      preexercise (M-8), 3) 4-h preexercise with CHO feedings during exercise (M-4CHO), 
      and 4) 8-h preexercise with CHO feedings during exercise (M-8CHO). Blood samples 
      were obtained at 0, 15, 60, 105, and 120 min and analyzed for lactate, glucose, 
      insulin, and glycerol. Total work output during the performance ride was similar 
      for the M-4 (217,893 +/- 13,348 N/m) and M-8 trials (216,542 +/- 13,905) and was 
      somewhat higher for the M-4CHO (223,994 +/- 14,387) and M-8CHO (224,702 +/- 
      15,709) trials (P = 0.059, NS). Glucose was significantly elevated throughout 
      exercise, and insulin levels were significantly elevated at 15 and 60 min during 
      M-4CHO and M-8CHO compared with M-4 and M-8 trials. Glycerol levels were 
      significantly lower during the CHO feeding trials compared with placebo and were 
      not significantly different during exercise when the subject had fasted an 
      additional 4 h. The results of this study suggest that when preexercise meals are 
      ingested 4 or 8 h before submaximal cycling exercise, substrate use and 
      performance are similar.
FAU - Flynn, M G
AU  - Flynn MG
AD  - Department of Health Promotion and Human Performance, University of Toledo, Ohio 
      43606.
FAU - Michaud, T J
AU  - Michaud TJ
FAU - Rodriguez-Zayas, J
AU  - Rodriguez-Zayas J
FAU - Lambert, C P
AU  - Lambert CP
FAU - Boone, J B
AU  - Boone JB
FAU - Moleski, R W
AU  - Moleski RW
LA  - eng
PT  - Clinical Trial
PT  - Controlled Clinical Trial
PT  - Journal Article
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 (Insulin)
RN  - 0 (Lactates)
RN  - PDC6A3C0OX (Glycerol)
SB  - IM
MH  - Adult
MH  - Blood Glucose/metabolism
MH  - Dietary Carbohydrates/*pharmacology
MH  - Exercise Test
MH  - Glycerol/blood
MH  - Hemodynamics
MH  - Humans
MH  - Insulin/blood
MH  - Lactates/blood
MH  - Oxygen Consumption
MH  - Physical Exertion/*physiology
MH  - Time Factors
EDAT- 1989/11/01 00:00
MHDA- 1989/11/01 00:01
CRDT- 1989/11/01 00:00
PHST- 1989/11/01 00:00 [pubmed]
PHST- 1989/11/01 00:01 [medline]
PHST- 1989/11/01 00:00 [entrez]
AID - 10.1152/jappl.1989.67.5.2066 [doi]
PST - ppublish
SO  - J Appl Physiol (1985). 1989 Nov;67(5):2066-71. doi: 10.1152/jappl.1989.67.5.2066.