PMID- 8891498
OWN - NLM
STAT- MEDLINE
DCOM- 19970218
LR  - 20190830
IS  - 0301-5548 (Print)
IS  - 0301-5548 (Linking)
VI  - 74
IP  - 1-2
DP  - 1996
TI  - Fuel kinetics during intense running and cycling when fed carbohydrate.
PG  - 36-43
AB  - On two occasions, six well-trained, male competitive triathletes performed, in 
      random order, two experimental trials consisting of either a timed ride to 
      exhaustion on a cycle ergometer or a run to exhaustion on a motor-driven 
      treadmill at 80% of their respective peak cycling and peak running oxygen (VO2 
      max) uptakes. At the start of exercise, subjects drank 250 ml of a 15 g.100 ml-1 
      w/v [U-14C]glucose solution and, thereafter, 150 ml of the same solution every 15 
      min. Despite identical metabolic rates [VO2 3.51 (0.06) vs 3.51 (0.10) 1.min-1; 
      values are mean (SEM) for the cycling and running trials, respectively], exercise 
      times to exhaustion were significantly longer during cycling than running [96 
      (14) vs 63 (11) min; P < 0.05]. The superior cycling than running endurance was 
      not associated with any differences in either the rate of blood glucose oxidation 
      [3.8 (0.1) vs 3.9 (0.4) mmol.min-1], or the rate of ingested glucose oxidation 
      [2.0 (0.1) vs 1.7 (0.2) mmol.min-1] at the last common time point (40 min) before 
      exhaustion, despite higher blood glucose concentrations at exhaustion during 
      running than cycling [7.0 (0.9) vs 5.8 (0.5) mmol.l-1; P < 0.05]. However, the 
      final rate of total carbohydrate (CHO) oxidation was significantly greater during 
      cycling than running [24.0 (0.8) vs 21.7 (1.4) mmol C6.min-1; P < 0.01]. At 
      exhaustion, the estimated contribution to energy production from muscle glycogen 
      had declined to similar extents in both cycling and running [68 (3) vs 65 (5)%]. 
      These differences between the rates of total CHO oxidation and blood glucose 
      oxidation suggest that the direct and/or indirect (via lactate) oxidation of 
      muscle glycogen was greater in cycling than running.
FAU - Derman, K D
AU  - Derman KD
AD  - Department of Physiology, University of Cape Town Medical School, Observatory, 
      South Africa.
FAU - Hawley, J A
AU  - Hawley JA
FAU - Noakes, T D
AU  - Noakes TD
FAU - Dennis, S C
AU  - Dennis SC
LA  - eng
PT  - Clinical Trial
PT  - Comparative Study
PT  - Journal Article
PT  - Randomized Controlled Trial
PT  - Research Support, Non-U.S. Gov't
PL  - Germany
TA  - Eur J Appl Physiol Occup Physiol
JT  - European journal of applied physiology and occupational physiology
JID - 0410266
RN  - 0 (Blood Glucose)
RN  - 0 (Dietary Carbohydrates)
RN  - 0 (Insulin)
RN  - 0 (Lactates)
SB  - IM
MH  - Adult
MH  - *Bicycling
MH  - Blood Glucose/metabolism
MH  - Dietary Carbohydrates/*pharmacology
MH  - Energy Metabolism/drug effects/*physiology
MH  - Exercise/*physiology
MH  - Humans
MH  - Insulin/blood
MH  - Kinetics
MH  - Lactates/blood
MH  - Lipid Metabolism
MH  - Male
MH  - Oxidation-Reduction
MH  - Oxygen Consumption/drug effects/physiology
MH  - Physical Endurance/drug effects/physiology
MH  - Pulmonary Gas Exchange
MH  - *Running
EDAT- 1996/01/01 00:00
MHDA- 1996/01/01 00:01
CRDT- 1996/01/01 00:00
PHST- 1996/01/01 00:00 [pubmed]
PHST- 1996/01/01 00:01 [medline]
PHST- 1996/01/01 00:00 [entrez]
AID - 10.1007/BF00376492 [doi]
PST - ppublish
SO  - Eur J Appl Physiol Occup Physiol. 1996;74(1-2):36-43. doi: 10.1007/BF00376492.