PMID- 19159946
OWN - NLM
STAT- MEDLINE
DCOM- 20090723
LR  - 20211020
IS  - 1439-6327 (Electronic)
IS  - 1439-6319 (Linking)
VI  - 106
IP  - 1
DP  - 2009 May
TI  - Effect of a 20-day ski trek on fuel selection during prolonged exercise at low 
      workload with ingestion of 13C-glucose.
PG  - 41-9
LID - 10.1007/s00421-009-0987-8 [doi]
AB  - Fuel selection was measured in five subjects (36.0 +/- 10.5 years old; 87.3 +/- 
      12.5 kg; mean +/- SD) during a 120-min tethered walking with ski poles (1.12 l 
      O(2) min(-1)) with ingestion of (13)C-glucose (1.5 g kg(-1)), before and after a 
      20-day 415-km ski trek [physical activity level (PAL) approximately 3], using 
      respiratory calorimetry, urea excretion, and (13)C/(12)C in expired CO(2) and in 
      plasma glucose. Before the ski trek, protein oxidation contributed 9.7 +/- 1.6% 
      to the energy yield (%En) while fat and carbohydrate (CHO) oxidation provided 
      73.5 +/- 5.5 and 16.7 +/- 6.5%En. Plasma glucose was the main source of CHO (52.9 
      +/- 9.5%En) with similar contributions from exogenous glucose (27.2 +/- 3.1%En), 
      glucose from the liver (25.6 +/- 8.3%En) and muscle glycogen (20.9 +/- 4.0%En). 
      Endogenous CHO contributed 46.6 +/- 3.9%En. Following the ski trek %En from 
      protein, fat, CHO, exogenous glucose and endogenous CHO were not significantly 
      modified (10.1 +/- 1.3, 15.8 +/- 6.7, 74.1 +/- 6.5, 28.7 +/- 3.0 and 45.5 +/- 
      7.5%En, respectively) but the %En from plasma glucose and glucose from the liver 
      (41.1 +/- 3.6 and 12.4 +/- 4.0%En) were reduced, while that from muscle glycogen 
      increased (33.0 +/- 4.5%En). These results show that in subjects in the fed state 
      with glucose ingestion during exercise, CHO is the main substrate oxidized, with 
      major contributions from both exogenous and endogenous CHO. Following a ~3-week 
      period of prolonged low intensity exercise, the %En from protein, fat, CHO, 
      exogenous glucose and endogenous CHO were not modified. However, the %En from 
      glucose released from the liver was reduced (possibly due to an increased insulin 
      sensitivity of the liver) while that from muscle glycogen was increased.
FAU - Peronnet, F
AU  - Peronnet F
AD  - Departement de kinesiologie, Universite de Montreal, Centre Ville, Montreal, QC, 
      Canada. francois.peronnet@umontreal.ca
FAU - Abdelaoui, M
AU  - Abdelaoui M
FAU - Lavoie, C
AU  - Lavoie C
FAU - Marrao, C
AU  - Marrao C
FAU - Kerr, S
AU  - Kerr S
FAU - Massicotte, D
AU  - Massicotte D
FAU - Giesbrecht, G
AU  - Giesbrecht G
LA  - eng
PT  - Clinical Trial
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
DEP - 20090122
PL  - Germany
TA  - Eur J Appl Physiol
JT  - European journal of applied physiology
JID - 100954790
RN  - 0 (Blood Glucose)
RN  - 0 (Carbon Isotopes)
RN  - 142M471B3J (Carbon Dioxide)
RN  - IY9XDZ35W2 (Glucose)
SB  - IM
MH  - Adult
MH  - Blood Glucose/metabolism
MH  - Carbon Dioxide/metabolism
MH  - Carbon Isotopes/administration & dosage/metabolism/pharmacology
MH  - Eating/physiology
MH  - Energy Metabolism/drug effects/physiology
MH  - Exercise/*physiology
MH  - Food Preferences/drug effects/*physiology
MH  - Glucose/administration & dosage/*metabolism/pharmacology
MH  - Humans
MH  - Male
MH  - Oxidation-Reduction
MH  - Physical Endurance/drug effects/physiology
MH  - Skiing/*physiology
MH  - Time Factors
MH  - *Workload
EDAT- 2009/01/23 09:00
MHDA- 2009/07/25 09:00
CRDT- 2009/01/23 09:00
PHST- 2009/01/06 00:00 [accepted]
PHST- 2009/01/23 09:00 [entrez]
PHST- 2009/01/23 09:00 [pubmed]
PHST- 2009/07/25 09:00 [medline]
AID - 10.1007/s00421-009-0987-8 [doi]
PST - ppublish
SO  - Eur J Appl Physiol. 2009 May;106(1):41-9. doi: 10.1007/s00421-009-0987-8. Epub 
      2009 Jan 22.