PMID- 30840136
OWN - NLM
STAT- MEDLINE
DCOM- 20190731
LR  - 20200225
IS  - 1439-6327 (Electronic)
IS  - 1439-6319 (Print)
IS  - 1439-6319 (Linking)
VI  - 119
IP  - 5
DP  - 2019 May
TI  - Liver and muscle glycogen oxidation and performance with dose variation of 
      glucose-fructose ingestion during prolonged (3 h) exercise.
PG  - 1157-1169
LID - 10.1007/s00421-019-04106-9 [doi]
AB  - PURPOSE: This study investigated the effect of small manipulations in 
      carbohydrate (CHO) dose on exogenous and endogenous (liver and muscle) fuel 
      selection during exercise. METHOD: Eleven trained males cycled in a double-blind 
      randomised order on 4 occasions at 60% [Formula: see text] for 3 h, followed by a 
      30-min time-trial whilst ingesting either 80 g h(-1) or 90 g h(-1) or 100 g h(-1 
      13)C-glucose-(13)C-fructose [2:1] or placebo. CHO doses met, were marginally 
      lower, or above previously reported intestinal saturation for glucose-fructose 
      (90 g h(-1)). Indirect calorimetry and stable mass isotope [(13)C] techniques 
      were utilised to determine fuel use. RESULT: Time-trial performance was 86.5 to 
      93%, 'likely, probable' improved with 90 g h(-1) compared 80 and 100 g h(-1). 
      Exogenous CHO oxidation in the final hour was 9.8-10.0% higher with 100 g h(-1) 
      compared with 80 and 90 g h(-1) (ES = 0.64-0.70, 95% CI 9.6, 1.4 to 17.7 and 8.2, 
      2.1 to 18.6). However, increasing CHO dose (100 g h(-1)) increased muscle 
      glycogen use (101.6 +/- 16.6 g, ES = 0.60, 16.1, 0.9 to 31.4) and its relative 
      contribution to energy expenditure (5.6 +/- 8.4%, ES = 0.72, 5.6, 1.5 to 9.8 g) 
      compared with 90 g h(-1). Absolute and relative muscle glycogen oxidation between 
      80 and 90 g h(-1) were similar (ES = 0.23 and 0.38) though a small absolute 
      (85.4 +/- 29.3 g, 6.2, - 23.5 to 11.1) and relative (34.9 +/- 9.1 g, - 3.5, - 9.6 to 
      2.6) reduction was seen in 90 g h(-1) compared with 100 g h(-1). Liver glycogen 
      oxidation was not significantly different between conditions (ES < 0.42). Total 
      fat oxidation during the 3-h ride was similar in CHO conditions (ES < 0.28) but 
      suppressed compared with placebo (ES = 1.05-1.51). CONCLUSION: 'Overdosing' 
      intestinal transport for glucose-fructose appears to increase muscle glycogen 
      reliance and negatively impact subsequent TT performance.
FAU - King, Andy J
AU  - King AJ
AUID- ORCID: 0000-0002-3647-7025
AD  - Carnegie School of Sport, Fairfax Hall, Research Institute for Sport, Physical 
      Activity and Leisure, Leeds Beckett University, Leeds, LS6 3QT, UK. 
      a.k.king@leedsbeckett.ac.uk.
FAU - O'Hara, John P
AU  - O'Hara JP
AUID- ORCID: 0000-0003-1589-7984
AD  - Carnegie School of Sport, Fairfax Hall, Research Institute for Sport, Physical 
      Activity and Leisure, Leeds Beckett University, Leeds, LS6 3QT, UK.
FAU - Arjomandkhah, Nicola C
AU  - Arjomandkhah NC
AUID- ORCID: 0000-0001-9702-6749
AD  - Leeds Trinity University, Leeds, UK.
FAU - Rowe, Josh
AU  - Rowe J
AD  - Carnegie School of Sport, Fairfax Hall, Research Institute for Sport, Physical 
      Activity and Leisure, Leeds Beckett University, Leeds, LS6 3QT, UK.
FAU - Morrison, Douglas J
AU  - Morrison DJ
AD  - Scottish Universities Environmental Research Centre, Glasgow, UK.
FAU - Preston, Thomas
AU  - Preston T
AD  - Scottish Universities Environmental Research Centre, Glasgow, UK.
FAU - King, Roderick F G J
AU  - King RFGJ
AD  - Carnegie School of Sport, Fairfax Hall, Research Institute for Sport, Physical 
      Activity and Leisure, Leeds Beckett University, Leeds, LS6 3QT, UK.
LA  - eng
PT  - Journal Article
PT  - Randomized Controlled Trial
DEP - 20190306
PL  - Germany
TA  - Eur J Appl Physiol
JT  - European journal of applied physiology
JID - 100954790
RN  - 0 (Liver Glycogen)
RN  - 30237-26-4 (Fructose)
RN  - IY9XDZ35W2 (Glucose)
MH  - Administration, Oral
MH  - Adult
MH  - Double-Blind Method
MH  - *Exercise
MH  - Exercise Tolerance/*drug effects
MH  - Fructose/administration & dosage/*pharmacology
MH  - Glucose/administration & dosage/*pharmacology
MH  - Humans
MH  - Liver/drug effects/metabolism
MH  - Liver Glycogen/*metabolism
MH  - Male
MH  - Muscle, Skeletal/drug effects/*metabolism/physiology
MH  - Oxidation-Reduction
PMC - PMC6469629
OTO - NOTNLM
OT  - Carbohydrate ingestion
OT  - Exercise
OT  - Metabolism
OT  - Muscle glycogen
OT  - Stable isotope
COIS- The authors declare no conflict of interest.
EDAT- 2019/03/07 06:00
MHDA- 2019/08/01 06:00
PMCR- 2019/03/06
CRDT- 2019/03/07 06:00
PHST- 2018/07/26 00:00 [received]
PHST- 2019/02/15 00:00 [accepted]
PHST- 2019/03/07 06:00 [pubmed]
PHST- 2019/08/01 06:00 [medline]
PHST- 2019/03/07 06:00 [entrez]
PHST- 2019/03/06 00:00 [pmc-release]
AID - 10.1007/s00421-019-04106-9 [pii]
AID - 4106 [pii]
AID - 10.1007/s00421-019-04106-9 [doi]
PST - ppublish
SO  - Eur J Appl Physiol. 2019 May;119(5):1157-1169. doi: 10.1007/s00421-019-04106-9. 
      Epub 2019 Mar 6.