PMID- 19910651
OWN - NLM
STAT- MEDLINE
DCOM- 20100129
LR  - 20191111
IS  - 1526-484X (Print)
IS  - 1526-484X (Linking)
VI  - 19
IP  - 5
DP  - 2009 Oct
TI  - The effect of carbohydrate gels on gastrointestinal tolerance during a 16-km run.
PG  - 485-503
AB  - Two studies were conducted to investigate gastrointestinal (GI) tolerance of high 
      carbohydrate (CHO) intakes during intense running. The first study investigated 
      tolerance of a CHO gel delivering glucose plus fructose (GLU+FRC) at different 
      rates. The second study investigated tolerance of high intakes of glucose (GLU) 
      vs. GLU+FRC gel. Both studies used a randomized, 2-treatment, 2-period crossover 
      design: Endurance-trained men and women (Study 1: 26 men, 8 women; 37 +/- 11 yr; 
      73 +/- 9 kg; 1.76 +/- 0.07 m. Study 2: 34 men, 14 women; 35 +/- 10 yr; 70 +/- 9 
      kg; 1.75 +/- 0.09 m) completed two 16-km outdoor-runs. In Study 1 gels were 
      administered to provide 1.0 or 1.4 g CHO/min with ad libitum water intake every 
      3.2 km. In Study 2 GLU or GLU+FRC gels were given in a double-blind manner to 
      provide 1.4 g CHO/min. In both studies a postexercise questionnaire assessed 17 
      symptoms on a 10-point scale (from 0 to 9). For all treatments, GI complaints 
      were mainly scored at the low end of the scale. In Study 1 mean scores ranged 
      from 0.00 +/- 0.00 to 1.12 +/- 1.90, and in Study 2, from 0.00 +/- 0.0 to 1.27 
      +/- 1.78. GI symptoms were grouped into upper abdominal, lower abdominal, and 
      systemic problems. There were no significant treatment differences in these 
      categories in either study. In conclusion, despite high CHO gel intake, and 
      regardless of the blend (GLU vs. GLU+FRC), average scores for GI symptoms were at 
      the low end of the scale, indicating predominantly good tolerance during a 16-km 
      run. Nevertheless, some runners (~10-20%) experienced serious problems, and 
      individualized feeding strategies might be required.
FAU - Pfeiffer, Beate
AU  - Pfeiffer B
AD  - School of Sport and Exercise Sciences, University of Birmingham, Edgbaston, 
      Birmingham, B15 2TT, United Kingdom.
FAU - Cotterill, Alexandra
AU  - Cotterill A
FAU - Grathwohl, Dominik
AU  - Grathwohl D
FAU - Stellingwerff, Trent
AU  - Stellingwerff T
FAU - Jeukendrup, Asker E
AU  - Jeukendrup AE
LA  - eng
PT  - Journal Article
PT  - Randomized Controlled Trial
PT  - Research Support, Non-U.S. Gov't
PL  - United States
TA  - Int J Sport Nutr Exerc Metab
JT  - International journal of sport nutrition and exercise metabolism
JID - 100939812
RN  - 0 (Dietary Carbohydrates)
RN  - 0 (Gels)
RN  - 30237-26-4 (Fructose)
RN  - IY9XDZ35W2 (Glucose)
SB  - IM
MH  - Administration, Oral
MH  - Adult
MH  - Cross-Over Studies
MH  - Dietary Carbohydrates/*administration & dosage/adverse effects
MH  - Drinking
MH  - Female
MH  - Fructose/administration & dosage/adverse effects
MH  - Gastrointestinal Diseases/etiology
MH  - Gastrointestinal Tract/drug effects/metabolism/*physiology
MH  - *Gels
MH  - Glucose/administration & dosage/adverse effects
MH  - Humans
MH  - Male
MH  - Oxidation-Reduction
MH  - Oxygen Consumption
MH  - Physical Endurance/drug effects/*physiology
MH  - Running/*physiology
MH  - Task Performance and Analysis
EDAT- 2009/11/17 06:00
MHDA- 2010/01/30 06:00
CRDT- 2009/11/14 06:00
PHST- 2009/11/14 06:00 [entrez]
PHST- 2009/11/17 06:00 [pubmed]
PHST- 2010/01/30 06:00 [medline]
AID - 10.1123/ijsnem.19.5.485 [doi]
PST - ppublish
SO  - Int J Sport Nutr Exerc Metab. 2009 Oct;19(5):485-503. doi: 
      10.1123/ijsnem.19.5.485.