PMID- 15320674
OWN - NLM
STAT- MEDLINE
DCOM- 20050111
LR  - 20161018
IS  - 1064-8011 (Print)
IS  - 1064-8011 (Linking)
VI  - 18
IP  - 3
DP  - 2004 Aug
TI  - Low vs. high glycemic index carbohydrate gel ingestion during simulated 64-km 
      cycling time trial performance.
PG  - 466-72
AB  - We examined the effect of low and high glycemic index (GI) carbohydrate (CHO) 
      feedings during a simulated 64-km cycling time trial (TT) in nine subjects ([mean 
      +/- SEM], age = 30 +/- 1 years; weight = 77.0 +/- 2.6 kg). Each rider completed 
      three randomized, double blind, counter-balanced, crossover rides, where riders 
      ingested 15 g of low GI (honey; GI = 35) and high GI (dextrose; GI = 100) CHO 
      every 16 km. Our results showed no differences between groups for the time to 
      complete the entire TT (honey = 128 minutes, 42 seconds +/- 3.6 minutes; dextrose 
      = 128 minutes, 18 seconds +/- 3.8 minutes; placebo = 131 minutes, 18 seconds +/- 
      3.9 minutes). However, an analysis of total time alone may not portray an 
      accurate picture of TT performance under CHO-supplemented conditions. For 
      example, when the CHO data were collapsed, the CHO condition (128 minutes, 30 
      seconds) proved faster than placebo condition (131 minutes, 18 seconds; p < 
      0.02). Furthermore, examining the percent differences and 95% confidence 
      intervals (CI) shows the two CHO conditions to be generally faster, as the 
      majority of the CI lies in the positive range: placebo vs. dextrose (2.36% [95% 
      CI; -0.69, 4.64]) and honey (1.98% [95% CI; -0.30, 5.02]). Dextrose vs. honey was 
      0.39% (95% CI; -3.39, 4.15). Within treatment analysis also showed that subjects 
      generated more watts (W) over the last 16 km vs. preceding segments for dextrose 
      (p < 0.002) and honey (p < 0.0004) treatments. When the final 16-km W was 
      expressed as a percentage of pretest maximal W, the dextrose treatment was 
      greater than placebo (p < 0.05). A strong trend was noted for the honey condition 
      (p < 0.06), despite no differences in heart rate (HR) or rate of perceived 
      exertion (RPE). Our results show a trend for improvement in time and wattage over 
      the last 16 km of a 64-km simulated TT regardless of glycemic index.
FAU - Earnest, Conrad P
AU  - Earnest CP
AD  - The Cooper Institute Center for Human Performance and Nutrition Research, Dallas, 
      Texas 75230, USA.
FAU - Lancaster, Stacy L
AU  - Lancaster SL
FAU - Rasmussen, Christopher J
AU  - Rasmussen CJ
FAU - Kerksick, Chad M
AU  - Kerksick CM
FAU - Lucia, Alejandro
AU  - Lucia A
FAU - Greenwood, Michael C
AU  - Greenwood MC
FAU - Almada, Anthony L
AU  - Almada AL
FAU - Cowan, Patty A
AU  - Cowan PA
FAU - Kreider, Richard B
AU  - Kreider RB
LA  - eng
PT  - Clinical Trial
PT  - Comparative Study
PT  - Journal Article
PT  - Randomized Controlled Trial
PT  - Research Support, U.S. Gov't, Non-P.H.S.
PL  - United States
TA  - J Strength Cond Res
JT  - Journal of strength and conditioning research
JID - 9415084
RN  - 0 (Blood Glucose)
RN  - 0 (Dietary Carbohydrates)
RN  - 0 (Gels)
RN  - IY9XDZ35W2 (Glucose)
SB  - IM
MH  - Adult
MH  - Bicycling/*physiology
MH  - Blood Glucose/analysis
MH  - Cross-Over Studies
MH  - Dietary Carbohydrates/*pharmacology
MH  - Double-Blind Method
MH  - Exercise/*physiology
MH  - Gels
MH  - Glucose/pharmacology
MH  - *Glycemic Index
MH  - Heart Rate/drug effects/physiology
MH  - Honey
MH  - Humans
MH  - Male
MH  - Physical Endurance/*drug effects/physiology
MH  - *Task Performance and Analysis
MH  - Time Factors
EDAT- 2004/08/24 05:00
MHDA- 2005/01/12 09:00
CRDT- 2004/08/24 05:00
PHST- 2004/08/24 05:00 [pubmed]
PHST- 2005/01/12 09:00 [medline]
PHST- 2004/08/24 05:00 [entrez]
AID - R-xxxxx [pii]
AID - 10.1519/R-xxxxx.1 [doi]
PST - ppublish
SO  - J Strength Cond Res. 2004 Aug;18(3):466-72. doi: 10.1519/R-xxxxx.1.