TITLE

The Influence of Low Versus High Carbohydrate Diet on a 45-min Strenuous Cycling Exercise

AUTHOR(S)
Kavouras, Stavros A.; Troup, John P.; Berning, Jacqueline R.
PUB. DATE
February 2004
SOURCE
International Journal of Sport Nutrition & Exercise Metabolism;Feb2004, Vol. 14 Issue 1, p62
SOURCE TYPE
Academic Journal
DOC. TYPE
Article
ABSTRACT
To examine the effects of a 3-day high carbohydrate (H-CHO) and low carbohydrate (L-CHO) diet on 45 min of cycling exercise, 12 endurance-trained cyclists performed a 45-min cycling exercise at 82 ± 2% VO[sub2peak] following an overnight fast, after a 6-day diet and exercise control. The 7-day protocol was repeated under 2 randomly assigned dietary trials H-CHO and L-CHO. On days 1-3, subjects consumed a mixed diet for both trials and for days 4-6 consumed isocaloric diets that contained either 600g or 100g of carbohydrates, for the H-CHO and the L-CHO trials, respectively. Muscle biopsy samples, taken from the vastus lateralis prior to the beginning of the 45-min cycling test, indicated that muscle glycogen levels were significantly higher (p < .05) for the H-CHO trial (104.5 ± 9.4 mmol/kg wet wt) when compared to the L-CHO trial (72.2 ± 5.6 mmol/kg wet wt). Heart rate, ratings of perceived exertion, oxygen uptake, and respiratory quotient during exercise were not significantly different between the 2 trials. Serum glucose during exercise for the H-CHO trial significantly increased (p < .05) from 4.5 ± 0.1 mmol · L[sup-1] (pre) to 6.7 ± 0.6 mmol · L (post), while no changes were found for the L-CHO trial. In addition, postexercise serum glucose was significantly greater (p < .05) for the H-CHO trial when compared to the L-CHO trial (H-CHO, 6.7 ± 0.6 mmol · L[sup-1]; L-CHO, 5.2 ± 0.2 mmol · L[sup-1]. No significant changes were observed in serum free fatty acid, triglycerides, or insulin concentration in either trial. The findings suggest that L-CHO had no major effect on 45-min cycling exercise that was not observed with H-CHO when the total energy intake was adequate.
ACCESSION #
12399371

 

Share

Read the Article

Courtesy of THE LIBRARY OF VIRGINIA

Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics