Effects of diet on muscle triglyceride and endurance
performance.
Starling, Raymond D., Todd A. Trappe, Allen C. Parcell, Chad. G. Kerr,
William J. Fink, and David L. Costill.
Human Performance Laboratory, Ball State University, Muncie, IN
47306
APStracts 3:0546A, 1996.
The purpose of this investigation was to examine the effects of diet
on muscle triglyceride and endurance performance. Seven endurance
-trained men completed a 120-min cycling bout at 65% of
O(V,sup10(.))O2max. Each subject then ingested an isocaloric, high
-carbohydrate (HI-CHO; 83% of energy) or high-fat (HI-FAT; 68% of
energy) diet for the ensuing 12 h. Following a 12 h overnight fast, a
1600 kJ self-paced cycling bout was completed. Muscle triglyceride
measured before (33.0 +/- 2.3 vs. 37.0 +/- 2.1 mmol x kg dw-1) and
after (30.9 +/- 2.4 vs. 32.8 +/- 1.6 mmol x kg dw-1) the 120-min
cycling bout was not different between the HI-CHO and HI-FAT trials,
respectively. Following the 24-h dietary/fasting period, muscle
triglyceride was significantly higher for the HI-FAT (44.7 +/- 2.4
mmol x kg dw-1) versus the HI-CHO (27.5 +/- 2.1 mmol x kg dw-1)
trial. Furthermore, self-paced cycling time was significantly greater
for the HI-FAT (139.3 +/- 7.1 min) compared to the HI-CHO (117.1 +/-
3.2 min) trial. These data demonstrate that there was not a
significant difference in muscle triglyceride concentration before
and after a prolonged, moderate-intensity cycling bout. Nevertheless,
a high-fat diet increased muscle triglyceride concentration and
reduced self-paced cycling performance 24 h after the exercise
compared to a high-carbohydrate diet.
Received 19 August 1996; accepted in final form 22 November 1996.
APS Manuscript Number A779-6.
Article publication pending Journal of Applied Physiology.
ISSN 1080-4757 Copyright 1996 The American Physiological Society.
Published in APStracts on 31 December 1996