The role of glycogen lowering exercise in the change of fat
oxidation in response to a high-fat diet.
Schrauwen, Patrick, Wouter D Van Marken Lichtenbelt, Wim H M Saris,
and Klaas R Westerterp.
Department of Human Biology, Maastricht University, Maastricht, The
Netherlands
APStracts 4:0135E, 1997.
One of the candidate factors for determining the increase of fat
oxidation after a switch from a reduced-fat diet to a high-fat diet
is the size of the glycogen storage. Therefore, we studied the effect
of low glycogen stores on fat oxidation after a switch from a
reduced-fat diet to a high-fat diet. Twelve healthy, non-obese males
and females (age: 22 +/- 1, BMI: 21.0 +/- 0.7, Wmax: 254 +/- 11 Watt)
consumed a reduced-fat diet (30/55/15% of energy from fat,
carbohydrate and protein respectively) three times at home for 3 days
(day 1-3). On two occasions subjects came to the laboratory on day 3
at 15.00 to perform an exhaustive glycogen lowering exercise (EX),
whereafter they went into the respiration chamber for a 36h stay. On
one occasion, subjects directly entered the respiration chamber at
18:00 for a 36h stay. In the respiration chamber they were given
either a high-fat diet (HF, 60/25/15% of energy from fat,
carbohydrate and protein respectively) or a reduced-fat diet (RF). In
both cases they were fed at energy balance. All diets were consumed
as breakfast, lunch, dinner and two or more snacks per day. On the HF
treatment, fat oxidation was below fat intake, indicating the slow
change of oxidation to intake on a high-fat diet. After the HF+EX
treatment, however, fat oxidation matched fat intake. In conclusion:
lean subjects are capable of rapidly adjusting fat oxidation to fat
intake when glycogen stores are lowered by exhaustive exercise.
Received 10 February 1997; accepted in final form 19 June 1997.
APS Manuscript Number E60-7.
Article publication pending Am. J. Physiol. (Endocrinol. Metab.).
ISSN 1080-4757 Copyright 1997 The American Physiological Society.
Published in APStracts on 10 July 1997