Purpose: Atherosclerosis is initiated in childhood. Therefore, reducing postprandial triacylglycerol concentrations ([TAG]), even in young people, could potentially slow atherogenic progression. This study investigated whether continuous-exercise and intermittent-games activity would reduce postprandial [TAG] in adolescent boys.
Methods: Nineteen subjects were randomly assigned to either a continuous-exercise group (N = 10) or an intermittent-games group (N = 9) and underwent two 2-d trials. Trials were performed a minimum of 7 d apart in a randomized order, consisting of a rest trial and either a continuous-exercise or intermittent-games trial. In the rest trial, subjects took no exercise on day 1. On day 1 of the exercise trial, subjects completed four blocks (approximately 15 min each) of uphill treadmill walking or intermittent-games activity with 3 min of rest between each block. On day 2, subjects came to the laboratory after an overnight fast, and finger-prick blood samples were obtained in the fasted state. Subjects then consumed a test meal (1.25 g of fat, 1.07 g of carbohydrate, 0.20 g of protein, and 67 kJ·kg−1 body mass). Further blood samples were collected at 30 and 45 min and at 1, 3, 4, and 6 h postprandially.
Results: The total area under the plasma [TAG] versus time curve was lower on day 2 after exercise than the rest condition in both groups (Student's t-tests for correlated means: continuous-exercise group 14%, P = 0.050; intermittent-games group 26%, P = 0.002).
Conclusion: Both continuous-exercise and intermittent-games activity reduce [TAG] in healthy adolescent boys when performed the afternoon before ingesting a high-fat meal.
1Children's Health and Exercise Research Centre, School of Sport and Health Sciences, University of Exeter, UNITED KINGDOM; and 2Institute of Youth Sport, School of Sport and Exercise Sciences, Loughborough University, UNITED KINGDOM
Address for correspondence: Laura A. Barrett, Ph.D., Children's Health and Exercise Research Centre, School of Sport and Health Sciences, University of Exeter, Exeter, EX1 2LU, United Kingdom; E-mail: Laura.A.Barrett@exeter.ac.uk.
Submitted for publication March 2006.
Accepted for publication July 2006.