Dietary Composition Influences Short-term Endurance Training-Induced Adaptations of Substrate Partitioning during Exercise

Abstract

The purpose of the current study was to examine the influence of dietary composition on short-term endurance training-induced adaptations of substrate partitioning and time trial exercise performance. Eight untrained males cycled for 90 min at ∼54% aerobic capacity while being infused with [6,6 2H]glucose before and after two 10-d experimental phases separated by a 2-week washout period. Time trial performance was measured after the 90-min exercise trials before and after the 2nd experimental phase. During the first 10-d phase, subjects were randomly assigned to consume either a high carbohydrate or high fat diet while remaining inactive (CHO or FAT). During the second 10-d phase, subjects c..