Is pre-exercise sugar harmful to performance?
A. More than 100 studies indicate consuming sugar within the hour pre-exercise does not hurt performance. The vast majority of runners can enjoy pre-exercise sweets for a quick fix. But some runners are, indeed, “sugar sensitive” and experience rebound hypoglycemia. They quickly learn— 1) to avoid sugar 15 to 45 minutes pre-exercise and instead consume it right before they exercise (the body will not have time to release the insulin that contributes to the “crash”) or 2) choose pre-run foods that do not produce a “sugar high” such as oatmeal or whole grain toast with a little peanut butter.
