One experiment may disprove the current understanding of blood sugars.
New York Times blogger Gretchen Reynolds answers that question in her recent posting.
She writes that 20 years ago, runners and other exercise enthusiasts were told not to eat an hour before they began their workouts. The rationale behind this precaution was that blood sugar levels would rise and then, presumably during the workout, those blood sugars would dip (called “rebound hypoglycemia”), resulting in decreased performance.
However, this may not be true.
New experiments are showing that this rebound hypoglycemia does occur, but that it doesn’t necessarily impede performance.
On study was performed on British cyclists who consumed sugary drinks before a challenging 20-minute ride. While some experienced blood sugar drops, this rebound hypoglycemia didn’t seem to stop them from completing their assigned workouts.
Reynolds points out that there is no question regarding the consumption of food. She says to eat if your workout was 45 minutes or longer. Any period less than that may result in consuming more calories than were burned during the workout.