I agree with Shawn, it depends on what you’re eating. If you’re in a long endurance event (mara, tri) you’d better eat some readily available replenishment for glycogen reserves during the event! It also depends on how vigorous your workout will be.
When you eat, blood is drawn to the gut to help facilitate absorption and assimilation. When you do large muscle, rhythmic exercise like cycling, running, swimming, aerobics, obviously the blood flow increases to the exercising muscles to increase oxygen delivery. So, it depends a lot on intensity and duration.
Ask five different world class athletes and you’ll get five different answers to your question.