Exercising and being fit would definitely be an advantage. I did a little research and I guess a better way would be to have granola bars, nuts, fruit, maybe some energy bars low in sugar and water is a good way to keep going. Those are ideal cause you don't need to refrigerate. I was advised to try and eat every 2-3 hours, small snacks. It doesn't compensate for a full course meal though which is nice to kill some time during matches. I am going to try it for my next tournament and see how I feel.
I know a WPBA pro brings granola bars and nuts with her and eats them throughout the day. GuyI-NJ loves nuts.
Christian